History

The International Hydrofoil Society (IHS) Hydrofoil Correspondance Archives

					Hydrofoils: Military

Updated last August 20, 2006

History of Hydrofoils: People-Vessels-Operations

History of Hydrofoils: People-Vessels-Operations Top

Archived Messages

Count,MessageID,category,ShortTitle,Message,Date,UserName,MsgPswd,Phone,Email,ParentMsgId

“1”,”952795″,”4″,”What happened to the Flying DUKW||952795″,”
I am still in the process of restoring my Super Duck (product improved DUKW of WWII fame). While cruising the internet I saw a posting regarding what happened to the Flying Duck? this may be OBE, but here is some information. During the 31st Annual East Coast Military Vehicle Rally May 2004 at Ripken Stadium Aberdeen, MD; Mr. Tom Murray of Dover Delaware and I were looking at my Super Duck in the display area. Tom Murray is famous in military vehicle circles for his successful business of military vehicle salvage and restoration since WWII when his father started the business. In one passing remark Tom told me that he had bought the Flying Duck at an auction years ago. I had no interest at the time, but after seeing the posting thought someone might find the info useful. Tom Murray is now retired, his son John runs the business in Dover Delaware. The Flying Duck was probably scrapped years ago, but at least closes the chapter on what happened to it.
Regards
Tom…..
“,”2005-12-27″,”Tom Buonaugurio”,”nopswd”,” “,”surplusyes@comcast.net”,”4″

“2”,”945843″,”4″,”Obituary; Emmet D. Swank of Boeing||945843″,”
Emmett Swank, 84, passed away peacefully on December 7, 2005, in Everett. He was born in Unionville, Iowa, on October 22, 1921, to Claude and Clara Swank.
He was a graduate of Ford Kansas High School, class of 1939. He later joined the Army Air Corps and served proudly in Europe during World War II. He married June Wasson, in 1946, and they moved to the Everett area in 1956 to begin a career with the Boeing Company.

Emmett worked in the Boeing Hydrofoil Division, where he spent numerous years traveling throughout the world. Emmet spent many years as the production boss of hydrofoils and ended his career at Boeing as the Key West support group manager. He retired from Boeing in 1985.
Emmett is survived by his devoted wife of 59 years, June; sons, Gordon (Pamela) Swank, of Everett, and Dallas (Jeanne) Swank, of Monroe, Washingotn; grandsons, Emmett R. Swank, of Folsom, California, Logan D. Swank, of Marysville, Washington, and Robyn (Jay) Kibby, of Marysville; and brother, Wendell Swank, of Dodge City, Kansas.
He was preceded in his death by his son, David L. Swank; and three sisters.
At Emmett’s request, no services will be held.”,”2005-12-10″,”William white”,”nopswd”,” “,”whitewn@speakeasy.net”,”4″

“3”,”914592″,”4″,”Designer L E Baynes||914592″,”I found this answer to a question in Google and being a hydrofoil enthusiast I am intriqued.
Do any members of the Society know of the craft mentioned in the last sentence, please?
The following is the quote from the site:- http://answers.google.com/answers/threadview?id=70711
“Subject: Re: second world war
From: nigelweb-ga on 01 Aug 2004 17:37 PDT
=============== For general information:
L E Baynes AFRAeS… most famous for: inventor and held international
patents for first Swing Wing Aircraft (variable sweep).
Chronology (summary): 1919 patented first automatic variable pitch
airscrew, 1924-27 responsible for aerodynamic design of Short
‘Singapore’ Flying-Boat, 1929-30 Designs and manufactured first all
British glider to soar… Scud I. 1933-35 Scud II sailplanes; British
height record holder and international event winner. 1936 Designed and
built Scud III; first retractable and motored sailplane. 1937 Designed
and built first twin-engine pusher monoplane with wing-buried engines.
1939 Project designed ‘gas turbine system’ 100 passenger long-range
aircraft (for ref. see ‘Gas Turbines and Jet Propulsion for Aircraft’
by Geoffrey Smith 1942). 1938 Designed and patented first V/TOL swivel
turbine ‘Heliplane’ . 1939-45 Designed and built for M.O.S.
experimental tail-less flying wing (Baynes Bat) for tank carrying
project (initiated by Churchill) , Designed and implemented conversion
of Boston Bombers to search-light aircraft, submarine guided missiles
and other weapons and equipment for the RAF. 1946-48 Designed and
built for M.O.S. High-Lift Research Aircraft. 1949 Designed and
patented the first Variable-Sweep Fighter Aircraft for supersonic
flight. 1950-62 Designed and manufactured airliner equipment for major
aircraft companies and airlines. 1963-64 Designed and patented a
high-speed hydrofoil sea craft (made secret by the ministry).
“,”2005-10-15″,”T H Connell”,”med14pil”,” “,”t.connell@btopenworld.com”,”4″

“4”,”914591″,”4″,”Designer L E Baynes||914591″,”I found this answer to a question in Google and being a hydrofoil enthusiast I am intriqued.
Do any members of the Society know of the craft mentioned in the last sentence, please?
The following is the quote from the site:- http://answers.google.com/answers/threadview?id=70711
“Subject: Re: second world war
From: nigelweb-ga on 01 Aug 2004 17:37 PDT
=============== For general information:
L E Baynes AFRAeS… most famous for: inventor and held international
patents for first Swing Wing Aircraft (variable sweep).
Chronology (summary): 1919 patented first automatic variable pitch
airscrew, 1924-27 responsible for aerodynamic design of Short
‘Singapore’ Flying-Boat, 1929-30 Designs and manufactured first all
British glider to soar… Scud I. 1933-35 Scud II sailplanes; British
height record holder and international event winner. 1936 Designed and
built Scud III; first retractable and motored sailplane. 1937 Designed
and built first twin-engine pusher monoplane with wing-buried engines.
1939 Project designed ‘gas turbine system’ 100 passenger long-range
aircraft (for ref. see ‘Gas Turbines and Jet Propulsion for Aircraft’
by Geoffrey Smith 1942). 1938 Designed and patented first V/TOL swivel
turbine ‘Heliplane’ . 1939-45 Designed and built for M.O.S.
experimental tail-less flying wing (Baynes Bat) for tank carrying
project (initiated by Churchill) , Designed and implemented conversion
of Boston Bombers to search-light aircraft, submarine guided missiles
and other weapons and equipment for the RAF. 1946-48 Designed and
built for M.O.S. High-Lift Research Aircraft. 1949 Designed and
patented the first Variable-Sweep Fighter Aircraft for supersonic
flight. 1950-62 Designed and manufactured airliner equipment for major
aircraft companies and airlines. 1963-64 Designed and patented a
high-speed hydrofoil sea craft (made secret by the ministry).
“,”2005-10-15″,”T H Connell”,”nopswd”,” “,”t.connell@btopenworld.com”,”4″

“5”,”908710″,”4″,”Hovering Craft and Hydrofoil Index||908710″,”I have created and posted a list of articles for each of the past issues of Hovering Craft & Hydrofoil Magazine (predecessor to Fast Ferry International). Go to: www.exigent.info/HC&Hcontents.pdf

This is not a complete list, so I would very much appreciate additions from anybody who has copies of any issue or issues missing from the list!”,”2005-10-06″,”Barney C Black”,”poopdeck”,” “,” “,”4”

“6”,”884498″,”4″,”Re; Little Squirt = Pump Jet?||884498″,”Barney,

By the time of the 1968-69 issue (2nd issue) of Jane’s Surface Skimmer Systems, “Little Squirt” was being referred to as “Little Squirt” with no mention of an earlier name. They wrote: “Little Squirt was designed and built by Boeing in 1962 as a company sponsored water-jet research vehicle”.”,”2005-08-28″,”Martin Grimm”,”nopswd”,” “,”seaflite@alphalink.com.au”,”877875″

“7”,”877875″,”4″,”Little Squirt = Pump Jet?||877875″,”I just saw an article in the Jan 1963 edition of Hovering Craft and Hydrofoil about Boeing’s water-jet hydrofoil. The craft is named “Pump Jet” in the photo caption. Was this an early or maybe an “official” name for “Little Squirt”?”,”2005-08-16″,”Barney C Black”,”poopdeck”,” “,” “,”4”

“8”,”865794″,”4″,”Hovering Craft and Hydrofoil Mags on eBay||865794″,”I have put several lots of HC&H magazines up for auction on eBay. These are from Neil Lien’s collection, that he is cleaning up. Before auctioning them I am making an index of articles and keywords for the magazines I have… will put this up on the IHS site when I am done. There are some gaps in the magazines I have, so I will be asking people if they have any of the issues I have not seen if they would be willing to send information for the index. If you want to bid on some or all of these, go to eBay and search for hydrofoil. So far the magazines have been selling for about a dollar each plus postage.”,”2005-07-24″,”Barney C Black”,”poopdeck”,” “,” “,”0”

“9”,”856104″,”4″,”Re; AGEH-1 and PCH-1 Status||856104″,”I saw a set of plans (for a model in 1:25?)for sale on Ebay.com once.
Was to late for it.
It had a description in french.
I olny have the Popular Mechanics,but that’s to litle to make a
RC model of the Plainview…
Maybe someone out there know a bit more??

Gteetzz from Holland.
“,”2005-07-05″,”Mark van Rijzen”,”nopswd”,” “,”dutchhydrofoils@wanadoo.nl”,”0″

“10”,”855605″,”4″,”Re; AGEH-1 and PCH-1 Status||855605″,”added photo (last of 4)”,”2005-07-04″,”Tom Jensen”,”nopswd”,” “,”c180tom@eskimo.com”,”0″

“11”,”855603″,”4″,”Re; AGEH-1 and PCH-1 Status||855603″,”added photo (3 of 4)”,”2005-07-04″,”Tom Jensen”,”nopswd”,” “,”c180tom@eskimo.com”,”0″

“12”,”855601″,”4″,”Re; AGEH-1 and PCH-1 Status||855601″,”added photos (4 total)”,”2005-07-04″,”Tom Jensen”,”nopswd”,” “,”c180tom@eskimo.com”,”0″

“13”,”855597″,”4″,”AGEH-1 and PCH-1 Status||855597″,”I took the enclosed pictures of poor ol’ Plainview grounded in Hungry Harbor on March 25, 2005 when visiting the Astoria and Long Beach area. There is a rough “Gyppo” salvage operation underway, probably reflecting the price of aluminum. Seeing the innards exposed was sad and almost disrespectful, but it brought back many memories. (e.g., the hullborne line shaft couplings visible in .1.1 reminded me of hanging over the railing in that compartment late at night in north of Haro Straights, replacing the shear pins in a coupling. The engineering crew made suitable temporary pins from a bolt and installing it was sure proof of my sea legs, with fumes and sea conditions causing lots of rolling motion.) I have some almost “artsy” Plainview slides from the early 70’s, including one of the supercavitating propellers against an evening sky. If you think folks would be interested, I’ll dig them out and scan a few. I also tried to run down the location of PCH-1. It had apparently been moved from the private dock east of the Maritime museum in Astoria to Tongue Point. The area was closed to the public so I couldn’t investigate further. It was rumored to have been scrapped. Sincerely, Tom Jensen Boeing engineering support of Hystu, 1971-1975 “,”2005-07-04″,”Tom Jensen”,”nopswd”,” “,”c180tom@eskimo.com”,”0″

“14”,”824682″,”4″,”Re; Hydrofoil Archieves||824682″,”Search our web site under High Pockets (Note Two Words)

Typical finds on our site at: //archive.foils.org/baker.htm#hp

I doubt any real technical reports have survived within the Navy from that far back. At least I do not remember any from the Advanced Ship Data bank of reports at Caderock DTNSRDC.

Bill White”,”2005-05-06″,”white”,”nopswd”,” “,”whitewn@speakeasy.net”,”0″

“15”,”824464″,”4″,”Hydrofoil Archieves||824464″,”Can anyone give me a reference to obtain “HIGHPOCKETS” technical reports?

Also the same for “SEALEGS”

Gerry Levine, GALUS MARINE LLC
e-mail levinega@galusmarine.com

561-628-5940″,”2005-05-06″,”Gerry Levine”,”nopswd”,” “,”gerrymega@adelphia.net”,”0″

“16”,”795121″,”4″,”Longest Voyage||795121″,”I have a history question: What is the longest voyage made by a full-flying hydrofoil? That is, a boat capable of lifting the whole hull out of the water, as opposed to a boat that is foil-stabilized and retains some buoyant support at all times.

Has any full-flying hydrofoil ever crossed an ocean? Circumnavigated?”,”2005-03-12″,”Tom Speer”,”nopswd”,” “,”me@tspeer.com”,”0″

“17”,”790207″,”4″,”Re: Plainview Patch / Badge Origin||790207″,”Referring to the picture provided in the original message by Barney Black, the top left patch is the original logo designed by POIC Lt. Hugh Burkons. Plaques were also cast with this logo. Some time later, the top right patch took over. Designer is unknown to me. Plaques were also cast with this logo. The bottom patch is the military hydrofoil generic patch. Patches were made for all the military hydrofoils with this logo with their respective names. “,”2005-03-03″,”S. Arima”,”nopswd”,” “,”SA_IHS_1980@verizon.net”,”0″

“18”,”790045″,”4″,”Plainview Patch / Badge Origin||790045″,”Can anyone tell me anything about the origin and authenticity of the patches in the photo? Which organization issued them and when? Why the three different versions? Are there any other Plainview patches issued that are not represented in the photo? Thanks!”,”2005-03-03″,”Barney C Black”,”nopswd”,” “,”bcblack@erols.com”,”0″

“19”,”787382″,”4″,”In Memoriam: Harlowe Longfelder||787382″,”Sumi Arima submitted the following link to the obituary for Harlowe Longfelder printed in the Seattle Post Intelligencer. He was a leader in Boeing’s space and missile programs, as well as the hydrofoil boat program. For a time, he was Al Rand’s boss on the HYSTU support contract.

http://www.legacy.com/Link.asp?Id=LS03207915X

“,”2005-02-25″,”Barney C Black”,”poopdeck”,” “,”bcblack@erols.com”,”0″

“20”,”743860″,”4″,”JETFOIL model pics. (nm) ||743860″,”No Message”,”2004-11-26″,”yoichi takahashi “,”nopswd”,” “,”skyex@triton.ocn.ne.jp”,”0″

“21”,”743858″,”4″,” Wonderful Boeing jetfoil (nm) ||743858″,”No Message”,”2004-11-26″,”yoichi takahashi “,”nopswd”,” “,”skyex@triton.ocn.ne.jp”,”0″

“22”,”743857″,”4″,”JETFOIL model pics. (nm) ||743857″,”No Message”,”2004-11-26″,”yoichi takahashi “,”nopswd”,” “,”skyex@triton.ocn.ne.jp”,”0″

“23”,”743856″,”4″,”JETFOIL model pics. (nm) ||743856″,”No Message”,”2004-11-26″,”yoichi takahashi “,”nopswd”,” “,”skyex@triton.ocn.ne.jp”,”0″

“24”,”743855″,”4″,” Wonderful Boeing jetfoil ||743855″,”Hello. Clark Dodge san
Since the mail like the point was imperfect, it re-contributes. I am a Japanese radio control ship maniac. Your contribution report was read. I very like the Boeing jetfoil. The photograph of a radio control jetfoil which I manufactured to BBS in March, this year was carried. In order to make this jetfoil, I went to ride on the jetfoil put into service to Kansai Airport in Japan, and experienced the wonderful degree of comfort. You who participated in the program which builds such a wonderful ship are wonderful. The picture of the radio control model of the Boeing jetfoil which I manufactured is sent here again. Above”,”2004-11-26″,”yoichi takahashi “,”nopswd”,” “,”skyex@triton.ocn.ne.jp”,”0″

“25”,”743844″,”4″,”A wonderful jetfoil program||743844″,”control ship maniac, I very like the Boeing jetfoil. My model radio control jetfoil was contributed also to this BBS in March, this year. And I went to take purposely the ship of thing of the jetfoil put into service to access of Kansai Airport in Japan, in order to make the radio control model of this jetfoil, and I have experienced the wonderful degree of comfort. It is very wonderful that you came considering development of the jetfoil of the wonderful degree of comfort as work. Here, since the radio control jetfoil which I made is contributed once again here, please see. Above”,”2004-11-26″,”yoichi takahashi “,”nopswd”,” “,”skyex@triton.ocn.ne.jp”,”0″

“26”,”743420″,”4″,”Re: Boeing Jetfoil Program||743420″,”Clark, there is a group of retired Boeing engineers in the Seattle area that are veterans of Boeing’s various hydrofoil programs and that meet for lunch occasionally and informally to keep in touch and remember old times. I believe I have email addresses for a couple of them that I know from the Navy PHM program, so I will forward your posting to them.”,”2004-11-24″,”Barney C Black”,”poopdeck”,” “,”barney@alum.mit.edu”,”0″

“27”,”737676″,”4″,”Boeing Jetfoil Program||737676″,”I just thought I would send a note about the Boeing Jetfoil, and the
documents you have on IHS.

I am a SNAME member of the Pacific Northwest Section, (#17706) and the
senior Staff Chief Engineer for Washington State Department of
Transportation Marine Division. One of my fun times was a part of the
Boeing Jetfoil test program in Seattle. These vessel were absolutely a
dream to work and ride. It is a shame that as much work was not put into
them to make them work as the negative attacks. Compared to many vessels
today they were a good melt of airplane and vessel. I have many hours of
riding and night maintenance to remember. They were a blast.

Now after 38 years and enjoying my present assignment as Staff Chief
Engineer of the Jumbo Mark II, MV Wenatchee, I am retiring to pursue my
consulting business.

Clark Dodge, President
CED Consulting LLC
225 SW 171st. Street
Seattle, WA. 98166
(206) 244-9849
Phone: 206-244-9849
Fax: 206-988-3769
Clark@burien.net
“,”2004-11-14″,”Clark Dodge”,”theboard”,” “,”Clark@burien.net”,”0″

“28”,”705827″,”4″,”Re: Current Status of PHMs||705827″,”Thanks for that update, Dan. I will make sure the IHS NL editor sees your status report… he may well want to include it in the next newsletter… if so, he may ask you for a couple of photos to illustrate the news.”,”2004-09-08″,”Barney C Black”,”poopdeck”,” “,”bcblack@erols.com”,”0″

“29”,”702077″,”4″,”Current Status of PHMs||702077″,”I recently went on vacation in North Carolina. Prior to me leaving I contacted Eliot James (owner PHM-5) and he gave me contact information for Jim Lovlace the person who had purchased the other 4 remaining foils(PHM-2,3,5&6).

Two of the ships have been scrapped (PHM-2 and an unknown)

I got a personal tour of PHM-6 which has been re-outfitted with (3) 16V92 Detroit Diesels for Propulsion. The center gas turbine propulsor was replaced by one of the diesel driven ones from a scrapped PHM. The sides our now white and mirror smooth, gone are the days of print-thru thanks to high end marine bondo. There is an observation window set in the front bow area and a pair of glass bottom windows in the aft just forward of the hullborne waterjet intakes..The discussion of the day was trying to decide on a 8 or 10 person hot tub where the turbine exhaust once was.

The remaining untouched phm I walked around on taking many pictures and some digital video. My guess is that it was the Taurus but may have been the Aquila. They started cutting it up for scrap but the hydraulics on the front actuator leaked and the coast guard had shut down the scrapping.

David Jennings the owner of the Gemini (PHM-6) Purchased that remaining mystery PHM on the day I was there saving it from a Norfolk scrapyard. He stated that he is unsure of how extreme of a makeover the remaining PHM will have.

I guess the ships contain some very interesting metallurgy according to Jim Lovelace. He said that most parts are a very corrosion resistant aluminum. He hardly noticed any corrosion on the Phm’s as they were cut up. Also some water was in the bilge of the PHM I toured but hardly noticed any corrosion.

The final score:

PHM-1 (gone, cut up in Charleston SC)
PHM-2 (gone, cut up in Wilmington NC)
PHM-3 & 4 (one gone one exists)
PHM-5 (sitting safely in the Missouri River being restored)
PHM-6 (extreme makeover is an understatement)

Dan Schmidt
“,”2004-08-30″,”Dan Schmidt”,”theboard”,” “,”gse2schmidt@ameritech.net”,”0″

“30”,”697280″,”4″,”Re; Re; AGEH-1 Plainview Plans||697280″,”Hi Mark, the record of the ebay auction will still be on the ebay website for a few weeks, so it would be possible to contact the winning bidder to see if he or she would be willing to make a copy and give or sell it. If you do not remember the item number, it is possible to search the ended auctions to find it again. – BArney”,”2004-08-20″,”Barney C Black”,”poopdeck”,” “,”bcblack@erols.com”,”0″

“31”,”694059″,”4″,”Re; AGEH-1 Plainview Plans||694059″,”Hello, I saw one go up for sale on ebay.com,but I was to late to buy it..The decripion was in french.”,”2004-08-13″,”Capt Mark van Rijzen”,”nopswd”,” “,”dutchhydrofoils@wanadoo.nl”,”0″

“32”,”692416″,”4″,”Re; AGEH-1 Plainview Plans||692416″,”James,
Early issues of Jane’s Surface Skimmers (from late 60’s) contained small scale three view drawings of the Plainview. They would hardly be sufficient to build a good scale model from however. The other suggestion therefore is for you to browse through 60’s vintage issues of “Hovering Craft and Hydrofoil” journal as that may contain a better arrangement drawing. This journal may be held at larger libraries or those of universities. “,”2004-08-10″,”Martin Grimm”,”nopswd”,” “,”seaflite@alphalink.com.au”,”0″

Speedboat / Hydrofoil Racing History

Speedboat Racing History Question

sharonandmike@mindspring.com

webmaster@foils.org

seaflite@alphalink.com.au

[Date/Time=03-23-2002 – 1:01 AM]

Name:webmaster@foils.org [Msgid=237131]
Archive; PLAINVIEW (AGEH-1) Updates

ViewThread
Click below to Open.

https://archive.foils.org/plainvw.htm
[Date/Time=03-24-2002 – 1:40 AM]

Name:webmaster@foils.org [Msgid=237497]
Archive; HIGH POINT (PCH-1)
Click below to Open.

https://archive.foils.org/highpt.htm
[Date/Time=03-24-2002 – 1:43 AM]

Name:webmaster@foils.org [Msgid=237498]
Archive; FLAGSTAFF (PGH-1)
Click below to Open.

https://archive.foils.org/flagstaff.htm
[Date/Time=03-24-2002 – 1:45 AM] Name:webmaster@foils.org [Msgid=237500]
Archive; Other Historic Hydrofoils
click below to Open.

https://archive.foils.org/pioneers.htm#letters
[Date/Time=03-24-2002 – 11:47 AM]

Name:webmaster@foils.org [Msgid=237606]
Archive; History of IHS
Click below to Open

https://archive.foils.org/ihs25his.pdf
[Date/Time=03-24-2002 – 3:19 PM]

Name:webmaster@foils.org [Msgid=237688]
Archive; PLAINVIEW (AGEH-1) Updates

https://archive.foils.org/plainvw.htm

[Date/Time=05-12-2002 – 7:34 AM]

Name:Bob Cline clinewlt@pacifier.com, [Msgid=258421]
Why Aren`t There More Hydrofoils?

ViewThread

[Date/Time=05-31-2002 – 9:50 PM]

Name:Gerald Levine GERRYMEGA@aol.com, [Msgid=266151]
Why Aren`t There More Hydrofoils?

https://archive.foils.org/morefoil.htm

https://archive.foils.org/knots.htm

https://foils.org/wp-content/uploads/2018/09/phmhist.pdf

https://archive.foils.org/log.htm

https://archive.foils.org/theboard.htm

- - - 1. Hydrofoil passenger vessels are common in Russia, for example, and if there are fewer today than yesterday, this may be more a reflection of the Russian economy than of a hydrofoil failure
      2. PHMs were a failure in that only the USA followed through to buy any, but they were a success in counternarcotics and FleetEx activities conducted out of Key West. Yes they were decommissioned with many years of service life remaining. The main reason cited was operating and maintenance costs; however keep in mind that these ships had the highest OPTEMPO of any class in the Navy and were kept ready to scramble on short notice. Their mission is now being accomplished by much larger blue water warships with larger crews and costly weapons suites that have little utility for drug busting
      3. The hydrofoils that Helmut Kock assembled on Lake Titicaca in Peru are still carrying tourists today
  So it is more accurate to say that hydrofoils have successfully found their niches here and there in the past. Likely they will continue to do so. There is still quite a bit of interest around the world in hydrofoils, as evidenced every day by the participation in IHS.

[Date/Time=06-01-2002 – 6:21 AM]

Name:Barney C. Black webmaster@foils.org, [Msgid=266225]
Why Aren`t There More Hydrofoils?

[Date/Time=06-08-2002 – 7:34 AM]

Name:Jim King dominionmaritime@aol.com, [Msgid=269043]
PHM 1 PEGASUS Plankowner

[Date/Time=06-10-2002 – 7:06 AM]

Name:Carl A. Allison guzzi007@postoffice.pacbell.net, [Msgid=269632]
Archive; PLAINVIEW (AGEH-1) Updates

[Date/Time=06-10-2002 – 3:23 PM]

Name:Quinton G. Steckler qsteckler@tuthill.com, [Msgid=269818]
Archive; PLAINVIEW (AGEH-1) Updates

[Date/Time=06-19-2002 – 5:35 PM]

Name:S. Arima arimas1@juno.com, [Msgid=273467]
Archive; PLAINVIEW (AGEH-1) Updates

[Date/Time=06-20-2002 – 12:58 PM]

Name:S. Arima arimas1@juno.com, [Msgid=273755]
HIGH POINT Veteran

[Date/Time=06-22-2002 – 3:23 PM]

Name:Marty catheyj54@aol.com, [Msgid=274424]
Hydrodynamic Test System HTS

ViewThread

[Date/Time=06-29-2002 – 9:27 PM]

Name:Michael Prophet sharonandmike@mindspring.com, [Msgid=276943]
Hydrodynamic Test System HTS

[Date/Time=06-29-2002 – 9:30 PM]

Name:Sumi Arima arimas1@juno.com, [Msgid=276944]
Hydrodynamic Test System HTS

[Date/Time=06-29-2002 – 9:33 PM]

Name:John Meyer jmeyer@erols.com, [Msgid=276945]
Hydrodynamic Test System HTS

Hovering Craft and Hydrofoil

AQUA-JET

[Date/Time=06-30-2002 – 8:04 AM]

Name:Martin Grimm seaflite@alphalink.com.au, [Msgid=277035]
Hydrodynamic Test System HTS

- - 1. Three point hydroplane
    2. 14,000 lb gross weight
    3. Pratt and Whitney J-48 turbojet engine of 7,200 lb thrust
    4. Max speed 145 knots without model hydrofoil, 80 knots with model hydrofoil

[Date/Time=06-30-2002 – 8:10 AM]

Name:Martin Grimm seaflite@alphalink.com.au, [Msgid=277036]
Larson VOLERO With Foils

[Date/Time=06-30-2002 – 8:15 AM]

Name:Ed Anderson larsonboats@larsonboats.com, [Msgid=277037]
spargi/Curl Curl

ViewThread

nic_patrick@hotmail.com
[Date/Time=07-01-2002 – 7:36 AM]

Name:nick patrick nic_patrick@hotmail.com, [Msgid=277342]
spargi/Curl Curl

https://www.usticalines.it/flotta.htm

[Date/Time=07-03-2002 – 4:11 AM]

Name:Martin Grimm seaflite@alphalink.com.au, [Msgid=278259]
Museums for Hydrofoils?

ViewThread

[Date/Time=07-04-2002 – 5:52 PM]

Name:C. Schramm c_schramm@t-online.de, [Msgid=278839]
Museums for Hydrofoils?

[Date/Time=07-04-2002 – 5:55 PM]

Name:Barney Black webmaster@foils.org, [Msgid=278840]
Museums for Hydrofoils?

[Date/Time=07-04-2002 – 6:00 PM]

Name:Martin Grimm seaflite@alphalink.com.au, [Msgid=278841]
Museums for Hydrofoils?

[Date/Time=07-04-2002 – 6:05 PM]

Name:C. Schramm c_schramm@t-online.de, [Msgid=278843]
Museums for Hydrofoils?

https://www.hover.globalinternet.co.uk/

https://www.helicoptermuseum.org/

https://www.helicoptermuseum.co.uk/

[Date/Time=07-04-2002 – 6:08 PM]

Name:Martin Grimm seaflite@alphalink.com.au, [Msgid=278845]
Museums for Hydrofoils?

[Date/Time=07-04-2002 – 6:18 PM]

Name:C. Schramm c_schramm@t-online.de, [Msgid=278846]
Happy Golden Anniversary Supramar

[Date/Time=07-05-2002 – 9:17 AM]

Name:Martin Grimm seaflite@alphalink.com.au, [Msgid=278959]
New Hydrofoil Video – Discovery

https://www.hydrofoil.ca/

lucy@thesea.ca

[Date/Time=07-22-2002 – 11:01 AM]

Name:Lou Duggan lou@thesea.ca, [Msgid=285147]
GORDON BAKER STORY

ViewThread

[Date/Time=08-02-2002 – 5:46 PM]

Name:Charles E. Thompson cethomstaug@aol.com, [Msgid=289706]
Attached File “The Gordon Baker Story with photospart1~doc.zip” – size 353792 Click Here To Download
Gordon Baker Story

ViewThread

[Date/Time=08-02-2002 – 9:35 PM]

Name:Charles Thompson cethomstaug@aol.com, [Msgid=289772]
Gordon Baker Story

https://archive.foils.org/baker.htm

MONITOR

https://archive.foils.org/monitor.htm

MONITOR

https://home-1.tiscali.nl/~hbsmits/monitor1.htm

MONITOR

nlien@inwave.com

[Date/Time=08-03-2002 – 1:40 PM]

Name:Barney C. Black webmaster@foils.org, [Msgid=289999]
Hydrodynamic Test Systems (HTS)

[Date/Time=08-10-2002 – 12:57 PM]

Name:Bruce Bryant bryant@silverlink.net, [Msgid=293978]
GORDON BAKER STORY

[Date/Time=08-18-2002 – 12:31 PM]

Name:Neil Lien nlien@inwave.com, [Msgid=297576]
GORDON BAKER STORY

[Date/Time=08-18-2002 – 10:09 PM]

Name:Bill White whitewn@speakeasy.net, [Msgid=297754]
Historical Market for Hydrofoil Boats

ViewThread

[Date/Time=10-15-2002 – 7:21 PM]

Name:Tomas J?rnmark Tomas.Jarnmark@electrum.se, [Msgid=324190]
Bras D`Or Propulsion Question

ViewThread

[Date/Time=10-20-2002 – 8:06 AM]

Name:J. P. Carole jpcarole@aol.com, [Msgid=326108]
Bras D`Or Propulsion Question

The Flying 400: Canada’s Hydrofoil Project

[Date/Time=10-20-2002 – 8:21 AM]

Name:Barney C. Black webmaster@foils.org, [Msgid=326110]
Historical Market for Hydrofoil Boats

[Date/Time=10-23-2002 – 10:55 PM]

Name:Matt Kirk matric39@gte.net, [Msgid=327988]
Historical Market for Hydrofoil Boats

https://www.solomontechnologies.com/home.htm

[Date/Time=11-04-2002 – 7:56 PM]

Name:Bill White whitewn@speakeasy.net, [Msgid=333478]
Historical Market for Hydrofoil Boats

[Date/Time=11-05-2002 – 12:13 AM]

Name:Harry Larsen hlarsen0@gte.net, [Msgid=333585]
Where is the Disco Volante

ViewThread

[Date/Time=11-22-2002 – 4:27 AM]

Name:Mark A. Burris BurrisLM@aol.com, [Msgid=341785]
Where is the Disco Volante

https://foils.org

[Date/Time=11-23-2002 – 6:21 PM]

Name:Bill White whitewn@flash.net, [Msgid=342522]
[i]USS ARIES[/i] Memorial NL

USS ARIES

https://www.ussaries.org

USS FOREST SHERMAN

[Date/Time=11-27-2002 – 4:17 AM]

Name:Eliot James esjames@cvalley.net, [Msgid=344092]
Sea Wing history?

ViewThread

[Date/Time=12-11-2002 – 5:19 AM]

Name:Eje Flodstrom eje_flodstrom@yahoo.com, [Msgid=349689]
Sea Wing history?

[Date/Time=12-12-2002 – 5:24 AM]

Name:Martin Grimm seaflite@alphalink.com.au, [Msgid=350180]
Sea Wing history?

[Date/Time=12-12-2002 – 3:31 PM]

Name:Eje Flodstrom eje_flodstrom@yahoo.com, [Msgid=350439]
Sea Wing history?

[Date/Time=12-15-2002 – 1:25 AM]

Name:Martin Grimm seaflite@alphalink.com.au, [Msgid=351469]
3 inch Chord

[Date/Time=12-19-2002 – 9:25 PM]

Name:Matt Kirk matric39@gte.net, [Msgid=353684]
Jetfoils Relationship to Chinese PS30

ViewThread

[Date/Time=01-27-2003 – 8:17 PM]

Name:Neil Howe Neil@beurteaux.com, [Msgid=368023]
Re; Jetfoils Relationship to Chinese PS30

[Date/Time=01-28-2003 – 9:06 PM]

Name:Harry Larsen hlarsen0@gte.net, [Msgid=368659]
Re; Jetfoils Relationship to Chinese PS30

[Date/Time=02-02-2003 – 11:51 AM]

Name:Martin Grimm seaflite@alphalink.com.au, [Msgid=371013]
Re; Jetfoils Relationship to Chinese PS30

[Date/Time=02-02-2003 – 11:54 AM]

Name:Mark Bebar markbebar@juno.com, [Msgid=371016]
Re; Jetfoils Relationship to Chinese PS30

Fast Ferry International

Classic Fast Ferries

https://archive.foils.org/linksout.htm

Jane’s High Speed Marine Craft

stdong@online.sh.cn

[Date/Time=02-02-2003 – 11:59 AM]

Name:Barney C Black webmaster@foils.org, [Msgid=371019]
Re; Jetfoils Relationship to Chinese PS30

https://www.sentex.net/~sxing/ps30_high_speed_passenger_ferry.htm

[Date/Time=02-02-2003 – 1:23 PM]

Name:Barry Steele barry_steele@yahoo.com, [Msgid=371058]
Re; Jetfoils vis a vis Chinese PS30

[Date/Time=02-07-2003 – 8:25 AM]

Name:Phil Janosik janosik1@tx3.com, [Msgid=373847]
Niel Lein, Monitor, and Baker Mfg Co,

[Date/Time=02-25-2003 – 9:50 AM]

Name:Dave Carlson afn18791@afn.org, [Msgid=384530]
LITTLE SQUIRT Gas Turbine Engine

https://archive.foils.org/engine.htm

LITTLE SQUIRT

[Date/Time=02-26-2003 – 7:40 PM]

Name:Tim Pratt timp%@compatiblecomputers.com, [Msgid=385543]
VolgeVingen Restoration

[Date/Time=02-28-2003 – 7:05 PM]

Name:Jan Wennerstrom jan.wennerstrom@bredband.net, [Msgid=386807]
In Memory of Ray Wright

[Date/Time=03-07-2003 – 5:02 AM]

Name:Charlie Pieroth SoundTM@ix.netcom.com, [Msgid=390899]
A Hydrofoil Museum is Proposed

ViewThread

https://www.hover.globalinternet.co.uk/

https://www.helicoptermuseum.org/

https://www.helicoptermuseum.co.uk/
[Date/Time=03-24-2003 – 8:03 PM]

Name:Martin Grimm seaflite@alphalink.com.au, [Msgid=402303]
Re; A Hydrofoil Museum is Proposed

[Date/Time=03-24-2003 – 8:10 PM]

Name:C. Schramm c_schramm@t-online.de, [Msgid=402309]
Re; A Hydrofoil Museum is Proposed

[Date/Time=03-24-2003 – 8:12 PM]

Name:Mark Bebar markbebar@juno.com, [Msgid=402310]
Wendels Schnellschiff

[Date/Time=03-24-2003 – 8:37 PM]

Name:C. Schramm c_schramm@t-online.de, [Msgid=402327]
hydrofoil museum

ViewThread

[Date/Time=03-25-2003 – 11:44 AM]

Name:Ken Spaulding, IHS Secretary kboyd@erols.com, [Msgid=402670]
Re; hydrofoil museum

www.ussaries.org

[Date/Time=03-25-2003 – 6:26 PM]

Name:Eliot James esjames@cvalley.net, [Msgid=402944]
Thoughts on a Hydrofoil Museum

ViewThread

[Date/Time=03-26-2003 – 8:59 AM]

Name:Robert Miller cbbi@aol.com, [Msgid=403346]
Re; Thoughts on a Hydrofoil Museum

ViewThread

[Date/Time=03-26-2003 – 10:03 AM]

Name:Eliot James esjames@cvalley.net, [Msgid=403376]
re; Museum

https://corpsdriver.home.attbi.com/hydrofoils.htm
[Date/Time=03-28-2003 – 12:23 AM]

Name:J Hahn corpsdriver@attbi.com, [Msgid=404711]
Hydrofoil Size

ViewThread

[Date/Time=04-12-2003 – 3:45 PM]

Name:Kevin Tse kevin@softrepublic.com, [Msgid=415658]
Large Hydrofoil Passenger Liners

https://archive.foils.org/popmags.htm

Technical World Magazine,

Popular Science

[Date/Time=04-13-2003 – 7:05 AM]

Name:Barney C Black webmaster@foils.org, [Msgid=415992]
Re; Hydrofoil Size

[Date/Time=04-15-2003 – 12:16 AM]

Name:Bill White bbs@foils.org, [Msgid=417239]
Re; Hydrofoil Size

https://www.sun.ac.za/kie/unistel/technologies/applics.htm

[Date/Time=04-20-2003 – 9:54 PM]

Name:Michael W. Preis mpreis@liu.edu, [Msgid=421047]
Re; Re; Hydrofoil Size

[Date/Time=04-22-2003 – 3:35 AM]

Name:Gunther Migeotte gunther@cae.co.za, [Msgid=421765]
Re; Hydrofoil Size

[Date/Time=04-24-2003 – 9:23 AM]

Name:Martin Grimm seaflite@alphalink.com.au, [Msgid=423501]
Re; Re; Hydrofoil Size

[Date/Time=04-24-2003 – 9:43 AM]

Name:Gunther Migeotte gunther@cae.co.za, [Msgid=423511]
Re; Re; Re; Hydrofoil Size

HTTPs://www.islandengineering.com

[Date/Time=04-24-2003 – 10:22 AM]

Name:Rick Loheed RLoheed@islandengineering.com, [Msgid=423533]
Re; Re; Re; Re; Hydrofoil Size

ViewThread

[Date/Time=04-24-2003 – 11:26 AM]

Name:Gunther Migeotte gunther@cae.co.za, [Msgid=423576]
re;

HTTPs://www.islandengineering.com

[Date/Time=04-24-2003 – 12:01 PM]

Name:Rick Loheed RLoheed@islandengineering.com, [Msgid=423588]
Re; Hydrofoil Size

[Date/Time=04-28-2003 – 10:25 AM]

Name:Martin Grimm seaflite@alphalink.com.au, [Msgid=426363]
Re; Re; Hydrofoil Size

ViewThread

[Date/Time=04-30-2003 – 3:19 AM]

Name:Gunther Migeotte gunther@cae.co.za, [Msgid=427677]
Re; Re; Re; Hydrofoil Size

[Date/Time=05-06-2003 – 8:32 AM]

Name:Martin Grimm seaflite@alphalink.com.au, [Msgid=431041]
Re; Re; Re; Hydrofoil Size

ViewThread

[Date/Time=05-06-2003 – 8:34 AM]

Name:Martin Grimm seaflite@alphalink.com.au, [Msgid=431042]
Re; Re; Re; Re; Hydrofoil Size

[Date/Time=05-06-2003 – 11:57 AM]

Name:Gunther Migeotte gunther@cae.co.za, [Msgid=431135]
Evenrude Jetstream

ViewThread

Practical Mechanics

[Date/Time=05-09-2003 – 11:35 AM]

Name:Barney C. Black webmaster@foils.org, [Msgid=433017]
Re; Evenrude Jetstream

[Date/Time=05-12-2003 – 1:01 PM]

Name:Steve Rhodes srhodes@domus-usa.com, [Msgid=434280]
Re; Evenrude Jetstream

[Date/Time=05-15-2003 – 9:12 AM]

Name:Martin Grimm seaflite@alphalink.com.au, [Msgid=435860]
Hydrofoil Museum in CFF

http://home20.inet.tele.dk/cff/pdf/cff_2003_3.pdf

Is the Hydrofoil Ready for the Museum? –Or Is the World Ready for a Hydrofoil Museum?

[Date/Time=05-28-2003 – 7:18 PM]

Name:Ken Spaulding kboyd@erols.com, [Msgid=443291]
Unknown Hydrofoil CYRA

ViewThread

[Date/Time=06-01-2003 – 12:26 PM]

Name:Christof Schramm c_schramm@T-Online.de, [Msgid=445206]
Attached File “Cyra~jpg.zip” – size 784238 Click Here To Download
Re; Unknown Hydrofoil CYRA

www.britishpathe.com

[Date/Time=06-02-2003 – 3:26 PM]

Name:Eje Flodstrom eje_flodstrom@yahoo.com, [Msgid=445885]
1980s Vessel

ViewThread

[Date/Time=06-02-2003 – 7:51 PM]

Name:Cary Holmes csholmes77@hotmail.com, [Msgid=446013]
Re; 1980s Vessel

https://archive.foils.org/gallery/world.htm
[Date/Time=06-02-2003 – 8:00 PM]

Name:Barney C Black webmaster@foils.org, [Msgid=446017]
PS-30 Jetfoil in KOREA

http://www.mirejet.com/images/mirejet.wmv

[Date/Time=06-10-2003 – 4:37 AM]

Name:Kevin Tse kevin@softrepublic.com, [Msgid=449829]
PGH-2 TUCUMCARI Veteran

[Date/Time=06-14-2003 – 7:21 PM]

Name:james “jimmy” trussell jtbaseball@i-55.com, [Msgid=452819]
PHMRON 2 veterans

ViewThread

[Date/Time=06-16-2003 – 4:55 AM]

Name:steve novell (Jolly-OS1, PHM1) sjnovell@mindspring.com, [Msgid=453350]
Turtle Krawls

ViewThread

[Date/Time=06-17-2003 – 4:45 AM]

Name:Barney C Black webmaster@foils.org, [Msgid=454016]
PCH-1 Highpoint photo

ViewThread

[Date/Time=06-26-2003 – 1:42 PM]

Name:Bob Cline clinewlt@pacifier.com, [Msgid=460196]
Attached File “HighPoint~jpg.zip” – size 392650 Click Here To Download
Re; PCH-1 Highpoint photo

HIGHPOINT

https://archive.foils.org/highpt.htm

https://archive.foils.org/gallery/usn.htm

http://rpstander.tripod.com/

[Date/Time=06-28-2003 – 7:34 AM]

Name:Barney C Black webmaster@foils.org, [Msgid=461174]
Re; Turtle Krawls

[Date/Time=06-29-2003 – 2:00 PM]

Name:steve novell steve.novell@novellfamily.com, [Msgid=461681]
Hydrofoil Waterski History

[Date/Time=07-13-2003 – 7:12 AM]

Name:Barney C Black webmaster@foils.org, [Msgid=469001]
PHM-5 Historic Significance

http://www.ussaries.org
[Date/Time=08-08-2003 – 4:46 PM]

Name:Eliot James esjames@cvalley.net, [Msgid=484403]
PHM Reunion With a PHM

http://www.ussaries.org
[Date/Time=08-08-2003 – 4:49 PM]

Name:Eliot James esjames@cvalley.net, [Msgid=484404]
Yamaha OU-32 Page is Gone

ViewThread

http://www.yamaha-motor.co.jp/cp/challenge/expansion/ou32/ou32.html
[Date/Time=09-03-2003 – 7:27 PM]

Name:Doug Bedient doug@ahfactory.com, [Msgid=499932]
Re; Yamaha OU-32 Page is Gone

ViewThread

http://www.archive.foils.org

horiuchi@ta2.so-net.ne.jp

[Date/Time=09-03-2003 – 7:47 PM]

Name:Barney C Black webmaster@foils.org, [Msgid=499951]
Re; Re; Yamaha OU-32 Page is Gone

[Date/Time=09-04-2003 – 2:09 PM]

Name:Scott Smith ssmith@syntheon.com, [Msgid=500719]
Hydrofoils on the History Channel

TUCUMCARI

[Date/Time=09-23-2003 – 7:06 PM]

Name:Martinn Mandles MHMandles@aol.com, [Msgid=513075]
PIAGGIO P7 Hydroplane

ViewThread

http://aeroweb.lucia.it/en/history/pegna2.htm

[Date/Time=10-03-2003 – 9:45 AM]

Name:Paolo Chiarlone PChiarlone@piaggioaero.it, [Msgid=519053]
Image Attached: “P7_trittico.gif” Click Here To View
Re; PIAGGIO P7 Hydroplane

[Date/Time=10-07-2003 – 9:16 AM]

Name:Martin Grimm seaflite@alphalink.com.au, [Msgid=520942]
Re; Re; PIAGGIO P7 Hydroplane

http://digilander.libero.it/dbmontello/Forlanini.htm

http://www.angelfire.com/sports/aeromodelismelutry/Fichier_histoire/1920_piaggiopc7.htm
http://www.angelfire.com/sports/aeromodelismelutry/Fichier_maquettes/piaggiopegnapc7.htm

[Date/Time=10-09-2003 – 8:43 AM]

Name:Paolo Chiarlone PChiarlone@piaggioaero.it, [Msgid=522263]
Image Attached: “P7_BrevettoPegna_1.jpg” Click Here To View
Re; Re; Re; PIAGGIO P7 Hydroplane

[Date/Time=10-15-2003 – 9:30 AM]

Name:Bill White whitewn@speakeasy.net, [Msgid=525587]
Jetfoil Photos Required

ViewThread

kevin@softrepublic.com

[Date/Time=02-06-2004 – 11:57 AM]

Name:Kevin Tse kevin@softrepublic.com, [Msgid=585321]
Re; Jetfoil Photos Required

https://archive.foils.org/gallery/jetfoil.htm

[Date/Time=02-08-2004 – 9:13 PM]

Name:Bill White whitewn@speakeasy.net, [Msgid=593148]
High Point Web Site

ViewThread

http://rpstander.tripod.com/

[Date/Time=02-17-2004 – 5:04 AM]

Name:Kevin Tse kevin@softrepublic.com, [Msgid=598125]
Re; High Point Web Site

[Date/Time=02-17-2004 – 12:34 PM]

Name:IS. Arima arimas1@juno.com, [Msgid=598273]
Jetfoil around the World

[Date/Time=02-26-2004 – 8:09 AM]

Name:Felix Ng felisvoski@yahoo.com.hk, [Msgid=603757]
Ships That Fly

http://themeyers.org/ShipsThatFly/index.html

jr8meyer@comcast.net
[Date/Time=03-17-2004 – 4:51 PM]

Name:John R. Meyer jr8meyer@comcast.net, [Msgid=616012]
MK 75 MOD 1 Gun System ISEA

ViewThread

Jerry.Grasmick@navy.mil
[Date/Time=04-09-2004 – 4:31 PM]

Name:Jerry R. Grasmick Jerry.Grasmick@navy.mil, [Msgid=628849]
Image Attached: “PHM2&3.JPG” Click Here To View
Re; MK 75 MOD 1 Gun System ISEA

https://archive.foils.org/gallery/phm.htm

[Date/Time=04-10-2004 – 10:29 AM]

Name:George Jenkins georgejj@aol.com, [Msgid=629061]
Re; MK 75 MOD 1 Gun System ISEA

[Date/Time=04-12-2004 – 9:34 AM]

Name:Jerry R. Grasmick Jerry.Grasmick@navy.mil, [Msgid=629731]
Re; MK 75 MOD 1 Gun System ISEA

[Date/Time=04-12-2004 – 12:46 PM]

Name:George Jenkins georgejj@aol.com, [Msgid=629842]
Hydrofoil Magazine Collection For Sale

ViewThread

https://archive.foils.org/popmags.htm

NOT

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=4207059447

[Date/Time=04-24-2004 – 11:21 AM]

Name:Barney C. Black barney@alum.mit.edu, [Msgid=636332]
Hydrofoil Magazine Collection For Sale

[Date/Time=05-04-2004 – 5:00 PM]

Name:Barney C Black bcblack@erols.com, [Msgid=641704]
Ex Crewmember

[Date/Time=05-28-2004 – 9:09 PM]

Name:Joe Landrum joekay45@earthlink.net, [Msgid=655670]
Ex Crewmember

[Date/Time=05-28-2004 – 9:09 PM]

Name:Joe Landrum joekay45@earthlink.net, [Msgid=655671]
Hydro Foil Book

ViewThread

[Date/Time=06-24-2004 – 12:17 AM]

Name:John Halstead amo@qldnet.com.au, [Msgid=668953]
Easy Source of 20 Foilborne Years Book

https://archive.foils.org/ihspubs.htm#AMV
[Date/Time=06-29-2004 – 8:01 PM]

Name:Barney C Black bblack11@cox.net, [Msgid=672134]
Baker boats

ViewThread

[Date/Time=07-12-2004 – 8:25 PM]

Name:Neil nlien@inwave1.com, [Msgid=678439]
Re; Baker boats

http://themeyers.org/ShipsThatFly/

[Date/Time=07-14-2004 – 5:14 AM]

Name:Barney C Black barney@alum.mit.edu, [Msgid=679266]
AGEH-1 Plainview Plans

[Date/Time=07-17-2004 – 10:53 PM]

Name:James H. Valkyrie@whoever.com, [Msgid=681312]

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Design of Foils

The International Hydrofoil Society (IHS) Hydrofoil Correspondence Archives

Updated last August 20, 2006

Design of Foils: Foil-Struts-Controls-Performance

Design of Foils: Foil-Struts-Controls-Performance Top

Count,MessageID,category,ShortTitle,Message,Date,UserName,MsgPswd,Phone,Email,ParentMsgId

“1”,”950336″,”2″,”Re; Re; Revolutionizing a watersport||950336″,”Good response, Tom. When you say ” it’s much better to specify the pressure distribution and then calculate the section shape that will produce it. Would you be suggesting to use Xfoil to do the calculation?”,”2005-12-20″,”Ray Vellinga”,”nopswd”,” “,”rvell@san.rr.com”,”949055″

“2”,”949055″,”2″,”Re; Re; Revolutionizing a watersport||949055″,”I don’t think the radius+ogive middle is a very good way to go. That was the philosophy behind my Proa 1-series.

The sudden change in curvature at the junction between the ogive and radius caused a sharp pressure spike:

This, in turn, led to laminar separation, premature stall from the leading edge, and increased drag. Separation near the leading edge is especially bad for a hydrofoil, because it leads to ventilation and the sudden loss of three-quarers of the lift.

So, while ogive sections may be easy to construct, I’m not enamored with their hydrodynamics.

Today, it’s much better to specify the pressure distribution and then calculate the section shape that will produce it. That way you can see what needs to be fixed in the hydrodynamics and go after it directly instead of shooting in the dark by modifying the geometry. “,”2005-12-17″,”Tom Speer”,”nopswd”,” “,” “,”946625”

“3”,”946625″,”2″,”Re; Re; Revolutionizing a watersport||946625″,”Tom Speer, any discussion of ogival hydrofoils sections is of interest to me. I have made and flown several such foils. They are easy to construct by welding a rolled piece of metal plate to a flat metal plate and then grinding to make the welds fair.

You have mentioned the idea of adding a radius to the leading edge of the ogival foil. This could be done by welding the forward edges of the top and bottom plates to a rounded section–a tube or a bar. Two questions: Do you have some guidelines on choosing a radius to the rounded leading edge? And, is the junction between the rounded edge and the top plate and the bottom plate a big problem? Would you think this to be a difficult transition?”,”2005-12-12″,”Ray Vellinga”,”nopswd”,” “,”rvell@hotmail.com”,”945783″

“4”,”945783″,”2″,”Re; Revolutionizing a watersport||945783″,”Yes, it’s possible to design fore-aft symmetric foils that will work equally well in both directions. You basically have two possible approaches: sharp-edged, and rounded edges.

Examples of the sharp-edged foils are the ogival that have been used by may hydrofoil designers. They have the advantage of being simple to construct and have low drag within their design range of angles of attack. The problem with sharp leading edges is they only have a small range of angles of attack at which the flow is attached. Outside that range, they experience leading edge separation. This can lead to sudden ventilation – a charactersitic that has bedeviled many craft that use these sections. You can find section data for ogival sections published in the literature and in books like Hoern’er’s “Fluid Dynamic Drag”.

The round-edged approach promotes leading edge suction for low drag and does not necessarily suffer from leading edge stall. There will be a separated zone at the trailing edge which can cause some increased drag. Elliptical sections have been used for some stopped-rotor VTOL aircraft.

To the best of my knowledge, the only round-edged sections specifically designed for use as hydrofoils can be found at http://www.basiliscus.com/ProaSections/ProaIndex.html. XFOIL predicts the Proa-3 series sections have performance comparable to NACA 6-series sections.

“,”2005-12-10″,”Tom Speer”,”nopswd”,” “,” “,”935018”

“5”,”942165″,”2″,”Foil works in forward or reverse direction||942165″,”You haven’t said specifically which watersport you want to revolutionize, but I’m pretty sure I know. I won’t say it outright here because you seem to be concerned with someone stealing your idea. I have had discussions with others wanting to do the same thing, and have evaluated some of the pitfalls. If you drop me a line at tothebin@adelphia.net, I’ll send you my contact info and we can talk, I’m in Stuart Florida. I may not have the ultimate answer for you, but I think I can help.”,”2005-12-03″,”Scott Smith”,”nopswd”,” “,”boatswithwings@adelphia.net”,”941596″

“6”,”941596″,”2″,”Foil works in forward or reverse direction||941596″,”Nat,
I appreciate your response, but have no idea what you said. I’m not familiar with a “soft” foil. I have so many questions, I feel I’m just going to be more of a burden than anything on here. But again, I am willing to pay someone for their time. Also, maybe there is somewhere I can go for more info, I have tapped the internet for all its worth.

Thanks to all,
Derek”,”2005-12-02″,”Derek”,”nopswd”,” “,”Derekseaman@gmail.com”,”941408″

“7”,”941408″,”2″,”Foil works in forward or reverse direction||941408″,”I SUGGEST THAT YOU CONSIDER A SOFT FOIL OVER A RIGID SPAR FOR SAFETY. ALSO, IF PROPERLY DESIGNED IT COULD BE INHERENTLY STABLE. (THAT IS IT WOULD DEFORM TO REDUCE THE ANGLE OF ATTACK IF STALL APPROACHES.) NAT K”,”2005-12-02″,”NAT KOBITZ”,”nopswd”,” “,”kobitzn@ctc.com”,”940695″

“8”,”940695″,”2″,”Foil works in forward or reverse direction||940695″,”Thank you all for your help. Unfortunately, I am still unsure if the design I have in mind is possible. There are many variables that are not taken into consideration with hydrofoil boat designs that I have to think about. For example, instead of proplusion, this board will be towed, and the rider of the board will be able to manipulate the board in ways we could not with a boat. If there is anyone that would be willing to give me a little more in depth advice, possibly over the phone, or in person (I live in Orlando), I would be more than willing to pay for your time. I need to first determine whether it would be physically possible to do what I want, and then if it is, I would have to explain some of the problems that might arise that are not addressed with any other hydrofoil. If all goes well, I would like to make a few prototypes, and start a company that would revolutionize the fastest growing watersport.

Thanks for everyone’s time,
Derek Seaman
407-739-1827″,”2005-12-01″,”Derek”,”nopswd”,” “,”derekseaman@gmail.com”,”938319″

“9”,”938319″,”2″,”Foil works in forward or reverse direction||938319″,”A complete copy of this 57 page report is in my hands. Today I offered it to Barney Black to be posted on the IHS site. If he accepts, you can download it from there soon.

I have used the Ogival sections with some success. They are useful because they can be built easily using sheet metal, a welder and a metal grinder.”,”2005-11-26″,”Ray Vellinga”,”nopswd”,” “,” “,”935301”

“10”,”938089″,”2″,”Re; Hydro foil designs||938089″,”Go to a good technical library and take out a copy of “Theory of Wing Sections” by Ira Abbott and Von Doenhoff, by Dover Publications, Inc., NY c 1959.

All the airfoil sections described there will work as foils. The charts shown for lift and drag coefficients will be accurate for air or water. Just remember that water is 800 times more dense that air so the resulting speed, lift, drag, etc. will differ accordingly. “,”2005-11-26″,”Ray Vellinga”,”nopswd”,” “,” “,”935322”

“11”,”935334″,”2″,”Foil drag, size vs. angle of attack||935334″,”Ray, you seem to know what you are talking, about please look at my posting and see if you have any input.
Thanks
Dan Bush”,”2005-11-20″,”Dan Bush”,”nopswd”,” “,”lostboys81@bellsouth.net”,”918835″

“12”,”935322″,”2″,”Hydro foil designs||935322″,”I have a 1973 Carri Craft Catarmaran. Full displacement hulls. Lenght 57″, beam 12′.If I did the calculations correctly theoritcal hull speed is close to 20 knots. I am not willing to repower or pay the fuel penalty for this speed. I should mention I have lived on /traveled in this boat for three years and the following speeds and fuel economies are from more than 1000 hours of travel,deterimined by gps. While in drydock two years ago I added three fins/stabilizers on each hull, 8″ wide and 8′ long. This solved the problem of excessive roll at anchor or docked. When I added these fins I expected to lose a knot or more due to extra drag. Much to my surprise and pleasure I actually picked up a knot in speed. Boat weighs approximately 38,000 lbs empty, has twin Isuzu 150 horse diesels, and the best speed I have gotten out of her to date has been a little over 12 knots at 2400 rpm slinging 20×20 four bladed nibrile props. I have solved an over heating problem and can now go to a continous 2700 rpm. Fuel effiency at 9 knots is(I am not a liar, normally I tell people three knots per gallon) 4 knots per gallon at approximately 50,000 lbs gross weight. Currently I am in dry dock and it occurred to me that by reshaping my stabilizers as hydro foils I could gain more speed. I need foil designs. It seems that the strenght of my stabilizers is sufficient to support the weight of the boat. Idiots ran STRAPS over the fins and lifted my boat with no damage.They moved it while I was not present from one place to another in the yard. The front fin is canted upwards three inches out of level which I suspect is the reason for my speed gain. I currently have helicopter foil designs which I may expand out to eight feet and install. It seems to me with the front fin pitched 3% higher then the middle and last foil like Burt Rutans designs the level of the boat should be limited by stalling of the front first. I am seriously contemplating adding trim control but before I do this I would like to add hydrofoils and play with it for six months.
I should add that I am a fully competent welder, actually “enjoy” fiberglass work, can wander around a machine shop and identify a tool or two. Feed back on hydro foil shapes would be greatly appreciated. This is not “pie-in the sky”, I will be modifying my stabilizers in the next few weeks. Your help will be greatly appreciated and is worth a wild time out fishing, or traveling to some exoctic port to get into exoctic trouble.”,”2005-11-20″,”Dan Bush”,”nopswd”,” “,”lostboys81@bellsouth.net”,”2″

“13”,”935307″,”2″,”Foil works in forward or reverse direction||935307″,”I have a photocopy of a few pages of Report No. E-79-6 “WATER TUNNEL OBSERVATIONS ON THE FLOW PAST A PLANO-CONVEX HYDROFOIL”, by R.B. Wade, February 1964, Division of Engineering and Applied Science, CALIFORNIA INSTITUTE OF TECHNOLOGY, Pasadena, California. On the cover page, it also says “Office of Naval Research Department of the Navy Contract Nonr-220(24)”, and “D.J.Nigg” in handwriting. I forget where I got it, maybe from Donald Nigg himself. Is he still making foils?

Anyways, the paper gives lift & drag data for a foil with an “ogive” section. That means straight line on the bottom, circular arc on the top. The model used for testing is 0.19″ thick, with a chord length of 2.77″. At zero degrees angle of attack CL is 0.4 and CD is 0.013. This would be the same forward or reverse.

Maybe someone with access to the whole report could get it posted on the IHS website. As a last resort, I could scan what I have, but it’s incomplete. Not sure about the copyright issues here.”,”2005-11-20″,”Mac Stevens”,”nopswd”,” “,”stevensm@earthlink.net”,”935018″

“14”,”935301″,”2″,”Foil works in forward or reverse direction||935301″,”I have a photocopy of a few pages of Report No. E-79-6 “WATER TUNNEL OBSERVATIONS ON THE FLOW PAST A PLANO-CONVEX HYDROFOIL”, by R.B. Wade, February 1964, Division of Engineering and Applied Science, CALIFORNIA INSTITUTE OF TECHNOLOGY, Pasadena, California. On the cover page, it also says “Office of Naval Research Department of the Navy Contract Nonr-220(24)”, and “D.J.Nigg” in handwriting. I forget where I got it, maybe from Donald Nigg himself. Is he still making foils?

Anyways, the paper gives lift & drag data for a foil with an “ogive” section. That means straight line on the bottom, circular arc on the top. The model used for testing is 0.19″ thick, with a chord length of 2.77″. At zero degrees angle of attack CL is 0.4 and CD is 0.013. This would be the same forward or reverse.

Maybe someone with access to the whole report could get it posted on the IHS website. As a last resort, I could scan what I have, but it’s incomplete. Not sure about the copyright issues here.”,”2005-11-20″,”Mac Stevens”,”nopswd”,” “,”stevensm@earthlink.net”,”935018″

“15”,”935018″,”2″,”Revolutionizing a watersport||935018″,”I think the use of foils may change the watersport I love. Unfortunately, I cannot seem to find the information I need to make a basic hypothesis on the design. Every hydrofoil I have seen is based upon moving in one direction (boats don’t reverse at high speeds). Is it possible to have a hydrofoil design that allows movement in opposite directions and will perform well either way? If you could imagine a symmetrical jet propelled boat, so that it could go backwards or forwards either way. Any help would be appreciated.”,”2005-11-19″,”Derek”,”nopswd”,” “,”derekseaman@gmail.com”,”2″

“16”,”931880″,”2″,”Re; Assistance wanted – foil design||931880″,”Dear Bob,

Please give me a call or send me your phone number and email contact.
You can call me on (203) 313 4061.

My company, Hydrofoil Assisted Water Craft HAWC Technologies was recently formed.

We work to help people like you, and believe we will have a solution for you. We need to assess your vessel’s basic information first in order to do a speed prediction based upon the vessel’s length, displacement weight and power amongst some other info.

Looking forward to talking with you.

BR
Gerhard “,”2005-11-14″,”Gerhard Kutt”,”nopswd”,” “,”caemarine@earthlink.net”,”926828″

“17”,”926832″,”2″,”Assistance wanted – Foil design||926832″,”We have a 24 meter commercial Catamaran with a cruising speed of approx. 25 knots with full load. We plan to retrofit the vessel with “aasisting” foils.
We are looking for an hydrofoil expert that can assist in the design and technical specification of “assisting” foils that will be placed between the hulls of the Cat. The goal is to reach a cruising speed of approx 27-28 knots and with a lower the fuel consumption than today. (if possible)!

Best regards, Bob Email: swedbob@hotmail.com”,”2005-11-05″,”Bob”,”swedbob”,” “,”swedbob@hotmail.com”,”2″

“18”,”926828″,”2″,”Assistance wanted – foil design||926828″,”We have a 24 meter commercial Catamaran with a cruising speed of approx. 25 knots with full load. We plan to retrofit the vessel with “aasisting” foils.
We are looking for an hydrofoil expert that can assist in the design and technical specification of “assisting” foils that will be placed between the hulls of the Cat. The goal is to be able to reach a cruising speed of approx 27-28 knots and lower the fuel consumption.

Best regards, Bob”,”2005-11-05″,”Bob”,”swedbob”,” “,”swedbob@hotmail.com”,”2″

“19”,”925912″,”2″,”Foil drag, size vs. angle of attack||925912″,”I appreciate the feedback, but it wasn’t really what I was asking. I’m not trying to determine the optimum foil size or profile at this time. I am trying to find out at a fixed speed and weight, which has less drag, a larger foil at lower angle of attack, or a smaller foil at higher angle of attack. A perfectly trimmed hydrofoil boat (without active controls) will perform quite differently if the overall weight or weight distribution changes. I see three directions to attack this problem. One is to have foils sized and trimmed for optimum performance when the boat is lightest, then increase the angle of attack when the boat is heavy. The second is to size and trim the foils for the boat at its heaviest, then run the foils at a reduced angle of attack when the boat is lighter. The third is of course to size and trim the foils at a point halfway between the weights, and then re-trim accordingly as the weight changes. I’m trying to figure out which will have the least drag penalty when run at the most commonly used weight.”,”2005-11-04″,”Scott Smith”,”nopswd”,” “,”boatswithwings@adelphia.net”,”920315″

“20”,”920315″,”2″,”Foil drag, size vs. angle of attack||920315″,”Check your data. I believe it is in error.
NAT KOBITZ”,”2005-10-26″,”NAT KOBITZ”,”nopswd”,” “,”kobitzn@ctc.com”,”918835″

“21”,”918835″,”2″,”Foil drag, size vs. angle of attack||918835″,”Scott Smith: Look on page 522 and 523 of “Theory of Wing Sections” By Abbot & Doenhoff for the
best Lift over Drag ratio, L/D for the wing section NACA 63412. This section is in common use.
The best L/D is at about Coefficient of Lift = .4. This occures at -6 degrees Angle of Attack.
The Excel formula attached determines that the area should be 1.32 square feet.
If your cord were 4.75 inches, the span should be 40.1 inches.
“,”2005-10-24″,”Ray Vellinga”,”nopswd”,” “,”rvell7829@yahoo.com”,”917973″

“22”,”917973″,”2″,”Foil drag, size vs. angle of attack||917973″,”This is a rather simple question, and I hope there is a simple answer, but here goes: I am looking at the design of a foil wing that must support a fixed weight at a fixed speed, let’s say 1000 pounds at 30 mph. Which has less drag, a larger foil at lower angle of attack, or a smaller foil at higher angle of attack? Other considerations such as stall angle are not important.”,”2005-10-22″,”Scott Smith”,”nopswd”,” “,”boatswithwings@adelphia.net”,”2″

“23”,”917248″,”2″,”Re; Stevenson SportFoiler Published||917248″,”This is indeed good news, as there have been many requests over the years for these plans. IHS should ask permission to reprint them in the next hydrofoil CD-ROM”,”2005-10-20″,”Barney C Black”,”poopdeck”,” “,” “,”916786”

“24”,”916786″,”2″,”Stevenson SportFoiler Published||916786″,”Stevenson Projects produced a set of plans for the SportFoiler, a single person surface-piercing hydrofoil. Unfortunately, several years ago they abruptly discontinued the plans, although many of us have asked for them.

To my delight, Stevenson Products has published the plans (for free!!) online. The address is: http://www.stevproj.com/TheSportfoilPlans.pdf

I want to thank the people at Stevenson, as this project shows just how easy hydrofoils are to build. Don’t dismiss these plans. “,”2005-10-19″,”Barry Steele”,”nopswd”,” “,” “,”2”

“25”,”908696″,”2″,”Re; Req for Technical Paper||908696″,”I don’t have a copy of the paper; however you may be interested in the following excerpt from IHS archival correspondence taken from www.foils.org/students.htm, and you may want to try the email contact:

[18 Jan 01] We were sort of toying with the idea of using supercavitating foils. Do any of you know where I can get some good information on supercavitating foil sections, or the design of supercavitating hydrofoil vessels. I don’t remember who asked, but I am pretty sure we are just doing our hull with FastShip and then doing analysis using NavCad. If you have a better suggestion (which can be handled at an undergraduate level) Id love to hear it as well. — Earon S. Rein, MIDN USN (m015346@nadn.navy.mil)

Responses…

[18 Jan 01] Two suggested sources:

Altman, R., “The Design of Supercavitating Hydrofoil Wings,” Technical Report 001-14, Hydronautics Inc., April 1968.
Martin, M., “The Stability Derivatives of A Hydrofoil Boat – Part II”, Technical Report 001-10(II), Hydronautics Inc., January 1963.
[18 Jan 01] The best info I’m aware of on supcav foil sections is the Carderock work in the 1970s on the “TAP-2” series of base-vented supercavitating foils. The work may have been done by Young Shen but I’m not sure. — Mark Bebar (bebar@foils.org)

“,”2005-10-06″,”Barney C Black”,”poopdeck”,” “,” “,”904808”

“26”,”904808″,”2″,”Req for Technical Paper||904808″,”Where can I find this paper Altman, R., “The Design of Supercavitating Hydrofoil Wings,” Technical Report 001-14, Hydronautics Inc., April 1968[. Can somebody email me the pdf version of this paper at the following mp_mathew@hotmail.com.”,”2005-10-01″,”M.P. Mathew”,”nopswd”,” “,”mp_mathew@hotmail.com”,”2″

“27”,”889045″,”2″,” Supercavitating Foils||889045″,” I have to design supercavitating hydrofoils for a hydrofoil vessel going upto a max speed of 70 knots. I was thinking of going for Tulin’s sections. But I also know that the L/D charecteristics for this type of sections below 40 kts would be absymally poor. Am I correct? Can I use the public domain XFOIL(by Mark Drela) for getting the fully wetted Lift and Drag charecteristics for these sections for the non cavitating regime(upto 40 knots)or is XFOIL not suitable for sharp leading edge profiles.

My second question: Can I use base ventilated tulin section foils so that I can get supercavitating regime even at low speeds. How are supercavitating flows and base ventillated foils related. Can I use linearized Tulin’s theory for base ventillated foils. Are base ventillated foils approaching sigma (cavitation no.) = 0 . How do i get the lift and drag coefficients for base vented foils otherwise. Any references will be highly appreciated. Thanx
“,”2005-09-06″,”MP Mathew”,”nopswd”,” “,”mpmathew73@yahoo.com”,”2″

“28”,”888679″,”2″,”Re; Question on fully submerged foils||888679″,”My Dynafoils use a fixed rear foil, fully submerged. The front foil is a simple mechanical system, fully submerged foil coupled to a surface follower. There are no other controls except steering and throttle. It can be a handfull to control at times, but only because it is short, with deep foils and lots of power. At moderate power levels and reasonbly calm seas it handles just fine, with no roll control aparatus or trimming of the foils needed. On smaller boats with less roll moment, steering works just fine to control roll issues.”,”2005-09-05″,”Scott Smith”,”nopswd”,” “,”boatswithwings@adelphia.net”,”872569″

“29”,”888667″,”2″,”Re; Cheap ready made hydrofoils?||888667″,”I have copies of the old Popular Science articles on how to make wooden foils cheaply, with a tablesaw. Would work very well for you. Drop me a line and I’ll e-mail them to you, free.”,”2005-09-05″,”Scott Smith”,”nopswd”,” “,”boatswithwings@adelphia.net”,”2″

“30”,”884493″,”2″,”Re; Idea; Use Air to Bank Turns||884493″,”Grant,

Your proposal to use air feed to control the lift force on a hydrofoil is a sensible one. So sensible in fact, that it has been successfully implemented on both small and large hydrofoils!

The name most commonly applied to this method of hydrofoil stabilisation is “controlled ventilation”. In this context, the term “ventilation” refers to air being drawn down to the foils. On the other hand “cavitation” refers to water changing state to ‘steam’ due to very low pressure as sometimes occurs on hydrofoils so isn’t as accurate a description of what is happening.

My understanding is that this concept was first practically applied by the Swiss based company Supramar headed up by the hydrofoil pioneer Baron Hans von Schertel. Early experiments were carried out on a Supramar ST 3A fully submerged air-stabilised hydrofoil research craft. Later, various large passenger hydrofoils adopted the concept, in particular the Supramar PT 150 of which three were built. My understanding is that air stabilisation may have variously been used to assist with roll, pitch and heave stabilisation of hydrofoil.

Hans von Schertel wrote a number of technical papers on this concept at the time pointing out its advantages over conventional flapped hydrofoils. None the less, it never seems to have achieved widespread application. I don’t know why.

You would be able to find out more details if you can gain access to early issues of Jane’s Surface Skimmers or the journal “Hovering Craft and Hydrofoil” from the 60’s.

In more recent years, there had been renewed interest in foil stabilisation using air feed. A research project in Australia had considered this approach for use in controlling lift on motion control foils (for catamarans and the like). In that case, the concept had been referred to as “lift dumping foils”. I don’t believe this progressed to any operational systems.

I was not aware of any Italian research / patents on this concept but would be interested to hear more about that.

Good luck with your own experimentation.

Martin”,”2005-08-28″,”Martin Grimm”,”nopswd”,” “,”seaflite@alphalink.com.au”,”883043″

“31”,”883043″,”2″,”Re; Idea; Use Air to Bank Turns||883043″,”I believe this type of foil control is called artificial cavitation. I am not sure what or how much effect it has on foils at different speeds. It may not be enough effect to control the boat. The Italian patent was for large fast ferries carrying a couple of hundred passengers. I don’t think it was ever used. I think that Boeing may have investigated this idea too. I believe they held a few patents for artificial cavitation in other forms as well. I was thinking it might have application in smaller recreational boats.

My first test will be to try to improve the turning ability of My Volga. A 90-meter turning radius is not exactly turning on a dime (with very little banking). My first trial will be to use some 1” rubber hose and a lot of duct tape. Two hoses (port and starboard) will run from the cockpit to the bow and down to the center two struts (of 4) on the front foil the hose will end right at the top of the foil. A valve at the cockpit controls the airflow. Massive amounts of duck tape should smooth out the bump the hose will make as it goes down the strut. The strut is not hollow; it is made of 1/4’” stainless steel. Any ideas?
“,”2005-08-25″,”Grant Calverley”,”nopswd”,” “,”grant@sanjuantimberframes.com”,”882728″

“32”,”882728″,”2″,”Re; Idea; Use Air to Bank Turns||882728″,”Revision #1 of Idea
On rethinking it seems air passages on from the struts to the foils should not be crossed from port to starboard and visa versa. On a boat unevenly loaded or running parallel to waves it would not right its self. It could even get dangerous as the heavy side of the boat would lose lift and sink even lower. The lower it sinks the greater the lift on the opposite side. Opps bit of a problem. It would be easier to make a foil without the cross over air tube feature anyway.

Another benefit to not having it cross over is after an operator initiated banked turn is complete the boat would right itself automatically. The lower (deeper) side would have more lift than the upper side creating a righting effect. The operator initiated banked turn air system would need to override or supply more air than the altitude control air system. The two systems would be somewhat fighting each other.
“,”2005-08-24″,”Grant Calverley”,”nopswd”,” “,”grant@sanjuantimberframes.com”,”882721″

“33”,”882721″,”2″,”Idea; Use Air to Bank Turns||882721″,”Hello,

I have been kicking around a simple idea for stabilizing fully submerged foils for a long time. I did a patent search a while back and found that an Italian had patented a very similar idea for fast hydrofoil ferries before I was born in 1963. It seems like a good Idea so I will attempt to describe it. Maybe some one else can use the idea and make it real. I am not an engineer but would be interested to have some feedback.

The system would have almost no moving parts. It would use hollow struts and foils. Air supplied to the tops of the foils to reduce lift would main mechanism for stability, banked turns and attitude control. Two separate sets of holes on the port and starboard sides of the foils (like holes on a flute) would be across the top in the low-pressure area.

Banked Turns. When a banked turn to the right is desired an air is supplied to the right side of the foil decreasing its lift creating a banked turn. The mechanism could be as simple as a two tubes and valves (for port and starboard turns) near the steering wheel. Open the valve just before starting your turn. Electronically a turn signal lever like on a car would work well and is already instinctive to use. I have a Volga 70 and may try a duck tape and plastic hose version of this banked turn concept next year. (when I get it running)

Altitude Control and Stability. The banked turns would require some mechanical input to initiate. Attitude control would be automatic and may require a separate set of holes from the banked turn set. The line of holes on the top surface of the starboard side of the foil would be connected through the hollow foil to a corresponding set of holes in the side of the strut on the port side of the boat. At slow speeds all of the holes in the strut would be below the surface. As the boat gains speed the strut raises out of the water and the first of a serious of holes is exposed to the air. The low pressure of the wing sucks the air down through the hole and reduces the lift slightly. As the boat speeds up more holes are exposed and the lift is reduced even more maintaining equilibrium in altitude. Having the air lines cross from port strut to starboard foil and vies versa would aid in banked turns.

There are a few problems /questions in my mind. 1) Is there enough suction on the top surface of the wing to suck the air down the tubes and blow out the water that would be there already? Would you need compressed air?.(the Italians used compressed air and some complicated sensors from what I remember) 2)The hole’s orifices would need to be sized and located very carefully. Not to big and not too little. 3) Would there be a big lag time as the water is pushed out of the struts and hollow foils. 4) At slower speeds water would circulate through the strut and foils holes, would this effect lift? 5) Would the boat right its self after completing a banked turn?

I would appreciate some feedback and may try some simple experiments on my Volga next year if it is warranted. What do you think, does it have merit or is it flawed? I never even took Physics in high school so go easy on me.

Grant Calverley
“,”2005-08-24″,”Grant Calverley”,”nopswd”,” “,”grant@sanjuantimberframes.com”,”2″

“34”,”872638″,”2″,”wsome Re; Re; Re; FOIL SHAPE AND AN||872638″,”Awsome answer. Thank you Tom.
I have already experienced much of what you have discussed. I actually started with a low angle, and found that the drag of the foils actually pulled the boat down. I compensated by doubleing the front angle, and that helped. I had already preset the rear foils at an angle of six degrees. So by end of testing on the first day, it came down to the fact that my jet pump could not supply enough thrust.
I have doubled the size of the pump, and have created a four bladed impeller. I also have an output reduction cone built to see if reducing the output diameter doesn’t increase the speed of the output.
I have several things to try including two more motors.

I was hoping to get 12mph, and the first pump failed miserbley.
I don’t think I will have any chances at the pond till next weekend

Thank you

“,”2005-08-06″,”Umi_Ryuzuki”,”nopswd”,” “,”umi_ryuzuki@hotmail.com”,”872597″

“35”,”872597″,”2″,”Re; Re; FOIL SHAPE AND ANGLE||872597″,”You have the basic idea, but I think you’re missing a couple of things. You do get the area by assuming lift = weight and dividing by the dynamic pressure and design lift coefficient. But you have to use consistent units.

The factor F in your formula is the fluid density divided by 2. For water, the density is (using your English units) 1.939 slug/ft^3, so the Factor F should be 0.9695 for fresh water, or pretty close to 1.

The velocity has to be in ft/sec to be consistent, so I’ll take the “12” in your calculations as being 12 ft/sec (same as 8.2 mph or 7.1 kt). The velocity has to be squared, which I’m not sure you did to come up with your final result.

So at a speed of 12 ft/sec and a lift coefficient of 0.5349, I get an area of 0.067 sq ft or 9.64 sq in for the required area. Since each of your wings have an area of 7.5 sq in, getting the 5 lb of lift from 6 of them is not a problem. The extra area will let you fly at half the design speed of 12 ft/sec.

However, while the average lift coefficient may be 0.5349, that doesn’t mean the local lift coefficient will be the same over all parts of the wing. For your swept foils, the tips will be loaded more heavily than the root. This is due to the downwash in the wake of the hydrofoil and how it affects the conditions along the span.

And the angle of attack of the foils will not be 2.25 degrees as indicated by the two-dimensional section data. Those data are for a foil of infinite span, so it produces an infintessimal downwash. The shorter the span, the greater the downwash to produce the same lift, so the angle of attack has to be increased to offset the downwash. Your foils have an aspect ratio of 4, and at a lift coefficient of 0.5349, an additional 2.44 degrees of angle of attack will be needed because of the downwash. So the incidence of your foils will be more like 4.7 degrees than the 2.25 given by the section data for the same lift coefficient.

But more than that, the downwash will increase the drag substantially. You should allow for an additional drag coefficient of 0.0228 because of the lift-induced drag. This is 0.21 pound of additional thrust required. The induced drag goes down by the square of the span, so if you make your foils wider they will be much more efficient. But this runs into problems of strength and stiffness, so the span is always a compromise. The induced drag goes DOWN with speed (squared), so flying at too slow a speed can actually require more power than going fast.”,”2005-08-05″,”Tom Speer”,”nopswd”,” “,”me@tspeer.com”,”2″

“36”,”872572″,”2″,”Re; Cheap ready made hydrofoils?||872572″,”Take a look at http://www.fastacraft.com/moulded_foils.html”,”2005-08-05″,”Tom Speer”,”nopswd”,” “,”me@tspeer.com”,”2″

“37”,”872569″,”2″,”Re; Question on fully submerged foils||872569″,”It’s not enough to balance lift against weight. You also have to balance the moments that want to turn the craft, tip it over, or pitch it. And the problem with balancing the lift is the lift is constantly changing as a function of speed, the attitude of the craft, and the disturbances from waves, gusts, thrust changes, etc. So when it does change, there has to be a means of returning it to its original value. If you hold a broom upside down on your hand, it’s easy to compensate for the weight of the broom. But the moments are unstable so you can’t maintain that balance without actively compensating for any change.

There’re also the problems of regulating the flying height, maneuvering and accommodating different amounts of payload.

Lift at a constant speed and attitude does drop off as the foils get close to the surface. It’s possible to use this effect to stabilize the craft if you are operating in flat water. But this also robs the fully submerged foil of much of its performance advantages.”,”2005-08-05″,”Tom Speer”,”nopswd”,” “,”me@tspeer.com”,”2″

“38”,”862463″,”2″,”Re; Cheap ready made hydrofoils?||862463″,”There were some articles published in the late 1950s – early 1960s in hobbyist magazines as to how to make wooden hydrofoils and add them to runabout-type boats. For example, Popular Science June 1960 has an article, “How I Fitted Oak Hydrofoils To My 14-Foot Runabout.” Science and Mechanics Feb 1960 has a similar article, with foil design for boats up to 18 feet length. Take a look at the magazine descriptions on the IHS website in the Hobbyist section of this page: www.foils.org/popmags.htm.

You can buy copies of old magazines by searching for them on eBay and/or google.com. Sooner or later, just about everything shows up on eBay. Google will find you magazine sellers who sell directly. I have used the Canadian company “Smelly Old Books” http://members.ebay.com/aboutme/sobooks/(contact: John Muxlow jj.muxlow@ns.sympatico.ca) to obtain reasonably priced copies of articles back to the 1920s and earlier (S.O.B. has an almost complete collection of Mechanix Illustrated, Popular Mechanics, and Popular Science). It has been a while since I contacted them, so I hope the URL and email address are still good.”,”2005-07-18″,”Barney C Black”,”nopswd”,” “,” “,”0”

“39”,”861182″,”2″,”Re; FOIL SHAPE AND ANGLE||861182″,”So No help or confirmation on the previous calculations?
“,”2005-07-15″,”Umi_Ryuzuki”,”nopswd”,” “,”umi_ryuzuki@hotmail.com”,”0″

“40”,”860748″,”2″,”Re; Question on fully submerged foils||860748″,”Maintaining a close enough balance between weight and lift without feedback control to allow a flight for more than a few seconds is currently not possible. Suggest you consider a mechanical feedback controller. The Rave, Hobie Trifoiler, and the height control on Talaria IV all use mechanical surface sensors with linkages to their foils to maintain a balance between lift and weight. “,”2005-07-14″,”Harry Larsen”,”nopswd”,” “,”htdr.larsen@verizon.net”,”0″

“41”,”860689″,”2″,”Re; Question on fully submerged foils||860689″,”Thanks! That puts me very close to the goal.

Andy”,”2005-07-14″,”Andy”,”nopswd”,” “,” “,”0”

“42”,”860646″,”2″,”Re; Question on fully submerged foils||860646″,”If you are using fully submerged foils for main lift, you can have a 25 to 35% lift stabilizing, surface piercing foils to supplant an autopilot. I do not know of any all fully submerged foil systems that are self stable.”,”2005-07-14″,”NAT KOBITZ”,”nopswd”,” “,”kobitzn@ctc.com”,”0″

“43”,”860356″,”2″,”Question on fully submerged foils||860356″,”I have read that fully submerged foils require flight control. My question is whether this is strictly necessary, or if I could design a submerged foil for a specific boat through experimentation that would be functional without flight control. The idea being to balance the lift against the weight of the boat.

Thanks,
Andy
“,”2005-07-13″,”Andy”,”nopswd”,” “,” “,”0”

“44”,”856862″,”2″,”Cheap ready made hydrofoils?||856862″,”Forgive me for my ignorance- I’m only just starting to embark on a project to add hydrofoils to a 12′ boat. I’ve been searcing for ready made aerofoil sections that could be used, and of course there are none specifically for hydrofoils-other than sailing ones, which are still expensive and probably unsuitable. When I searched under ‘aluminium aerofoil section extrusions’ I came up with extrusions intyended as sun blinds, see page 14 for an example :http://www.productselector.co.uk/docs/4/02274/external/COL02274.pdf
I realise the sections avaiable would not be the most efficient, but would using these extrusions provide a cheap and reasonably efficient way of getting foilborne?

Any comments?

Cheers, Roland

r.wilson@bath.ac.uk”,”2005-07-07″,”Roland Wilson”,”nopswd”,” “,”r.wilson@bath.ac.uk”,”0″

“45”,”855770″,”2″,”Re; Re; FOIL SHAPE AND ANGLE||855770″,”Let me see if I read all this correctly.

S = L / F U^2 Cl

S = 5lbs/ (2.09)(12©÷)(0.5349*) *assuming a 2.25¡æ angle of attack.

S = 5lbs/ 160.9835

S = 0.310591 sq ft

Therefore S = 44.725104 sq inches divide by 3 for each foil

Each wing needs an area of 14.908 sq inches
¡î14.908 = 3.861 square plate cut diagonally

Am I correct in assuming a six wings one on each side of the struts with

a root of 2.5″
trailing edge of 3.875″
tip length of 1.375″

Will fly a 5 lbs (2.268k) hydrofoil?
Would this include control surfaces, or would adding control surfaces to the existing area be preferred?

Thank you in advance.

Umi_Ryuzuki

Nyow
\
=^o^=

“,”2005-07-04″,”Umi_Ryuzuki”,”nopswd”,” “,”umi_ryuzuki@hotmail.com”,”0″

“46”,”830353″,”2″,”Re; Foil Design Help||830353″,”hi sam,

you might want to re-think the approach to what you are trying to achieve. a hydro foil solution for wake boards has been around for ages.
it’s called the WEDGE and is a fold down foil under the stern of the boat that pulls the boat DOWN at speed to increase the wake.

http://www.glencraftmarina.com/Pages/malibu.html

cheers
boogie”,”2005-05-17″,”Boogie”,”nopswd”,” “,” “,”0”

“47”,”824680″,”2″,”Foil Design Help||824680″,”Gday mate my name is sam doolan and I am an Industrial design student from
RMIT university Melbourne Australia. I am currently designing a foil, which
creates larger wakes for wakeborders by lifting the front of the boat and
transferring the weight to the back, to give it larger wakes. However I am
sure how the foils should be designed. Wether one at the front of the boat,
or coming off both sides or both. Would you be able to answer this question
for me.”,”2005-05-06″,”sam doolan”,”nopswd”,” “,”doolans@bigpond.net.au”,”0″

“48”,”824319″,”2″,”Re; Re; coordinated (banked) turns||824319″,”Could you send us a picture?”,”2005-05-06″,”Harry Larsen”,”nopswd”,” “,”htdr.larsen@verizon.net”,”0″

“49”,”823711″,”2″,”Re; Re; coordinated (banked) turns||823711″,”Thanks for your response and info. We call the boat “straightfastboat” as it’s very fast in a straight line, 65mph+ and requires slowing and greater immersion of the rudder to turn with a bit of inboard banking. I’ll try deepening the rudder as a first move and stay away from adjustable angle of attack in the foils. “,”2005-05-05″,”Mike Turner”,”nopswd”,” “,”mike@turnermarinegroup.com”,”0″

“50”,”823598″,”2″,”Re; Re; coordinated (banked) turns||823598″,”Roll can be a complicated consequence of rudder deflection. Since the rudder is located below the center of mass, a port deflection of an aft-mounted rudder will result in a rolling moment to port.

It also produces a yawing moment, of course, and as the craft yaws to port, it picks up a sideslip (leeway) angle. If the foil system has positive roll stability – like a V foil configuration – the sideslip angle will also make the craft roll to port. Roll due to sideslip is likely to be the more powerful effect of the two. As the bank develops, the sideslip angle will be reduced.

But it takes some time for the craft to rotate enough to generate the sideslip. So there’s lag between when you put in the input and when the rolling due to sideslip is experienced. The rolling moment due to the rudder deflection itself is prompt. The sideslip itself will reduce the force on the rudder, lessening the rolling moment from that source.

If the rudder is on a forward strut, then the craft will yaw in the opposite direction, the sideslip will be reversed, and the roll due to rudder deflection and the roll due to sideslip will be of opposite sign.

So the relationship between rudder and roll depends on the placement of the rudder, the stability of the craft, and the frequency of the input. The rolling due to rudder could be opposite in sign for different frequency ranges.
“,”2005-05-04″,”Tom Speer”,”nopswd”,” “,”me@tspeer.com”,”0″

“51”,”823592″,”2″,”Re; Re; coordinated (banked) turns||823592″,”Yes, typically. Like ailerons on an airplane wing.

But they could be done in many ways. You could change the incidence on a whole foil, positive for the port foil and negative for the starboard foil to get a positive rolling moment. You could articulate the outer panel of a hydrofoil. Flaps are an effective and easily mechanized way to go. But not the only way.

Aeronautical experience has shown that it’s not a good idea to try to produce roll from a canard (forward wing), however. The resulting downwash has the opposite effect on the aft wing and can cancel or even reverse the intended rolling moment. The effects could be even more complicated by the way hydrfoil downwash is affected by the free surface.”,”2005-05-04″,”Tom Speer”,”nopswd”,” “,”me@tspeer.com”,”0″

“52”,”821847″,”2″,”Re; Re; coordinated (banked) turns||821847″,”When you dig up the info on this I’d love to se it. I have a Volga 70 that I’d like to convert the banking in turns to inboard rather than that disconcerting outboard feeling. My rudder depth will be increased soon and I’ll report the result. It currently is as deep as the prop blade sweep. Anyone have anything to suggest? “,”2005-05-02″,”Mike Turner”,”nopswd”,” “,”mike@turnermarinegroup.com”,”0″

“53”,”821718″,”2″,”Re; Re; coordinated (banked) turns||821718″,”You mention ‘roll surfaces’… are those the main hydrofoil surfaces (or flaps on the main foil)?”,”2005-05-01″,”Wayne Johnson”,”nopswd”,” “,”tspwtj@yahoo.com”,”0″

“54”,”821713″,”2″,”Re; Re; coordinated (banked) turns||821713″,”The mechanical… I wanted to be sure that I was not missing a simple thing like ‘roll is a consequence of rudder’, or some other simple mechanical link.”,”2005-05-01″,”Wayne Johnson”,”nopswd”,” “,”tspwtj@yahoo.com”,”0″

“55”,”821318″,”2″,”Re; coordinated (banked) turns||821318″,”The definition of a coordinated turn is zero lateral acceleraion (along the Y axis). One way to achieve it is to use lateral acceleration feedback to a rudder. The rudder turns the craft about its Z axis to zero the leeway angle that results in the side force causing the acceleration.

However, a tricky aspect of this with a hydrofoil is the center of mass of the craft is well above the foils, and the crew station is typically above that. So you have an issue with how you enter the turn. If the craft rolls about the hydrofoils, there will be a significant lateral acceleration of the center of mass, and a somewhat greater acceleration yet at the crew station. Acceleration feedback at that point would turn the rudder to point the craft to the outside of the turn. So you’d have the roll control and the yaw control fighting each other, and when the two get out of phase you could lose control.

Everything will be fine for slow gentle entries that don’t develop much acceleration. But if you apply a frequency sweep to the wheel, sarting with a slow oscillation of the wheel and working up to faster and faster reversals, you will arrive at the point at which the motion becomes alarming. I had the chance to experience this when I rode on Harry Larsen’s Talaria.

A better approach would be to rotate the craft about either the center of mass or the crew station. This requires that the hydrofoils describe a pendulum motion, swinging to the outside of the turn as the craft rolls and the g-loads increase – keeping the net hydrodynamic force aligned with center plane at all times. To get such a motion probably requires a means of generating direct side force on the foils, such as both a forward and aft rudder or a flap on a main strut in addition to the rudder. An interconnect between the roll surfaces and the side force flap(s) would generate the right linear acceleration of the foils in concert with the roll acceleration. The feedbacks would then deal with the left-over motion due to imperfect match in the interconnect, and the fact that the control deflections you want initially are not necessarily proportional to what you want in the steady state.

An alternative approach is to use model following. The commands from the helm go to a dynamic model that has the ideal chaaracteristics – rolling about the crew station, etc. The ideal model produces state, rate, and acceleration commands to a feedback regulator control law that makes the hydrofoil follow the ideal motion as closely as possible. The regulator would typically be designed using multivariable control theory (Linear Quadratic Gaussian, Pole Placement, or many others).

The ideal model can be simulated separately, independent of the configuration of the hydrofoil itself, assuming perfect model following. This lets you tune the characteristics in parallel with designing the rest of the system. For example, you might want the ideal model to descend a bit at the same time that it kicks the hydrofoils to the outside of the turn so that the foil tips don’t broach because of the pendulum motion.

I recommend Thor Fossen’s books and papers for more details.”,”2005-04-30″,”Tom Speer”,”nopswd”,” “,”me@tspeer.com”,”0″

“56”,”821034″,”2″,”Re; coordinated (banked) turns||821034″,”From a roll acceleration point of view a coordinated turn is no different than flying straight and level. Is your question related to the mechanical, sensor, electronic, or mathematical means of performing a coordinated turn? “,”2005-04-30″,”Harry Larsen”,”nopswd”,” “,”htdr.larsen@verizon.net”,”0″

“57”,”819978″,”2″,”coordinated (banked) turns||819978″,”How do you get a fully submerged type hydrofoil to bank in a turn?
Are there any documents which explore the requirements of coordinated turning? “,”2005-04-28″,”Wayne Johnson”,”nopswd”,” “,”tspwtj@yahoo.com”,”0″

“58”,”795120″,”2″,”Re; Foil pressure coefficient data||795120″,”I think your best bet would be to go to something like a Navier Stokes CFD code if you really want to characterize the flow well past stall.

You might be able to get some idea by going as far as you can with an integral boundary layer code like XFOIL. The idea is separation occurs in an adverse pressure gradient. So there must be a lower pressure ahead of the separated flow that is attached, and that might be predictable with a lesser method. My guess – and it’s just a guess – is that even though you operate well past stall, the worst case as far as minimum pressure is concerned might be at or just past stall, and this could be computed with something like XFOIL.

If you application is operating near the surface, though, ventilation rather than cavitation is likely to be your real problem. They both end up with vapor on the suction side, but for completely different reasons. The separated flow will be a real bear when it comes to ventilation, because you are setting up all the necessary preconditions for ventilation. If you insist on the separation, you’ll have to concentrate on keeping the air away from the separated regions.”,”2005-03-12″,”Tom Speer”,”nopswd”,” “,”me@tspeer.com”,”0″

“59”,”788896″,”2″,”Re: Foil pressure coefficient data||788896″,”Is stalling a separation of the boundary layer? Probably, the shapes with negative presure gradients will be usefull for your purpose to avoid cavitation. See my message No 7888876 and attached file.

“,”2005-03-01″,”Ihor Nesteruk”,”nopswd”,” “,”inesteruk@yahoo.com”,”0″

“60”,”788876″,”2″,”Hydrofoils without cavitation||788876″,”I am looking for people or organization wich are interested in futher investigation and wind tunnel tests of hydrofoils without cavitation. Please find the
details below and in the attached file.

Dr. Ihor Nesteruk
Institute of Hydromechanics
National Academy of Sciences of Ukraine
Kyiv
——–
Axisymmetric and plane shapes with negative pressure
gradients at a surface are calculated. It is shown
that the length of the pressure increase zone may be
very short. Some shapes of axisymmetric bodies tested
in a wind tunnel provide unseparated flow patterns.
Such shapes are both of theoretical and practical
interest, since the unseparated flow pattern gives an
opportunity to reduce the total drag of vehicles
moving in gas or liquid. Moreover presented shapes
probably provide no cavitation at arbitrary small
cavitation numbers (see theoretical and experimental
arguments in [1,2]). Tests in a water tunnel have to
be carried out to prove this fact. For the presented
2D profiles, there were no wind tunnel tests to
investigate their separation behavior at different
angles of attack. Such experiments could be carried
out in the wind tunnel of Kyiv Institute of
Hydromechanics. [1] Nesteruk I.: Can Shapes with
Negative Pressure Gradients Prevent Cavitation. 4th
ASME/JSME Joint Fluids Engineering Conference,
Honolulu, USA, July 2003: FEDSM2003-45323.[2]
Takahashi S., Washio S., Uemura K., Okazaki A.:
Experimental study on cavitation starting at and flow
characteristics close to the point of separation.
Fifth Symposium on Cavitation: No. Cav03-OS-3-003, 2003.

“,”2005-03-01″,”Ihor Nesteruk”,”nopswd”,” “,”inesteruk@yahoo.com”,”0″

“61”,”787296″,”2″,”Foil pressure coefficient data||787296″,”Could anyone tell me how I could get hold of minimum pressure coefficient data for aerofoils operating at and beyond the stall (ideally up to twice the stalling incidence)? I am designing a lifting device for a marine application which is heavily stalled for much of its operating life, and must not cavitate.

Many Thanks

Chris Huxley-Reynard

chris_huxley_reynard@hotmail.co.uk”,”2005-02-25″,”Chris Huxley-Reynard”,”nopswd”,” “,”chris_huxley_reynard@hotmail.co.uk”,”0″

“62”,”779156″,”2″,”Lift formula||779156″,”Konstatin Matveev’s lift formula is encoded in Excel on this web site:
http://mysite.verizon.net/res6pe7p/

“,”2005-02-10″,”Harry Larsen”,”nopswd”,” “,” “,”0”

“63”,”776265″,”2″,”Calculating Lift||776265″,”Sorry but I’m not too good at math. Can somebody please give me a simple equation that will allow me to calculate approximate lifting force in kg (what the hell is a newton anyhow ?) at a given area (sq meter) speed (kph) and angle of attack (I want to experiment with variable angles to load or unload a vessel). Now I know that aspect ratio, foil thickness, diehedral etc etc all play a part but I just want approximate values please. “,”2005-02-05″,”Andy”,”nopswd”,” “,”formula@bigpond.net.au”,”0″

“64”,”764798″,”2″,”Re: FOIL SHAPE AND ANGLE||764798″,”It’s achievable. You’ll probably need a foil with a chord of about 750mm. At the speeds you’re talking about, just about any decent airfoil section would work. The incidence of the foil needs to be set with its zero lift lne about 5 – 7 degrees above the trim attitude of the boat. If you build it so you can bend the trailing edge up or down, that will allow you to fine tune the lift.”,”2005-01-15″,”Tom Speer”,”nopswd”,” “,”me@tspeer.com”,”0″

“65”,”759759″,”2″,”Re: Foil Surfing||759759″,”there is no foil surfing allowed anymore.

You must shape your own board out of koa and paddle it – no more tow in’s mish”,”2005-01-05″,”big wave surfer”,”nopswd”,” “,”bigwavesurfer”,”0″

“66”,”756659″,”2″,”Foil shape and size||756659″,”Many thanks for your reply to my request for info on foil design,
being an absolute bunny in this area everything Ican learn is a huge benefit.
Iam hoping to achive a slightly ‘better’shape than a circle cord, I have a copy of the shape of a Speer H005 foil and am aiming at that shape if it will improve lift on the cord.
I note that the C/L increases somewhat at higher angles of attack is there some reason for not using 6,8 or 10 degree angles of attack?
Is there a minimium depth that the foil should be below the surface when travelling at speed, being a catamaran we dont draw much but I can extend the foil down by using longer end plates if required.
Once again many thanks for your time, I’ll keep you posted with the results when they occur.
Regards John”,”2004-12-28″,”JOHN PAYNE”,”nopswd”,” “,”gateopen@xtra.co.nz”,”0″

“67”,”756181″,”2″,”Re: FOIL SHAPE AND ANGLE||756181″,”John,

I see that the table I provided you is unreadable. It may help if you know that the first line and the first column is Angle of attack = -4.00, second column is Coefficient of lift = .0065, third column is Coefficient of drag = .0309, forth column is Coefficient of Moment = -0.1053, and the fifth column is lift over drag ratio = .210. Hopefully, with this you can read the table.

“,”2004-12-27″,”Ray Vellinga”,”nopswd”,” “,”rvell@san.rr.com”,”0″

“68”,”756177″,”2″,”Re: FOIL SHAPE AND ANGLE||756177″,”Hello, John,

Here is a little cook-book on designing hydrofoil wings. As a welder, you may find the “ogival” AKA
Plano-convex shape easiest to fabricate out of aluminum, steel or stainless steel. The wing is created
by twice cutting a pipe lengthwise to form a vault-shaped piece. On the bottom inside weld a flat plate.
Use a grinder to make your welds fair. Fill in the pits with Bondo. Make everything smooth.
You may choose to round off the leading edge to avoid slicing marine life as you fly by.
The trailing edge should be sharp, but not so sharp as to be hazardous.
You then have a wing, the top of which is a segment of a circle with the underside flat.
For starters, make the thickness to cord ratio 10%.

You need to estimate the area needed, so get out your calculator. The formula is:

S = L / F U^2 Cl

S = Surface area in Square feet
L = Lift (this is the total weight of your boat, crew, etc., in Pounds)
/ = “divided by”
F = Factor to adjust for water density, unit measurements, etc. Use the number F = 2.09
U^2 = Velocity in MPH multipied by itself (squared)
Cl = Coefficient of lift. See the table provided below for Cl. You should cruise at a high L / D or say 2.25degrees.
Take off will be at a higher Cl & lower speed. You must make some assumptions based on experience.

I hope you didn’t sleep through math class.
Contact me if you have problems: rvell@san.rr.com

Ray Vellinga

Water Tunnel Observations on the Flow Past a Plano-Convex Hydrofoil By R B Wade Feb 1964
Caifornia Institute of Technology

Graph the Characteristics of Hydrofoil in Non-cavitationg Flow, Table, Page 51

v = 31.32 ft/sec = 21.35 M/H
Re = 0.75 X 10^6

Angle Coefficient Coefficient Coefficient L / D
of of Lift of Drag of Moment ratio
Attack
Series 1 Series 2 Series 3

-4.00 0.0065 0.0309 -0.1053 0.210
-3.50 0.0487 0.0262 -0.0932 1.859
-3.00 0.0995 0.0223 -0.0782 4.462
-2.75 0.1247 0.0201 -0.0723 6.204
-2.50 0.1481 0.0190 -0.0665 7.795
-2.25 0.1721 0.0178 -0.0564 9.669
-2.00 0.1921 0.0164 -0.0476 11.713
-1.75 0.2140 0.0152 -0.0400 14.079
-1.50 0.2420 0.0149 -0.0375 16.242
-1.25 0.2636 0.0146 -0.0313 18.055
-1.00 0.2778 0.0136 -0.0244 20.426
-0.75 0.3106 0.0137 -0.0192 22.672
-0.50 0.3295 0.0131 -0.0140 25.153
-0.25 0.3583 0.0133 -0.0089 26.940
0.00 0.3714 0.0129 -0.0026 28.791
0.25 0.4023 0.0122 0.0016 32.975
0.50 0.4261 0.0119 0.0089 35.807
0.75 0.4478 0.0126 0.0148 35.540
1.00 0.4539 0.0138 0.0197 32.891
1.25 0.4490 0.0141 0.0245 31.844
1.50 0.4644 0.0152 0.0303 30.553
1.75 0.4781 0.0164 0.0356 29.152
2.00 0.5031 0.0164 0.0408 30.677
2.25 0.5349 0.0167 0.0474 32.030
2.50 0.5443 0.0172 0.0540 31.645
2.75 0.5725 0.0185 0.0593 30.946
3.00 0.5797 0.0184 0.0647 31.505
3.50 0.6360 0.0217 0.0775 29.309
4.00 0.6751 0.0245 0.0896 27.555
5.00 0.7732 0.0338 0.1151 22.876
6.00 0.8352 0.0447 0.1391 18.685
8.00 0.9873 0.0735 0.1858 13.433
10.00 1.0919 0.1182 0.2044 9.238
“,”2004-12-27″,”Ray Vellinga”,”nopswd”,” “,”rvell@san.rr.com”,”0″

“69”,”754783″,”2″,”Re: Foil Surfing||754783″,”I believe you need to really think about your design expectations. In the application you are considering, manueverablilty and stability are inherently opposite. If the board is stable, such as with surface peircing foils, you won’t have the manueverability of a board such as the ones based on an “Air Chair” or “Sky Ski”. You are going to eventually have to decide where to make the trade-off.”,”2004-12-22″,”Scott Smith”,”nopswd”,” “,”ssmith@veinrxinc.com”,”0″

“70”,”753679″,”2″,”FOIL SHAPE AND ANGLE||753679″,”I HAVE A 10 TON STEEL CATAMARAN HOUSE BOAT WITH 2 X 90 HP OUTBOARDS
THAT SUFFERS FROM A HUGE BOW WAVE COMING OVER THE FORE DECK AT SPEED
MAX SPEED BEING ABOUT 12 KNOTS DUE TO HALF A TON OF WATER ON THE BOW.
I WOULD LIKE TO ADD A FOIL BETWEEN THE HULLS AT THE BOW TO LIFT IT ABOVE THE BOW WAVE SITUATION. CAN YOU SUGGEST A FOIL SHAPE OR SITE THAT A SIMPLE PERSON CAN UNDERSTAND TO FIND A SHAPE WITH CLEAR INSTRUCTIONS AS TO WIDTH AND THICKNESS OF FOILS AND AN ESTIMATED LIFT IN LBS/SQ IN ON THE FOIL. I HAVE A 1200MM GAP BETWEEN THE HULLS AND FIGURE THAT I NEED ABOUT 2-3000 LBS LIFT IS THIS ACHIVEABLE, THE FOIL CAN BE AS LONG AS REQD AS THE BOAT IS 12M LONG.IM VERY HANDY WITH THE MIG WELDER IN THE GARAGE BUT CANNOT TRANSLATE THE INFO ON FOIL DESIGN SITES INTO A SIMPLE WELDABLE SHAPE THAT MAY WORK, ANY HELP WOULD BE APPRECIATED
JOHN”,”2004-12-19″,”JOHN PAYNE”,”nopswd”,” “,”gateopen@xtra.co.nz”,”0″

“71”,”743418″,”2″,”Re: Foil Surfing||743418″,”For your wakeboard, if you want an alternative to the inverted “T” fully submerged hydrofoil designs used on hydrofoil surfboards and sailboards today, you could consider using an arrangement of surface piercing foils… these would be self-stabilizing. Back in 1978, an individual named Michael Shannon of Birmingham MI sent a letter to Dave Keiper, who was offering foils kits for Hobie Cats. He stated that he and his partner James Coulter had successfully adapted parts from Keiper’s foil kit to a windsurfer and planned to make a production run. In connection with this correspondence, Keiper sketched and annotated his own first thoughts on how he would do the design. Unfortunately, Keiper is deceased, and the return address on Shannon’s letter no longer exists, according to the USPS database. So I don’t know if this hydrofoil windsurfer ever went into production or not. Anyway, I put a copy of Keiper’s notes and the Shannon letter up on the web at http://www.exigent.info/DAK-Windsurf.pdf. So take a look. It was common practice for the pioneering hydrofoil designers starting with Alexander Graham Bell to try out their hull/foil prototypes by towing them, so this is similar to a wakeboard being towed by motorboat, only the towed board is the end product rather than an interim test piece. Hopefully this info is of some help. Maybe someone else who checks the IHS BBS will know something of Shannon and Coulter. As to sources of foils and struts, that is another subject, but there are some: mostly in connection with human-powered vehicles, but also a company that makes them for adding to Moth class sailboats.”,”2004-11-24″,”Barney C Black”,”poopdeck”,” “,”barney@alum.mit.edu”,”0″

“72”,”742586″,”2″,”Re: Foil Surfing||742586″,”Hi Mitch,

In a first time, I think the better solution is a very simple inverted T foil on the rear (about under the rear foot) and a surface traking “patin” on the front. The rear foil must be about 0.1 square meter area.

For the front “canard” there are several solutions :

The more simple is a planing surface but you can try too somes V surface piercing foils.

Gérard”,”2004-11-23″,”Gérard Delerm”,”nopswd”,” “,”gerard.delerm@free.fr”,”0″

“73”,”742553″,”2″,”Foil Surfing||742553″,”I am interested in alternate designs for foil boarding waves. Currently many surfers are using a foil like the water ski chair type with a stand up board similar to a snow board. It seems to me that there might be a more stable and/or manuverable design like some of the boat foils I have seen. The speeds are 15-30 mph and generally the weight of a surfer(180lbs). Manuverability and stability is a must. Can you make some suggestions as to designers that might help me or direct me as to how to decide on a design and type of foil for surf? “,”2004-11-23″,”Mitch Haynie”,”surfer”,” “,”haynie240@msn.com”,”0″

“74”,”730516″,”2″,”Re: Advanced Educational Pages||730516″,”Hi Barry,

If you try to do any Educational Pages project I can try to translate in French (in IHS there is “International” )
I am not a professional translator but I think I can make good translations if I can have “chat” with the author.

Gerard
“,”2004-10-30″,”Gerard Delerm”,”nopswd”,” “,”gerard.delerm@free.fr”,”0″

“75”,”730318″,”2″,”Re: Advanced Educational Pages||730318″,”An excellent suggestion. The closest the site has come is grouping correspondence by topic in the archives. Main page for accessing the master archives is //archive.foils.org/posted.htm.

There is also the barest start of an FAQ page at //archive.foils.org/faq.htm. However, no significant work was ever done on this.

As it states on the main page, the content of the IHS site reflects the interests of the members and visitors to the site who are willing to provide content. The site is very simple in design, no frames or anything, but rather sprawling. It is quite possible for someone with a particular interest or with a particular project in mind to assume responsibility for a page or pages on the site, whether the page currently exists or not, as an assistant to the webmaster. Revision and creation of pages is fairly simple with any WYSIWYG webpage creation program. File upload is easy with any FTP program such as CuteFTP. So if you were willing to undertake the project you suggest, even if it is over a considerable period of time, that is welcome, I believe, and fairly easily arranged.”,”2004-10-29″,”Barney C Black”,”poopdeck”,” “,”barney@alum.mit.edu”,”0″

“76”,”730307″,”2″,”Advanced Educational Pages||730307″,”I found Tom Speer’s discussion on foil stability facinating. I’ve not see this information explained so clearly before. Similarly, I’ve read explanations on calculating foil sizes from Tom and others which made it understandable for someone who hasn’t been in the industry for 30 years. I’ve seen so many of the questions I’ve asked years ago posted again and again.

Is there any way that somehow this explanation might be incorporated in an Advanced Educational page on the site? Perhaps as a continuation of the existing educational pages? I’ve gotten some great explanations from Tom, Mark Daskovsky, William O’Neill and Harry Larson.

I don’t know if you have a hit counter on your basic educational pages, but I know I’ve been there many times and they have been very very valuable. I don’t know how I could help, but I’d be happy to try.

Topics might be:

What shape foils? Typical NACA numbers (other better foils), what they mean and where to find the plots. The choices for submerged vs surface piercing vs strut foils.

How Big? Calculations on lift vs speed… or just a table. Wing loading.

Stability? Tom’s stability discusson, formatted would be great.

Takeoff speed vs flying speed, relationship between these and parameters in determining them.

Estimating power requirements or max speed foilborne…

Add to the glossary words and terms which are used a lot on the discussions: freude numbers, sea states … similar things which took a while to pull together.”,”2004-10-29″,”Barry Steele”,”nopswd”,” “,”barry_steele@yahoo.com”,”0″

“77”,”729123″,”2″,”Re: Foil Spacing||729123″,”Sumi raises an interesting point. PLAINVIEW never lost directional stability. One of the closest we probably came was when one of the main foil incidence angle control systems experienced a structural failure while foilborne. The result was that the foil with the failed system went to full-leading-edge-down. In response to the ship beginning to drop, the control system called for full foil-leading-edge-up. This resulted in one forward foil full leading edge up and the other forward foil full leading edge down while foilborne. The helmsman chopped the throttle immediately. The ship rolled and the hull hit the water at foilborne speed at an angle of 18 degrees. After impacting the water, the ship continued to roll to 32 degrees before coming to a stop. No one was hurt and there was no damage to the ship. We continued back to port hullborne.”,”2004-10-27″,”Phil Yarnall”,”poopdeck”,” “,”YarnallP@nswccd.navy.mil”,”0″

“78”,”729122″,”2″,”Re: Foil Spacing||729122″,”John, By conventional configuration, I refer to the airplane configuration. On PLAINVIEW, we showed the model test results done at the Michigan tank showing the loss of directional control to each of the skippers assigned. One could argue that the carriage helped the ship roll over, but it would still be quite a ride. I know of no instance where we actually encountered this situation since the crew was attuned to the possibilities.”,”2004-10-27″,”S. Arima”,”poopdeck”,” “,”sumi@foils.org”,”0″

“79”,”729121″,”2″,”Re: Foil Spacing||729121″,”Hi Sumi, By “Conventional” configuration, do you mean “airplane” configuration where the aft foil is lightly loaded, as was in the case of Plainview? I understand there was an incident where the stern tried to replace the bow in the foilborne mode, if you know what I mean.
“,”2004-10-27″,”John Meyer”,”poopdeck”,” “,”editor@foils.org”,”0″

“80”,”729120″,”2″,”Re: Foil Spacing||729120″,”I would like to add a word of caution to Tom’s extensive and informative dissertation. The location of the struts on the hull, especially in the conventional configuration, one needs to look at the sea state and hull contact with the sea. In a quartering sea, where the bow of the ship could make contact with the wave could produce side loads that could easily overcome the ability of the aft strut to maintain directional control. Stability needs to be looked at in more than just the foilborne situation.”,”2004-10-27″,”S. Arima”,”poopdeck”,” “,”sumi@foils.org”,”0″

“81”,”729119″,”2″,”Re: Foil Spacing||729119″,”Phil, You may also recall that during detail design and construction of PLAINVIEW, it became apparent that the initial location of one of the diesel generators was too far forward and that the aft foil would have been too lightly loaded and subject to broaching, so the generator was moved aft by at least one frame space.”,”2004-10-27″,”Mark Bebar”,”poopdeck”,” “,”mbebar@csc.com”,”0″

“82”,”729118″,”2″,”Re: Foil Spacing||729118″,”On PLAINVIEW, the concern was not so much the space between the forward and aft foil, but rather the amount of lift capacity in the forward and aft foils. 90% of the lift capacity was in the forward foils and 10% of the lift capacity in the aft foil. Knowing the precise longitudinal center of gravity became a high concern. Ultimately, there was scale at the ramp to the ship. The weight and location of each new piece of equipment and gear was recorded when it came onboard and the LCG calculated. There was volume in the aft portion of the hull which was unusable for payload due to the requirement to maintain 90% of the load on the forward foils.”,”2004-10-27″,”Phil Yarnall”,”poopdeck”,” “,”YarnallP@nswccd.navy.mil”,”0″

“83”,”729117″,”2″,” Stability Has Been Investigated||729117″,” Yes, stability has been extensively investigated. The Hydronautics handbook on IHS’s AMV CD#1 has a whole chapter devoted to trim and a whole chapter devoted to longitudinal stability. You can also find papers on hydrofoil stability on the NACA technical reports server (http://naca.larc.nasa.gov/).

There are also performance aspects to hydrofoil spacing. Constantin Matveev used to have a page on his web site that showed how the rear foil should be located in the rising part of the transverse wave generated by the forward foil. This leads to a foil spacing based on the design Froude number.

With regard to “stability”, the foil spacing is just one of many important factors. I’d say there are really four areas to consider in addition to wave drag, all of which are affected by foil placement and spacing. The first is trim – the ability achieve an equilibrium where all the forces and moments balance (sum up to zero). For best performance, the least drag is obtained by the “airplane” configuration, with a large foil taking nearly all of the weight of the craft and a lightly loaded (quite possibly negatively loaded) stern foil for stability and trim. This means the main foil must be placed in the vicinity of the center of gravity, which for most boats is a little aft of midships. This only leaves half the length for foil spacing. If you look at the Carl hydrofoil, you’ll see that the hull has a slender tail to put the stern foil farther aft while keeping the weight near the main foils.

Then there’s stability itself. Stability has to do with whether the craft returns to a condition of equilibrium after having been disturbed from an initial equilibrium. So stability presupposes trim – it’s meaningless otherwise. Stability is usually further broken down into static stability, which is the instantaneous tendency to return to trim after a disturbance, and dynamic stability which deals with whether or not the motion damps out over time. The pitch damping goes by the square of the distance between the foils and the center of gravity. So there’s a definite connection between stability and foil spacing there. Heave damping is usually quite high by the nature of hydrofoils, so if the pitch heave coupling is stable, the dynamic heave stability will probably be stable.

The static stability in the longitudinal axis depends on how the moments change for a disturbance in pitch angle at constant depth, and how the moments change with depth at a constant pitch attitude. A bow-up change in pitch must generate a bow-down change in the pitching moment. As a practical matter, this requires that the forward foil be more heavily loaded – it must carry more of the boat’s weight per unit area than the aft foil. So as you change the foil spacing and placement relative to the center of gravity, you have to change the area of the foils. An increase in height (decrease in depth) must also generate a bow-down pitching moment to have stable pitch-heave coupling. This is why you see inverted T foils used so extensively for the aft foil and either surface piercing foils or flapped foils forward. Again, the spacing and placement of the foils is very important, taking into account their heave stiffness.

Yaw damping also improves with the square of the distance between the foils and the center of gravity. So there’s another effect of foil spacing. Roll damping goes by the square of the foil span, so it’s not very affected by longitudinal spacing, although it’s heavily influenced by the lateral spacing of the foils.

The next issue to consider is controllability. Control power is needed to achieve the desired trim state. Especially with surface piercing foils, there will be an optimum flying height for best performance, and the pitch attitude must be trimmed so as to achieve it. Control power is needed for stabilization if you are actively augmenting the craft’s stability, as is universally done for fully submerged foil systems. Control is also needed for maneuvering. Finally, control power may be needed for achieving the desired ride quality, as in using direct lift to counter the effects of waves. If you have a system with high static stability, you need to have more control power for trim. If you have a system that is unstable, you need more control power than a neutrally stable craft.

Once again, hydrofoil spacing comes into account because it provides the moment arm for a given change in force at the foil. If you want to generate a direct force at the center of gravity, this will require more or less control from other foils to cancel out the moments if the foil is located away from the center of gravity. If you want to generate a moment but the foil is close to the c.g., it’s like mounting a door knob near the hingeline of a door – pushing or pulling on the knob will not rotate the door. So you have to consider the foil placement with regard to what controls you intend to associate with it.

Finally, there’s the issue of ride quality. In the longitudinal plane, the hydrofoil can either platform the waves, flying at a constant elevation with respect to the earth; or it can contour the waves, flying at a constant distance above the water surface and following the wave shape. If you’re platforming, foil spacing may not be that important. Platforming requires a lot of direct lift control power, though, and the size of the wave you can platform at a given speed may be more limited by the control power than the flying height. But if you’re contouring, then the craft will be maneuvering much more aggressively in pitch, and the foil spacing issues above come into play. No hydrofoil on the ocean does exclusively one or the other. Wave heights greater than the flying height have to be contoured. And the short wavelengths have to be platformed.

In the lateral-directional axes, ride quality may dictate how the vessel rolls into and out of a turn, if it rolls at all. Hydrofoils have their center of mass well above the foils. If they do a skidding turn in a upright attitude, there’s an overturning moment toward the outside of the turn that has to be resisted. If they bank into the turn, then they have to roll first, then yaw as they carve the turn, and finally roll out. The rolling in and out of the turn causes lateral accelerations at the crew station that can be very disconcerting. The craft may actually have to apply direct side force to the foils while rolling so as to put the center of rotation near the center of gravity instead of at the foils. So there has to be a coordinated combination of rolling moment, yawing moment, side force, and lift to obtain acceptable lateral ride quality in maneuvers. Foil spacing would be a part of that equation, along with many other factors.

For example, an aft rudder will tend to produce side force to the outside of the turn, whereas a forward rudder would produce side force to the inside of the turn. It might be necessary to apply opposite forward rudder for a rapid change in aft rudder to generate the necessary side force while rolling, then wash out the forward rudder to allow the turn to develop. Depending on how sophisticated the control system is, the foil spacing may be important to tuning the interrelationship between the various forces and moments.

In most papers on hydrofoil stability, you will find equations that have a number of parameters called stability derivatives. They will describe how each derivative affects the craft’s stability and trim. But what you’ll find very difficult is coming up with good numbers for the stability derivatives to represent a given design. Getting those numbers is why companies spend so much money on testing and engineering analysis.

I hope this has given you the pointer you need. I think the Hydronautics handbook, “Hydrodynamics of Hydrofoil Craft”, is the most comprehensive source on the subject. If you can find them, there are two Hydronautics companion volumes, “The Stability Derivatives of a Hydrofoil Boat, Part I (and Part II)” that deal with estimating the numbers you need to actually calcuate the stability of a given configuration.
“,”2004-10-27″,”Tom Speer”,”poopdeck”,” “,”me@tspeer.com”,”0″

“84”,”729116″,”2″,”Foil Spacing||729116″,”Does anyone know of anything that has been published on the fore-and-aft spacing between the main foils and the stabilizer as related principally to pitch stability? I have searched the IHS CD-ROMs (lists of titles and abstracts of those that were at all promising), and have looked through my own file of hydrofoil material (mostly of Grumman origin), and have found nothing. Has this ever been investigated? Or has the spacing of the foils which falls out from the proportions of the hull always provided sufficient pitch stability, and the question has never come up? I want only to be pointed in the right direction; not to have any research done.
Is this question worth answering? I don’t know.

“,”2004-10-27″,”Joe Koelbel”,”nopswd”,” “,”JOEKOELBEL@aol.com”,”0″

“85”,”729115″,”2″,”Re: HYDROFOIL PONTOON||729115″,”Hi Ed. This same question has been asked of IHS several times over the years. Correspondence on the subject is archived on the IHS site at www.foils.org/motofoil.htm. I have yet to see a report or photo of a hydrofoil pontoon boat project completed and working. You should review this information. In particular, Charlie Pieroth’s recollection of his work at Dynamic Development, Inc. should be of interest.”,”2004-10-27″,”Barney C Black”,”poopdeck”,” “,”barney@alum.mit.edu”,”0″

“86”,”725016″,”2″,”Re: HYDROFOIL PONTOON||725016″,”To review the photos as described above go to http://www.totalrisk.com/diveboat.zip and copy Ed
“,”2004-10-18″,”Ed DeMoss”,”11030h”,” “,”eldemoss@totalrisk.com”,”0″

“87”,”725012″,”2″,”Re: HYDROFOIL PONTOON||725012″,”To review the photos as described above go to http://www.totalrisk.com/diveboat.zip and copy Ed
“,”2004-10-18″,”Ed DeMoss”,”11030h”,” “,”eldemoss@totalrisk.com”,”0″

“88”,”724962″,”2″,”HYDROFOIL PONTOON||724962″,” This is my first attempt to acquire information about putting a hydrofoil system under a pontoon boat. We have a 28 Ft. tritoon pontoon boat that has been built by our volunteer rescue dive group. The photos will best describe what it looks like. It is powered by a new Mercruiser Bravo 5.7 I/O with a ProCharger. It has 400 HP and runs right at 40 mph (via gps). It weights right at 6000 lbs. with dive tanks, equipment, and fuel. Planes very quickly.
There is a hydraulic lift on the front that extends 1 1/2 ft into the water on the front end that will lift well over 1500 lbs. The lift is for raising injured persons out of the water and for divers to get out quickly.
I weld aluminum as a hobby and have built and designed the entire system. We have an idea on how to do it but we need some advice and maybe some calculations. WE cover a very large lake and think this would be faster to respond to a accident. We have cad drawings on what exists.
2 questions am I asking the right group and is their anyone that can help? Thanks Ed DeMoss “,”2004-10-18″,”Ed DeMoss”,”nopswd”,” “,”eldemoss@totalrisk.com”,”0″

“89”,”716776″,”2″,”Power Boat Foil Design||716776″,”I am doing some research and feasibility studies on developing surface piercing hydrofoils for a power boat in the 24-30 foot range. I have read up a little on the Talaria as well as pulled the patent documentation on one of the kits they made for the boats back in the seventies. I have a couple of basic questions for the group here. First, when calculating the lifting force of a surface piercing foil is the lifting force of the foil roughly equal to that of a fully submerged foil of the same width as the part of the foil that is under water? Also what NACA foil profiles do people reccommend? The 16-510 design Tom Lang used? I tried plotting this shape out using one of the foil programs and the foil bottom was concave. Is this right or did I mess something up? Thanks for all the help in advance. I’m sorry if some of this is a little simplistic!”,”2004-09-30″,”Jim Harrington”,”nopswd”,” “,”jharrin1@msn.com”,”0″

“90”,”716553″,”2″,”Hydrofoil kitesurfer||716553″,”Has anyone seen a kitesurfer hydrofoil made of glass/kevlar/carbon fiber instead of the usual and heavy steel?

I am interested in building my own but steel is ruled out due to weight.

Thxs

Rod”,”2004-09-30″,”Rod”,”rodrigo”,” “,”rod.vr@teleline.es”,”0″

“91”,”716442″,”2″,”Re: Looking for Scott Smith||716442″,”Look no farther, you’ve found him again! I can still be reached at ssmith@syntheon.com. Missed you Diane. Sorry Tori and Todd, been under the weather and out of touch for a few months, but I’m coming back around. For any Dynafoil enthusiasts out there, I’m cleaning out the extra projects and thinking about selling a pair of mine (4 is just too many). I’ll post it here when I get my act together again. By the way, if any of you have a Honda PWC and wondered what would happen if you ignored the warning label and engaged the reversing lever while under way, here is the video. It is almost 3 meg, so if IHS decides not to post it, e-mail me and I’ll send it to you.”,”2004-09-30″,”Scott Smith”,”nopswd”,” “,”ssmith@syntheon.com”,”0″

“92”,”715374″,”2″,”Check the Dynafoil area||715374″,”Hi Diane,
Check out the Dynafoil threads that he and I were posting on. Here’s one address that’s listed: ssmith@syntheon.com

I’m not sure if it’s good though, and I had the same fatal crash a few weeks ago and lost his other address too.
Todd”,”2004-09-28″,”Todd Miller”,”nopswd”,” “,”austinado16@cs.com”,”0″

“93”,”714505″,”2″,”Looking for Scott Smith||714505″,”I am looking for Scott Smith from Florida. My computer crashed a few months ago and I lost his e-mail address. “,”2004-09-26″,”Diane Bell”,”nopswd”,” “,”outlawbettybel@hotmail.com”,”0″

“94”,”701771″,”2″,”Re: foilboard design||701771″,”Sam,
The choice of aluminium or carbon fibre on a foam core would be a decision you need to make based on what you are most comfortable working with. Either material should in principle be strong enough for this purpose (provided your carbon skins used over the foam core are thick enough). One of the tricky bits for either construction material would be to work out how you would connect the foil to its support strut. I assume you are working on using an inverted “T” shape foil and strut? If you are able to weld aluminium or can get someone to do that for you after you make the parts, that may prove to give the best connection at the junction of the T. For carbon fibre, making a sufficiently strong junction will take a bit more design and construction effort so that it does not simply fail at that point when you do more harsh manoeuvres with the board. “,”2004-08-30″,”Martin Grimm”,”nopswd”,” “,”seaflite@alphalink.com.au”,”0″

“95”,”697278″,”2″,”Re; foilboard design||697278″,”I suggest you take a look at Rich Miller´s article on hydrofoil sailboards. Go to: http://www.exigent.info/miller.pdf. You can also contact him directly for advice. I do not believe that he monitors this BBS.”,”2004-08-20″,”Barney C Black”,”poopdeck”,” “,”bcblack@erols.com”,”0″

“96”,”693486″,”2″,”foilboard design||693486″,”I am a kitesurfer and wakeboarder from England. I amm thinking of making a foil to go on the bottom of a board I have made. It would be for use at speeds of up to 20knts. I weigh about 13st, and my board is about 125cm long. I wouls be very keen to get some advice on foil design and building. Although I had been planning to make the foil from foam and carbon, I know that most production foils are aluminium. Why is this, and which is better to use. I have very little experience of hydrodynamics, but am keenm to learn. Many thanks, S.”,”2004-08-12″,”Sambo”,”nopswd”,” “,”sam.evans@students.pms.ac.uk”,”0″

“97”,”692405″,”2″,”Re; Re; Attitude control system||692405″,”Walt,

1. The text book “Theory of Wing Sections” by I.H Abbott & A.E. von Doenhoff provides geometry definition of various NACA profiles.

2. NACA foil sections are appropriate for underwater use. The main difference between air and water is the density of the fluid, that is easy to account for, see elsewhere on our website for information. Another issue is cavitation. This may not be a problem if your application is for relatively slow towing speeds.

3. The center of lift of foil sections is typically a quarter of the chord chord length aft of the leading edge. It remains at a relatively constant position for small variations in angle of attack.

4. Another package you could consider using is Wing Analysis Plus by Hanley Innovations (http://www.hanleyinnovations.com). This would help with answering many of the above issues.”,”2004-08-10″,”Martin Grimm”,”nopswd”,” “,”seaflite@alphalink.com.au”,”0″

“98”,”688064″,”2″,”Re; Re; Attitude control system||688064″,”Tom, thanks for the link. I’ll take a look.”,”2004-08-01″,”Walt Allensworth”,”nopswd”,” “,”walt@aharinc.com”,”0″

“99”,”687887″,”2″,”Re; Attitude control system||687887″,”//raphael.mit.edu/xfoil/”,”2004-08-01″,”Tom Speer”,”nopswd”,” “,”me@tspeer.com”,”0″

“100”,”685359″,”2″,”Attitude control system||685359″,”Hi! I’m building an underwater attitude control system that is to keep a towed device nearly horizontal. This system will include two movable underwater foils of modest size and force (under 100lb). The angle of attack of the foils will be controlled by weights. Is there a program I can use to generate [X,Y] pairs of points that describe common hydrofoil cross-sections? Are NACA foil sections appropriate for underwater use? Also… knowing the exact center of lift of the foil section is a critical aspect of the design. Are there programs that identify the center of lift of common foil sections?

Thanks in advance!”,”2004-07-27″,”Walt Allensworth”,”nopswd”,” “,”walt@aharinc.com”,”0″

Re; Re; How foils lift

[Date/Time=05-26-2003 – 11:11 PM]

Name:Ian Ward ianward@ozemail.com.au, [Msgid=441938]
Re; Re; Re; How foils lift

[Date/Time=05-27-2003 – 2:02 PM]

Name:Terry Hendricks thendricks@pacbell.net, [Msgid=442328]
Re; Re; Re; Re; How foils lift

ViewThread

[Date/Time=05-28-2003 – 8:30 AM]

Name:Ian Ward ianward@ozemail.com.au, [Msgid=442866]
re;

[Date/Time=05-28-2003 – 12:28 PM]

Name:Terry Hendricks thendricks@pacbell.net, [Msgid=443014]
re;

[Date/Time=05-28-2003 – 12:29 PM]

Name:Martin Grimm seaflite@alphalink.com.au, [Msgid=443016]
Thin sails vs Airfoils

[Date/Time=06-03-2003 – 9:21 AM]

Name:Ian Ward ianward@ozemail.com.au, [Msgid=446269]
Counter intuitive!

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[Date/Time=06-03-2003 – 9:40 AM]

Name:Ian Ward ianward@ozemail.com.au, [Msgid=446282]
Variable geometry foils

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[Date/Time=06-05-2003 – 4:35 PM]

Name:Scott Smith ssmith@syntheon.com, [Msgid=447702]
Paddlewheel Hydrofoil

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[Date/Time=06-08-2003 – 4:37 AM]

Name:Mark Lape mlape@attbi.com, [Msgid=448885]
Paddlewheel Hydrofoil

//archive.foils.org/yourown.htm

[Date/Time=06-08-2003 – 4:44 AM]

Name:Barney C. Black webmaster@foils.org, [Msgid=448886]
Lift coeffs for surface-piercing vee foils

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[Date/Time=06-09-2003 – 10:16 AM]

Name:Eugene Clement Eclement5@aol.com, [Msgid=449347]
Foil-Borne Draught

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[Date/Time=06-10-2003 – 4:08 PM]

Name:Mike K. ame2000@lycos.com, [Msgid=450211]
Foil benefits

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[Date/Time=06-11-2003 – 6:37 AM]

Name:Scott Smith ssmith@syntheon.com, [Msgid=450522]
Lift Coefficients for Surface Piercing foils

ViewThread

[Date/Time=06-11-2003 – 12:03 PM]

Name:Martin Grimm seaflite@alphalink.com.au, [Msgid=450715]
Paddle Wheel Hydrofoil

[Date/Time=06-11-2003 – 12:15 PM]

Name:Martin Grimm seaflite@alphalink.com.au, [Msgid=450724]
Good News Really

ViewThread

[Date/Time=06-11-2003 – 6:58 PM]

Name:Mike K. ame2000@lycos.com, [Msgid=451045]
performance

[Date/Time=06-12-2003 – 8:13 AM]

Name:Scott Smith ssmith@syntheon.com, [Msgid=451290]
New Info on Hydrofoil Sailboard Design

//archive.foils.org/miller.htm
[Date/Time=06-15-2003 – 6:30 AM]

Name:Barney C Black webmaster@foils.org, [Msgid=452967]
Hydrofoil Surfboard Details Wanted

ViewThread

[Date/Time=06-24-2003 – 9:11 PM]

Name:Merv Rice MervLaura61585@aol.com, [Msgid=459271]
Re; Hydrofoil Surfboard Details Wanted

http://archive.foils.org/popvideo.htm

http://archive.foils.org/sailbord.htm

[Date/Time=06-24-2003 – 9:24 PM]

Name:Barney C Black webmaster@foils.org, [Msgid=459280]
Hydrofoils ? Available

[Date/Time=07-14-2003 – 8:06 AM]

Name:Barry Steele bsteele971@hotmail.com, [Msgid=462263]
Re; Variable geometry foils

ViewThread

[Date/Time=07-11-2003 – 5:56 AM]

Name:Graeme Paulin paulin@paradise.net.nz, [Msgid=468029]
Re; Re; Variable geometry foils

[Date/Time=07-12-2003 – 3:38 AM]

Name:Malin Dixon gallery@foils.org, [Msgid=468623]
foiling vs planing

ViewThread

[Date/Time=07-28-2003 – 2:10 PM]

Name:Steve Rhodes srhodes@domus-usa.com, [Msgid=477506]
Re; foiling vs planing

http://www.exigent.info

http://gerard.delerm.free.fr/clair/b_page2a.htm
[Date/Time=07-31-2003 – 6:56 PM]

Name:Barney C Black webmaster@foils.org, [Msgid=479692]
Force Calculation

ViewThread

[Date/Time=08-01-2003 – 2:08 AM]

Name:Dan daniel@cmmaustralia.com, [Msgid=479875]
Re; Force Calculation

markhh@fencepost.com

[Date/Time=08-03-2003 – 6:19 PM]

Name:Mark Hursthouse markhh@fencepost.com, [Msgid=481140]
Re; foiling vs planing

http://naca.larc.nasa.gov/reports/1955/naca-report-1232/

http://naca.larc.nasa.gov/reports/1958/naca-report-1355/

[Date/Time=08-04-2003 – 6:39 AM]

Name:GœGard Delerm gerard.delerm@free.fr, [Msgid=481324]
Re; Force Calculation

[Date/Time=09-01-2003 – 5:03 PM]

Name:Tom Speer m3@tspeer.com, [Msgid=498264]
Re; foiling vs planing

[Date/Time=09-01-2003 – 5:17 PM]

Name:Tom Speer m3@tspeer.com, [Msgid=498274]
Re; Re; Variable geometry foils

[Date/Time=09-01-2003 – 5:30 PM]

Name:Tom Speer m3@tspeer.com, [Msgid=498276]
Re; Thin sails vs Airfoils

ViewThread

http://www.tspeer.com/temp/wm10m35r10a08.JPG

[Date/Time=09-01-2003 – 6:14 PM]

Name:Tom Speer m3@tspeer.com, [Msgid=498303]
Re; Counter intuitive!

[Date/Time=09-01-2003 – 6:56 PM]

Name:Tom Speer me@tspeer.com, [Msgid=498328]
re;

[Date/Time=09-01-2003 – 7:05 PM]

Name:Tom Speer me@tspeer.com, [Msgid=498332]
Re; Foil-Borne Draught

[Date/Time=09-01-2003 – 7:20 PM]

Name:Tom Speer me@tspeer.com, [Msgid=498339]
Re; Re; Foil-Borne Draught

ViewThread

[Date/Time=09-02-2003 – 10:19 AM]

Name:jim hynes jhynes@socal.rr.com, [Msgid=498668]
Re; Re; Re; Foil-Borne Draught

[Date/Time=09-03-2003 – 11:43 AM]

Name:Martin Grimm seaflite@alphalink.com.au, [Msgid=499571]
Re; Re; Thin sails vs Airfoils

[Date/Time=09-05-2003 – 1:23 AM]

Name:Ian Ward ianward@ozemail.com.au, [Msgid=501163]
Re; Re; Re; Foil-Borne Draught

jhynes@socal.rr.com

[Date/Time=09-06-2003 – 2:35 AM]

Name:Mac Stevens stevensm@earthlink.net, [Msgid=501924]
re; Thin Sails vs Airfoils
…even in development classes and sailboards, which have no real limitations, full wing sections are not used today….why? Is this perhaps because the benefits are not really there?

http://www.steamradio.com/JSYD/Dogstar50-article.html

The air drag of the hull alone is nearly equal to the total water drag of the hull.

http://www.tspeer.com/Planforms/Fig08.gif

was

last

…d) What seems to be missing in the comparisons I have seen, is that as wind strength increases, the camber of a thin sail is automatically reduced, which also significantly reduces the drag. This is not necessarily the case for aerofoil sections which are generally, for practical reasons unable to alter thickness with wind strength, hence their camber is not optimised and as a result their drag can in fact be higher than the much flatter thin sails as the wind strength increases. None of these effects seem to be addressed in the discussions and conclusions presented…..or am I missing something?

http://www.basiliscus.com/ProaSections/AppendixD/N65012n.jpg

http://www.basiliscus.com/ProaSections/Paper/FiveSection10n.JPG

http://www.tspeer.com/temp/wm10m35r10a08.JPG

http://www.tspeer.com/temp/wm10m35r10a04.JPG

http://www.tspeer.com/temp/mc10mxxr10.jpg

e) I believe, that comparisons should therefore be made at different wind strengths between the lift /drag ratio of say a 15% camber assymetric foil and a thin foil with the lift of a 15% camber section at low speeds and 5% camber at high speeds.

f) The net effect is that thin foil “normal” sails actually perform better than aerofoils in light airs and are exceedingly effective at reducing drag at high speeds by automatic camber reduction, which makes them very competitive with thick aerofoils.

This may give a more realistic picture and perhaps explain why we do not see big benefits in using wing sails.

I have tried to analyse data in the texts with this in mind, but always find the data lacking enough detail to make a proper comparison. Perhaps you have better data available and can make a good comparison.

[Date/Time=09-06-2003 – 2:35 PM]

Name:Tom Speer me@tspeer.com, [Msgid=502133]
Re; Foil-Borne Draught

[Date/Time=09-06-2003 – 2:40 PM]

Name:Tom Speer me@tspeer.com, [Msgid=502138]
re;

[Date/Time=09-06-2003 – 3:08 PM]

Name:jim hynes jhynes@socal.rr.com, [Msgid=502153]
Re; Paddle Wheel Hydrofoil

[Date/Time=09-07-2003 – 9:37 PM]

Name:Mark Lape mlape@comcast.net, [Msgid=502793]
Re; Paddle Wheel Hydrofoil

[Date/Time=09-10-2003 – 9:58 AM]

Name:Martin Grimm seaflite@alphalink.com.au, [Msgid=504503]
Re; re; Thin Sails vs Airfoils

[Date/Time=09-12-2003 – 5:57 PM]

Name:Ian Ward ianward@ozemail.com.au, [Msgid=506238]
Journal of Fluids Engineering Article

ViewThread

[Date/Time=09-12-2003 – 6:27 PM]

Name:Andrey Leonov aleon@aha.ru, [Msgid=506251]
Source of Pressure Envelope Data Needed

http://www.worldspeedsailing.com/event_fr.html

[Date/Time=09-13-2003 – 9:04 AM]

Name:Andrey Leonov aleon@aha.ru, [Msgid=506506]
re; JFE and other ASME Articles

http://searchojps.aip.org/

[Date/Time=09-14-2003 – 3:39 PM]

Name:Barney C Black webmaster@foils.org, [Msgid=507105]
Re; re; JFE and other ASME Articles

[Date/Time=09-15-2003 – 8:42 AM]

Name:Andrey Leonov aleon@aha.ru, [Msgid=507445]
re; Cavitation Inception

astolfi@ecole-navale.fr

http://www.ecole-navale.fr/fr/irenav/cv/astolfi/astolfi_cavitation.htm

[Date/Time=09-15-2003 – 9:13 PM]

Name:Barney C Black webmaster@foils.org, [Msgid=507898]

Hydroplane-foil R/C hybrid?

ViewThread

[Date/Time=09-28-2003 – 2:13 PM]

Name:Mike Kolder mikek13@netzero.net, [Msgid=516042]
Re; Hydroplane-foil R/C hybrid?

[Date/Time=09-29-2003 – 10:59 AM]

Name:jim jhynes@socal.rr.com, [Msgid=516453]

FOIL ASSISTED CATAMARAN

[Date/Time=12-29-2003 – 5:56 PM]

Name:Michael jaworski nmdesigns@sympatico.ca, [Msgid=564395]
Image Attached: “foil1.jpg” Click Here To View
FOIL ASSISTED CATAMARAN

ViewThread

[Date/Time=12-31-2003 – 10:53 AM]

Name:Michael jaworski nmdesigns@sympatico.ca, [Msgid=565051]
Image Attached: “2cat.jpg” Click Here To View
Re; FOIL ASSISTED CATAMARAN

[Date/Time=01-02-2004 – 4:46 AM]

Name:gunther migeotte gunther@cae.co.za, [Msgid=565671]
Surface Ventilated Supercavitating Foils

[Date/Time=04-23-2004 – 9:13 AM]

Name:Terry Hendricks thendricks@pacbell.net, [Msgid=635624]
building foils

[Date/Time=07-10-2004 – 4:15 PM]

Name:WAYNE deac@xtra.co.nz, [Msgid=677503]

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The International Hydrofoil Society (IHS) Hydrofoil Message: Chats, Info Sharing, Networking
General: IHS Administration Design of Foils: Foil-Struts-Controls-Performance Design of Vessels: Hull-Machinery-Costs-Performance/Ops History of Hydrofoils: People-Vessels-Operations Hydrofoils: Commercial Hydrofoils: Military
Hydrofoils: Models Hydrofoils: Pleasure Hydrofoils: Sailboats R/D: Student Projects/Thesis etc. Sources, Buy/Sell: Brokers-Builders-Designers-Operators Miscellaneous:Hybrids-Other High Performance Vessels-etc.
Searching the Archived Data Base of the
International Hydrofoil Society (IHS) Hydrofoil Message: Chats, Info Sharing, Networking
returned these results:

Design of Vessels: Hull-Machinery-Costs-Performance/Ops Scroll To Top Top

Archived Messages

Count,MessageID,category,ShortTitle,Message,Date,UserName,MsgPswd,Phone,Email,ParentMsgId

“1”,”912645″,”3″,”Re; Re; Re; A faster pontoon boat||912645″,”FYI: Several people around the USA are working on adding foils to pontoon boats… hobbyists, not manufacturers. Their correspondence with IHS is archived and accessible. Go to the main IHS page at www.foils.org and use the PicoSearch Engine to look for the word “pontoon.” That will lead you to several citations.”,”2005-10-12″,”Barney C Black”,”poopdeck”,” “,” “,”911944”

“2”,”911944″,”3″,”Re; Re; A faster pontoon boat||911944″,”There’s a company in Canada www.u-fabboats.com that I have shared what I learnedand are planning to offer a foil kit on there pontoon boats. It will be a hydro-foil assisted with a fixed foil in the tunnel. Which will reduce wetted surface I guess thats what it’s all about? I been playing around with a fixed foil and have had much luck with it I was focusing on slow speed. 12 mph and she’s on a plane and thats at gross weight I am planing a motorsailing cat around this concept.”,”2005-10-12″,”Mike”,”nopswd”,” “,”info@buildboats.info”,”888662″

“3”,”888662″,”3″,”Re; A faster pontoon boat||888662″,”I have thought about this as well. Trick is, don’t get too high out of the water. It is tempting to want to run the hull 3 feet out of the water to skim through wakes, but a sudden drop will be more than the hull was designed for. Lifting the hull 10 inches will give you speed and fuel economy, with less structural risk. Raising and lowering an outboard is a great way to accomplish powering the boat. I would be concerned about what will happen when the foils hit something (and they will). A front foil centered between the hulls could pivot back up between the hulls. The rear foil or foils could be fixed to the structure behind the hulls, and pivot up when trailering or running shallow. The trick (as I have learned from my dynafoils) is to have the rear strut mounted so that the foil is in front of the pivot point. That is, the rear strut(s) would go from the pivot point at an angle, the bottom of the strut forward of the top of the strut. Helps keep weeds off too. Why is this important? If the rear strut is vertical and operates on a pivot, after striking debris the strut would begin to pivot backwards. As it does the foils angle of attack changes. At some point in the travel the foil will be perpendicular to the drag load placed on it and it will not rotate up out of the water. Kiss your transom goodbye, keep pliers handy to pull your teeth out of the dashboard. If the foil is forward of the pivot things change. The foil will become perpendicular to the direction of travel while still well below the axis point. By the time the strut rotates far enough to line the center of drag up with the centerline of the structure, the foil is now operating backwards with positive lift. This forces the strut to continue rotating up and out of the water, saving you a lot of pain.
If you would like to take a look at the dynafoil system, or just talk, feel free to drop me a line. I just moved up from Miami to Stuart. By the way, a lot of talk goes into how to control roll in hydrofoils. While this is a concern with ships, I am convinced it is far less complicated with smaller boats. If you have ever ridden a bicycle I’m sure you have learned that you already have the ability to overcome roll issues with steering. After a while you don’t even realize you are doing it.”,”2005-09-05″,”Scott Smith”,”nopswd”,” “,”boatswithwings@adelphia.net”,”3″

“4”,”853019″,”3″,”Re; Re; A faster pontoon boat||853019″,”Good luck with your project. Hope this helps.

Bob’s Machine Shop make the motor lifting plates you need. You can find them at.

Home

Several catamaran builders and designers make the keel mounted foils systems you are talking about. See for instance the Hysucat Hydrofoil System.

http://admin.sun.ac.za/kie/unistel/technologies/foiltech.htm”,”2005-06-29″,”william white”,”nopswd”,” “,”whitewn@speakeasy.net”,”0″

“5”,”852923″,”3″,”Re; A faster pontoon boat||852923″,”I’ve been fighting that problem for some time. The easiest technique would be to jack the outboard motor up/down with spring-loaded and hydraulic jackplate. The rear foil which fits between the tubes, would move with the motor. A similar arrangement for the bow. If you allow the tubes to just skim the water that will keep the boat more stable. Make sure that going aground won’t be catastrophic. I’d love to find someone “local” to work with on my pontoon project. barry_steele@yahoo.com”,”2005-06-29″,”Barry Steele”,”nopswd”,” “,” “,”0”

“6”,”852922″,”3″,”Re; A faster pontoon boat||852922″,”I’ve been fighting that problem for some time. The easiest technique would be to jack the outboard motor up/down with spring-loaded and hydraulic jackplate. The rear foil which fits between the tubes, would move with the motor. A similar arrangement for the bow. If you allow the tubes to just skim the water that will keep the boat more stable. Make sure that going aground won’t be catastrophic. I’d love to find someone “local” to work with on my pontoon project. barry_steele@yahoo.com”,”2005-06-29″,”Barry Steele”,”nopswd”,” “,” “,”0”

“7”,”852376″,”3″,”A faster pontoon boat||852376″,”Living in Florida I spend a lot of my time on the water and most of it in the shallows. Pontoon boats offer the best way to take the party with me, slowly. A pontoon with retractable foils would be the best of both worlds. Any body out there tried this? I have given this a great deal of thought and have many ideas how to achieve this but expert advice is always welcome. Any advice where to look for info besides this excellent website would be greatly appreciated. Opinions on this would be welcomed aswell. “,”2005-06-28″,”Brian Scott”,”nopswd”,” “,”brian.scott.ctr@hurlburt.af.mil”,”0″

“8”,”792474″,”3″,”TUCUMCARI||792474″,”Hello,

For the past 26 years I have served as a project supervisor creating museum exhibits in honor of U.S. vets and those of our allies. Some of the venues I have done work for include the USS Intrepid Sea Air Space Museum and the Museum of Polish Military Heritage in America, both in New York City. Load my name Mike Dobrzelecki into a Google Search Engine and you’ll see examples of some of my work on two continents over the years.

I saw your name & email on the IHS website and hope you can provide some help on a research project concerning the Tucumcari PGH-2.

I built the old Aurora kit when it first came out in the late 1960’s early 1970’s (?) and not too long ago picked up a derelict unpainted damaged built-up, as well as a pristine complete kit still in the original box. I even still have some parts from my original build model.

My intent is to build one ‘flying’ and one in the water with its struts and foils folded up and possibly write a good article on the Tucumcari.

I have everything available on the internet for this fascinating hydrofoil, as well as, the old Sea Clasics issue with the Tucumcari on the cover. Recently, I obtained a copy of the History Channel Mail Call episode with the world’s most famous D.I. narrating exquisite video of the this fast-fighting boat in action – great footage, BTW. I have even manage to track down some of its crew for personal interviews. Most frustratingly, the crew I talked to so far all stated that their photos went missing during moves over the years.

I am looking for more photos including details of the interior, the exterior fit on the cockpit/bridge and upper surface of the hull and an answer to what’s in the large opening aft of the .50 cals and masts/antennae. I would also like to track down some more crew and any other books or naval history magazine articles on the the Tucumcari. Any leads would be appreciated.

Mike Dobrzelecki
3040 Clayton Street
Easton PA 18045
“,”2005-03-07”,”Mike Dobrzelecki “,”members”,” “,”Michael_Dobrzelecki@fwc.com”,”0″

“9”,”737553″,”3″,”Foil or Log?||737553″,”I don’t know what calculator you’re using, but if it’s telling you you can get good results from a section with a 50% thickness ratio and 25% “profile curvature” (camber?), I think you need to get a new calculator. These numbers sound like your foil section is a half-circle. Might there be just a little bit of flow separation coming off such a shape? “,”2004-11-13″,”Tom Speer”,”nopswd”,” “,”me@tspeer.com”,”0″

“10”,”737001″,”3″,”Hydrofoil Design Validation||737001″,”I downloaded a hydrofoil simulation calculator and wanted to verify the results I am getting.
Can someone tell me if the following numbers are accurate? I am trying to get the highest amount of lift I can for a constant water velocity over hydrofoil of 20m/sec or 38.9Knots. I am also trying to keep the foil span as short as possible.

Here are the input numbers:
Foil Area Square Meters: 1 Sq M (1M span X 1M chord)
Speed M/sec: 20 M/sec
density of water kg/m^3: 1000
thickness of foil divided by chord: 0.5
Aspect ratio (Foil span/chord): 1 “This is a square foil I know”
Angle of attack: 14.32 degrees
Profile Curvature: 0.25

The calculation is claiming that the hydrofoil would produce 53690 pounds of lift with these numbers. I need to make sure this is true and also that the wing is not in a stalled state on these numbers.
Greatly appreciated. Sidenote: Would anything change if I put a rectangular ducting around the hyrdrofoil? I know in airfoils and fans, the ducting produces more volume of airflow.
BE”,”2004-11-12″,”Foiled Again”,”nopswd”,” “,”mirequest@yahoo.com”,”0″

“11”,”732177″,”3″,”Re: planing hull seakeeping||732177″,”I don’t have a copy of these articles, but I would suggest contacting the Davidson Laboratory via their web page at:
http://www.stevens.edu/engineering/cms/
“,”2004-11-03″,”Barney C Black”,”poopdeck”,” “,”barney@alum.mit.edu”,”0″

“12”,”722280″,”3″,”planing hull seakeeping||722280″,”I am looking for copies of Gerard Fridsma’s two publications:

Fridsma, G., “A Systematic Study of the Rough-Water Performance of Planing Boats,”Davidson Laboratory, Stevens Institute of Technology Report 1275, Nov. 1969.

Fridsma, G., “A Systematic Study of the Rough-Water Performance of Planing Boats – Irregular Waves Part II,”Davidson Laboratory, Stevens Institute of Technology Report 1495, March. 1971.

Can anybody supply me with copies of these?”,”2004-10-12″,”Gunther Migeotte “,”nopswd”,” “,”gunther@cae.co.za”,”0″

“13”,”699947″,”3″,”Re: Engine Torque||699947″,”I have several small hydrofoils, probably similar to what you are trying to do. They are called Dynafoils (a search of the archive will turn up pics for you)and are about 8′ long, similar to a one-person sit-down waverunner. They were available in two HP’s, a 26hp model, and a 36hp model. Neither used a torque convertor. They used 2 cylinder, 2 stroke snowmobile engines, direct coupled to a 90 degree gearbox, to a downshaft with an evinrude outboard lower unit. The 26hp unit used a 9-1/4″ dia. by 7″ pitch prop, the 36hp unit uses a 9×9 prop. My 36hp Dynafoil leaps out of the water pretty well, and does about 35 mph. If you like, I can send you pictures, videos, or you can stop by in Miami and go for a test ride 🙂

If you are considering a 4-stroke, also consider a rev-limiter.”,”2004-08-26″,”Scott Smith”,”nopswd”,” “,”ssmith@syntheon.com”,”0″

“14”,”694448″,”3″,”Re; Re; Re; Engine Torque||694448″,”Barry,
Thank you for the information. What make is the prop…
“,”2004-08-13″,”Philip”,”nopswd”,” “,”kernowii@sympatico.ca”,”0″

“15”,”693009″,”3″,”Re; Re; Engine Torque||693009″,”For my application I have purchased a variable pitch prop for my mercruiser outdrive. The 3 blades to the prop are spring loaded with a lower pitch (around 16) for getting out of the hole and up on the foils. When the engine picks up speed, centrifugal force rotates the blades for up to about 25 pitch. This keeps the engine running within a fairly tight speed range. They are available for outdrives, outboards and inboards.”,”2004-08-11″,”Barry Steele”,”nopswd”,” “,”barry_steele@yahoo.com”,”0″

“16”,”692414″,”3″,”Re; Engine Torque||692414″,”Philip,

I would have expected that torque converters would rarely be required for small craft such as you describe. These devices result in a loss of power between the engine and the propeller and so a more efficient solution would be to select an outboard and propeller combination with an optimum gear ratio and propeller pitch to diameter ratio.

Hydrofoils have a resistance versus speed curve that means they require a relatively high thrust at takeoff speed and after that the resistance curve is more flat. Some larger hydrofoils (such as the Supramar PT 150) therefore had torque convertors of some form fitted to cope with this characteristic such that the engine would not be overloaded during takeoff but would run near optimally at cruise speed. For a smaller hydrofoil, there would typically be a surplus of power across the full speed range, but you may be adopting an outboard with relatively low power output so the takeoff condition may become critical for your boat.

Note that when using gearing in an outboard, the following relationship applies:

Power = (Torque) x (Rotational Speed)

Metric units for this equation are Watts, Nm and rad/s respectively.

Put another way, if you use a reduction ratio of 2:1 then the propeller shaft RPM will be half the engine RPM but the torque available at the propeller will be double that at the engine output shaft (neglecting any losses in the gearing due to friction). You can play with gearbox ratios until you obtain the required torque and RPM combination you need at the propeller. “,”2004-08-10″,”Martin Grimm”,”nopswd”,” “,”seaflite@alphalink.com.au”,”0″

“17”,”687245″,”3″,”Engine Torque||687245″,”I’m currently reviewing a design for a small one-person hydrofoil powered by a 15hp-25hp long shaft outboard. The question of engine torque has arisen and the need for an engine mounted torque converter however; in reading a lot of the design material on these pages (excellent guidance by the way) I have yet to come across this issue being discussed. Is torque a major design consideration on small (<9 feet) hydrofoils?","2004-07-30","Philip","nopswd"," ","kernowii@sympatico.ca","0" Propulsors Arneson Drive For Sale [2 Feb 02] This asd 6 drive is for sale. I think it would be a good drive for a hydrofoil. The drive is like new. Price $1,900. Credit cards OK. -- Fred Rodolf (FREDRODOLF@aol.com) [Date/Time=03-23-2002 - 12:33 AM] Name:webmaster@foils.org [Msgid=237120] Safety Safety Rules [2 Sep 97] I read in the Summer '97 issue of the IHS Newsletter about the American Bureau of Shipping (ABS) rules for high speed craft and will order a set. Do you know if there is a set of Coast Guard rules for safety? --Stan Siegel ( stansiegel@aol.com). Response... [2 Sep 97] The U. S. Coast Guard publishes a multi-volume "Marine Safety Manual" which can be downloaded from their website in Adobe Acrobat format. The Table of Contents does not mention high speed craft specifically, but there may be info buried in the individual chapters. The USCG (and IHS) participated actively in reviewing the International Maritime Organization's (IMO's) safety standards for high speed craft, published as Chapter X of the International Convention for the Safety of Life at Sea (SOLAS), available from from various booksellers. See the IMO home page for more info. -- Barney C. Black ( webmaster@foils.org). [Date/Time=03-23-2002 - 12:35 AM] Name:webmaster@foils.org [Msgid=237121] Archive; Bigger Wakes For Wakeboards Click Below to Open. https://foils.org/bigwake.htm [Date/Time=03-24-2002 - 2:07 AM] Name:Webmaster@foils.org [Msgid=237510] Archive; Design Texts, Software, Sources Click Below to Open https://foils.org/texts.htm [Date/Time=03-24-2002 - 3:30 PM] Name:webmaster@foils.org [Msgid=237692] Archive; Ultra-Hi Speed Hydrofoils Click below to Open https://foils.org/knots.htm [Date/Time=03-24-2002 - 4:09 PM] Name:webmaster@foils.org [Msgid=237699] Archive; Info on Books, Films, Articles Click Below to Open this Archive. https://foils.org/media.htm [Date/Time=03-25-2002 - 2:52 PM] Name:Webmaster@foils.org [Msgid=238065] Archive; Engines Sources, Maint, Repair Click Below to Open this Archive. https://foils.org/engine.htm [Date/Time=03-25-2002 - 3:10 PM] Name:Webmaster@foils.org [Msgid=238073] Archive; Commercial Operating Costs Click Below to Open this Archive. https://foils.org/opcost.htm [Date/Time=03-25-2002 - 3:45 PM] Name:Webmaster@foils.org [Msgid=238096] Archive; Drag Reduction Click below to Open Arcive: https://foils.org/drag_reduction.htm [Date/Time=04-20-2002 - 6:22 PM] Name:webmaster@foils.org webmaster@foils.org, [Msgid=249644] Archive; Seakeeping / Motion Sickness Click below to Open Archive: https://foils.org/seakeeping.htm [Date/Time=04-20-2002 - 6:33 PM] Name:webmaster@foils.org webmaster@foils.org, [Msgid=249650] science fiction ViewThread I have written a science-fiction novel on an imaginary watery planet and have included hyrofoil vessels. I'd like to know if my fictional use and description of hyrofoils seems possible and accurate. Floatplanes with hydrofoil struts: These planes are about the size and speed of a Piper Cub although lighter due to use of carbon fiber components. It can also fly as a glider. The hydrofoil struts fold while the craft is in air flight. The wing fold when the craft opperates as a boat. A propulsion device, which runs off of a hydrogen fuel cell delivers periodic burst of power. The cadence of the burst can be adjusted to coordinate with air and water conditions. This planet has no fossel fuels and so energy efficency is of utmost importance, thus the importance of a engine that can be turned off when not needed. Sail hydrofoils: I imagine them as small and lightweight for carrying two people with no cargo. They have auxilary power provided by the same propulson device that is on the aircraft. The propulsor is used get onto step quickly. I'd like to know about how tacking works with hyrofoils. How close to the wind do you need to be to stay on step? A friend of my thought it would only work on a reach. My story includes a scene with a battle between a guy in the aircraft and a bunch of guys in the sail hyrofoils. The guys in the sail hyrodfoils mounted howitzers onto their crafts (they were not designed for this usage) If they shoot in the wrong direction, while healed over, the boat capsizes. The guy in the aircraft has a laser cutter which doesn't do much unless he strikes sensitive parts of the hydrogen tanks.(His craft can't carry the batteries or other power source for a big laser) Does this sound reasonable? [Date/Time=08-30-2002 - 4:20 PM] Name:Lizzie Newell lizzie-n@gci.net, [Msgid=303576] science fiction All sounds well, with a few small points. Sailboats rely on momentum to carry them through a tack. The same momentum keeps the boat foilborne. Some hydrofoil sailboats like the Windrider have trouble staying up while tacking, but that is because of the control system, not the foils. The Hobie Tri-foiler tacks while foilborne with no trouble. Also, recoil from a gun would not cause the boat to capsize. Foils can pull down on one side of the boat as well as push up on the other, which also means that a well designed hydrofoil sailboat doesn't heel. Plus the recoil is so short lived it would be absorbed by the mass of the hull and the foils wouldn't even need to react. However, such a recoil would likely damage the structure of the boat. Fire a large caliber rifle, it doesn't have time to push you off your feet, but it will hurt like hell if it's not tight to your shoulder. A more troublesome device for a hydrofoils would be something that induce prolonged thrust, like a mini-gun (electric gatlin gun). A high power rifle will not knock you over, but a 9mm machine gun (much lower power) will certainly push you off your feet if you are not braced for it. Fired forward it would produce a reaction thrust that would slow a boat down. Backwards it would add to the thrust of the boat (not a problem for a foil). Sideways would be like being on a reach in a strong wind. The foils would have to adjust, and the extra angle of attack would induce drag. But if the direction of fire is slightly to the rear, the pressure on the hull would increase it's speed, just as the pressure on the sail in a reach adds to the hull speed. You might want to look up something called a "gyro jet". It was a pistol cartridge invented a while back that used a sort of spin-stabilized rocket propulsion. Artillery is too heavy for a hydrofoil sailboat. Simply put, twice the weight, four times the drag. The Gyro jet was almost recoiless, required a much lighter gun, and I believe is the technique used by many hand-held flareguns today. As far as how close to the wind you can sail a hydrofoil boat, wind direction is only a problem as it relates to hull speed. If a sailboat can achieve 20 knots 15 degrees into the wind, so can a foilborne sailboat. The most likely problem would be going downwind. A sailboat is always slower than the wind going downwind. A 10mph wind would not be likely to keep any hydrofoil sailboat up on it's foils, not matter how efficient it is. Hope this was of some use, Scott [Date/Time=09-03-2002 - 9:09 AM] Name:Scott Smith ssmith@syntheon.com, [Msgid=304776] science fiction/fact Some additional sailing hydrofoil information: there is a whole new type of sailing hydrofoil(though Monitor was actually the first) being developed around the world: the monofoiler. These boats are stabilized(generally ,but not always) by the crew; they are basically monohulls not multihulls such as the Rave and Trifoiler.You can see an overveiw of some of these boats at:http://www.monofoiler.com These boats can sail on as few as two foils and are a new wave in sailng hydrofoils. Sailing hydrofoils most certainly can sail downwind at speeds substantially higher than wind speed: they do it by tacking downwind(actually and technically-gybing) .A well designed foiler can point as well as "normal" sailboat and at any rate it's VMG(speed made good to windward) will be better. At least one new monofoiler, the Dancer, has been designed to jump: the flying system is controlled by the skipper and ,at will, he can twist the hiking stick, pull the trigger and jump clear of the water(!)--just for the fun of it! [Date/Time=09-24-2002 - 9:37 AM] Name:Doug Lord lorsail@webtv.net, [Msgid=313865] Hydrofoils are more than speed Why is speed always the focus when reading about hydrofoils? Consider the following: 1. Today in Sweden (Scandinavia, EU) the price/US gallon of diesel is about USD3.90 to USD4.00 due to tax 2. 95 % of all running time of pleasure boats takes place in smooth weather with moderate wave sizes (in fact the waves that cause irritation, not problems, are those generated by other boats, not the weather/wind. This is due to the large protected water areas by the archipelagoes surrounding Scandinavia and also due to rather low statistic average wind (force 2-3, Baltic coast areas) 3. The trend for pleasure boats is not always towards larger size but more towards comfort and luxury, etc., which makes the boats heavier. A 25-ft powerboat costs almost double the price in 2002 compared to the price of the same length craft a few years ago (including correction for inflation) 4. The average cruising speed is 22-26 knots even if top speed is 32 -40 knots. In fact, the average speed very seldom surpasses 22 – 26 knots. Rather often you see powerboats in the size 25 to 40 ft operated at 12 – 17 knots albeit they are built for higher cruising speeds. When I ask people why they are running their boat this way, frequent answers are: for comfort and/or economy/mileage reasons. The comfort factor is important (i.e. not to have to reduce speed frequently when meeting waves from other boats/ferries etc. which in fact now is the case. It is not due to poor performance of the boat – it is for better comfort, sometimes noise factor, compared to cars. Having these aspects in mind, the relatively simpler design task of hydrofoils for smaller boats compared to ferries may be could open up opportunities if comfort, noise, and mileage are focused on instead of just the high speed performance. [Date/Time=10-15-2002 - 7:16 PM] Name:Tomas Järnmark Tomas.Jarnmark@electrum.se, [Msgid=324184] Read a Good Book Lately? Are there today any sort of updated standard “bible” books (for designers, producers, students, etc.) that summarize what is acknowledged know-how (R&D, field experiences, truths & myths, designs, developments, costs, performances, bench marking comparisons etc)? If so where can I order these? [Date/Time=10-15-2002 - 7:17 PM] Name:Tomas Järnmark Tomas.Jarnmark@electrum.se, [Msgid=324185] Do Foils Equal Comfort? ViewThread Is a hydrofoil-based boat in the size of 27 ft more comfortable (cut through larger waves with better comfort, movements, splashes, etc.) at 25 knots than a surface-planing boat of the same size and speed? [Date/Time=10-15-2002 - 7:20 PM] Name:Tomas Järnmark Tomas.Jarnmark@electrum.se, [Msgid=324187] Do Foils Equal Comfort? Yes, [Date/Time=10-27-2002 - 7:30 PM] Name:Harry Larsen hlarsen0@gte.net, [Msgid=329671] Yes, Foils Equal Comfort! Harry should know. Visit his most interesting website at http://home1.gte.net/hlarsen0/ [Date/Time=10-29-2002 - 7:13 PM] Name:Barney C Black webmaster@foils.org, [Msgid=330715] Fibreglass Ship Manufacturing I am writing on behalf of one of my friends who lives in Iran. He is an inventor and would like to inquire for some information on manufacturing a fibreglass ship with 500 tonnes capacity in the merchant sector. It would be a greatly appreciated if you would alert me to any information resources on modeling, manufacturing (ship and or fibreglass). and the possibility of using fibreglass in this case? [Date/Time=12-20-2002 - 3:37 AM] Name:Mehrdad Tavana m30tavana@yahoo.com, [Msgid=353812] NACA 0015 Pressure Distribution ViewThread I'm looking for the theoretical pressure distribution (considering an invicid flow) for different angles of attack, for the NACA 0015. [Date/Time=03-25-2003 - 7:43 PM] Name:R. Sosa rsosa@fi.uba.ar, [Msgid=403003] Re; NACA 0015 Pressure Distribution I have access to a program called WingAnalysis Plus which is able to calculate the pressure coefficients for a range of foil types. You can purchase a copy of that program via the internet though I don’t have the website address at hand. I have calculated the distribution of pressure coefficients for the NACA 0015 foil at a range of angles of attack from 0 to 10 degrees at 2 degree increments. The results are attached as an Excel spreadsheet. Remember that these results are obtained from a theoretical method and so don’t represent measured test data. I can’t promise the results are accurate. I believe it should also be possible to derive the Cp distribution around a NACA 0015 foil at various incidence angles by reference to the text book “Theory of Wing Sections” but I have not yet done so myself. If you have found better (experimental) data, perhaps you can post a message letting people know where that data can be found. [Date/Time=05-28-2003 - 11:54 AM] Name:Martin Grimm seaflite@alphalink.com.au, [Msgid=442981] Attached File "NACA0015CpvsAoA~xls.zip" - size 54784 Click Here To Download X-Craft Press Release ViewThread Titan Wins Contract To Build Navy's X-Craft San Diego - Feb 26, 2003 - The Titan Corporation of San Diego said Tuesday that it has been awarded a $59.9 million contract by the U.S. Navy's Office of Naval Research (ONR) to develop and build the Navy's "X-Craft". The X-Craft will be a high-speed aluminum catamaran consisting of an advanced hull geometry, designed to give the craft speeds of 50 knots or more. Initially it will be used by ONR for purposes of hydrodynamic experimentation to include the addition of advanced lifting bodies and polymer drag reduction techniques. The X-Craft's deck will have two helicopter landing spots capable of handling a variety of aircraft up to the size of the H-60 helicopter series. With a design displacement of approximately 1,100 long tons, the 80m. long by 22 m. wide X-Craft will be self-deployable and of flexible design for spiral technology insertion. A Combined Gas Turbine or Diesel (CODOG) propulsion plant will propel the X-Craft to speeds of 50 knots or more. The CODOG propulsion plant is expected to consist of two GE LM-2500 gas turbine engines totaling 50,000 hp and two MTU 16V595 16-cyl 4380 kW diesels driving KaMeWa 125SII waterjets through Renk gearboxes. The vessel's Mission Module Bay will be capable of fully supporting multiple mission packages simultaneously. Titan also announced that it is awarding to Nichols Bros. Boat Builders, Inc., a subcontract to provide hull, mechanical, and electrical ship systems for the U.S. Navy's new X-Craft. This award to Nichols Bros. completes an RFI and RFP effort initiated by Titan less than six months ago. Nichols Bros. Boat Builders, headquartered in Freeland, (Whidbey Island) WA, specializes in the building of high-speed catamarans and other vessels. Work on the X-Craft was expected to begin in May 2003 and deliver in August 2004. A later phase of the program will add a lifting mid-body and a polymer injection system. [Date/Time=07-26-2003 - 8:18 AM] Name:Greg Bender glbender@erols.com, [Msgid=476489] Re; X-Craft Press Release See the Hydrofoils:Military category of this BBS for a thread of recent discussion on the X-Craft. [Date/Time=07-27-2003 - 8:58 AM] Name:Barney C. Black webmaster@foils.org, [Msgid=476922] Hydrofoils vs Tunnel Hulls? ViewThread Given that the two are of similar weight and power, which is generally faster and has less drag, a hydrofoil, or a tunnel hull (like raceboats)? I know that the two work very differently, and am very intersted in finding the answer to this question. [Date/Time=12-31-2003 - 6:15 PM] Name:Timothy Shaw slickmod@hotmail.com, [Msgid=565242] Re; Hydrofoils vs Tunnel Hulls? Hi Timothy, Although I am a hydrofoil enthusiast, my gut feeling is that for relatively calm water powerboat racing applications, the tunnel hull (such as unlimited hydroplanes) would come out as having less drag and hence translating to more speed than a hydrofoil design for the same installed power. Tunnel hulls seem to just skim over the water on the ends of their three(?) planing surfaces when at speed, so it is hardly a case of them having excessive wetted surface area which is what leads to frictional resistance. On the other hand, a hydrofoil design, even with only the very small hydrofoils that would be needed to support a relatively light boat at such high speeds, would still incur the additional drag of the supporting struts. The high speed would also mean that supercavitating foils are likely to be required and these don't tend to have particularly high lift to drag ratio's. Some means of surface sensing would probably also be required to control the foil angle of incidence so that the craft remains stable. This would probably mean using a planing surface sensor with associated drag as well. I would be delighted to hear that the opposite is that case, but then why are there no hydrofoils competing in "unlimited" powerboat races? Surely it is not just as simple as that nobody has thought about trying this idea or that hydrofoils are not permitted by the rules of an "unlimited" race!? By the way, hydroplanes do seem to make use of hydrofoils of sorts (probably also supercavitating foil sections?), in way of high aspect ratio skegs mounted on one side of the hull as a means of aiding in getting a "grip" when going around the circuit. They don't help lift the boat, if anything they stop it from toppling over in a sharp turn. At least that is my understanding. Perhaps you can enlighten us more about those devices? [Date/Time=01-01-2004 - 10:40 AM] Name:Martin Grimm seaflite@alphalink.com.au, [Msgid=565409] Re; Re; Hydrofoils vs Tunnel Hulls? Martinn, I am aware of at least one person who was involved with hydroplane racing that looked at putting supercavitating foils on the sponsons. I believe he petitioned APBA (American Power Boat Association) but do not know the outcome. This individual died last year, he was in his late 90s. He was also involved in the Boeing High Speed Test Craft in its early trials. Sumi Arima [Date/Time=01-02-2004 - 1:05 PM] Name:IS. Arima arimas1@juno.com, [Msgid=565775] Re; Re; Hydrofoils vs Tunnel Hulls? It doesn't seem likely that anyone using a hydrofoil will successfully compete against tunnel hulls, unless they come up with something radically different. It doesn't really matter whether you are discussing the small, sheltered water tunnels (commonly called a pickle fork), or the big, open water cats. Both of these boats are now capable of very high speeds. Since at these speeds they are no longer pushing a bow wave, the induced drag is very low. The drag from any foil system at 100mph+ becomes very high, regardless of how well designed or made the struts and foils are. Ask one of the open water boat designers how much drag force the skegs have to handle, you might be surprised at the answer. But a large part of the problem is control systems. Even with a good, fast system for controlling the foils, at those speeds the slightest glitch would be a disaster. The occaisional rogue wave has destroyed many a racers dream for victory. I remember when a 40 foot cat nosed into a rogue wave and was driven straight to the bottom, killing both crew members while doing almost no damage to the boat. Imagine what could happen if you managed to get a negative angle of attack on a foil for even a fraction of a second at 100mph. It would be catastrophic. And the smaller sheltered water boats can easily pull more than a G in a fast corner, the slightest tracking error induced by a foil or strut would be equally destructive. But being a foil enthusiast as I am, I would love for someone to prove me wrong. 🙂 [Date/Time=01-23-2004 - 8:19 AM] Name:Scott Smith ssmith@syntheon.com, [Msgid=576707] Re; Re; Hydrofoils vs Tunnel Hulls? Timothy and Scott From my perspective at speeds of 100knots and up the US Navy in the Seventy's built Two 100 Ton, 85 ft Surface Effect Craft to explore the potential. One was powered by Partially Submerged Supercaavitating Propellers (most racing surface drives are direct descendants of these) and the other powered by two stage axial waterjets. Both these craft were essentiall very fine hulled catamarans at high speed. Just a couple of feet of the aft length of their hulls were in the water at speed, and then only a couple of inches deep. This along with aft fins/rudders provided directional stability. The lift fans and Skirts kept the hulls out of the water at lower speeds, say 0 to 60kts), but at very high speed thay almost operated like a pure tunnel hull with a very wide tunnel. Both these vessels used the air cushion to control the heave and pitch of ride at very high speeds. They had response frequencies of up to 100hz and needed it. But they worked very successfully. To prevent the catastrophic pitch-ins you desribed, the Navy did a lot of research in shaping the above water shape of the Cat hulls and the Bow cross structure ramps between the hulls. One of them even had above water anti pitch foils attached at the bow that were a last resort to prevent pitch-ins. During there 10 year lifetimes they operated in all sea conditions offshore (greater 10+ significant wave height). The only reason they ever slowed down was for visibility or the crew got tired of the beating when in severe seas. Most Hydrofoilers consider that the Navy's PHM hydrofoils had the highest performance, but they only went about half the speed of these SES. The great benefit of the hydrofoil especially the fully sbmerged type on the PHMs was the ability of the active ride control system on those foils to level out the ride in waves less than 10 ft significant height. They could also operate in even higher seas but would start to countour the swells in these very high seas. I worked on the ride control systems for all these craft and it was indeed state of the art then and easily now to control the actuators at the very high frequencies needed to keep them safe. As for resistance. Both Hydrofoils and Tunnel Hulled Cats can be very efficient or very Inefficient according to the skils of the designer. On average. most tunnel hulled cats at high speed (100kts) are close to fifty percent more efficient than hydrofoils. There are a lot of people in IHS who would disagree with me there. The reason why is that the propulsion efficiency has to be accounted for too. In the PHM the waterjets were mounted very high 12 feet above the water and had lots of losses especially in the zee shaped water inlets. The two Navy SES 100 ton vessels had about a twenty percent speed difference for about the same power due also mostly to the difference between the Waterjet (lower efficiency) and the Partially Submerged Supercavitating Propellers (high efficiency and no struts or exposed prop shafts). Design is all about choices, and a good Naval Architect can make any of these hull forms into a reasonably well performing vessel. Enjoyed your comments Bill White [Date/Time=01-26-2004 - 8:31 AM] Name:Bill White whitewn@speakeasy.net, [Msgid=578306] Transport Efficiency of Hydrofoils etc Hi Bill, Good to see we are not all only passionate about hydrofoils and can see merit in other forms of high speed marine craft. Naval Engineers Journal, February 1985, page 211 indicates that the maximum speed of SES 100A was 80 knots (approx) and SES 100B was 90+ knots. Displacements were 289,650 lb (129.3 tons) and 206,000 lb (92.0 tons) respectively while total installed power (lift and propulsion) was 15,000 HP and 15,360 HP respectively. In comparison PHM displacement was 249.7 tons (NEJ, Feb 85, page 173) and power was 17,000 HP (page 161). Speed was 50 knots plus. Comparing calm water transport efficiency (displacement x speed / power) we have approximately: SES 100A = 0.690 ton.knots/HP SES 100B = 0.539 ton.knots/HP PHM = 0.734 ton.knots/HP So it could be said that SES 100B was roughly 30% more efficient than the PHM even given its higher maximum speed. The question I have is how do hydrofoils, SES, monohulls, catamarans etc compare when it comes to sustained speed for a given power in a seaway? Also in the February 1985 issue of the Naval Engineers Journal on page 57 Michael Eames presents charts of sustained speed in a seaway for 200 ton and 1000 ton vessels of various types. These charts indicate that the achieved speed of a low length to beam ratio ACV or SES falls rapidly with increasing wave height (from 80 knots in calm water to 40 knots in 2 metre significant wave height), while the notional 200 ton hydrofoil has a far more gradual speed degradation with increasing seastate (remains close to 50 knots in up to 4 metres significant wave height). It would be good to get some more specific data on the relative performance of various craft types as sea state increases. [Date/Time=01-31-2004 - 9:51 AM] Name:Martin Grimm seaflite@alphalink.com.au, [Msgid=581470] Transport Efficiency of Hydrofoils etc Hi Martin, I agree fully with your comparison of hydrofoils and SES. An interesting document was published called "Hull Form and Propulsor Technology for High Speed Sealift revised: 13 February 1997". Contact Chris Mckesson for a copy. The whole document is 45MB. Perhaps we can put it in the IHS website? The document compared the transport efficiency of different kinds of craft and their conclusions wer very similar: for state ofthe art vessels of each type, SES and air cushion vehicles offer the best transport efficiency. Hydrofoils were superior to planing, semi-planing and semi-displacement craft for volume Froude numbers (Fnd) of about 3.0. I have compared the hydrofoil-assisted catamaran data I have and it turns out they offer improved transport efficiency compared to regular hydrofoils -about 30% better - and offer improvement in transport efficiency from Fnd=2.20. No data was given in the report for varying sea states and I agree it would be very interesting to know how these compared for differing sea states. [Date/Time=02-02-2004 - 3:56 AM] Name:Gunther Migeotte gunther@cae.co.za, [Msgid=582312] Transport Efficiency of Hydrofoils etc Martin and Gunther Thanks for the feed back. The Speeds quoted in the Naval Engineers Journal for all these vessels (100A, B and PHM were all under quoted by about five knots here and almost everywhere else during their active duty times. Since the diferrential was just about constant accross the board your efficiency comparisons should stay the same. The speed impact of sea state on the vessels was never reported in the public domain with any accuracy. The PHM hydrofoils had by far the smoothest ride. They could maintain foilborne operations through sea state five. (10ft sig wave ht) And with care during operations they could often stay foilborne up well into sea state 6. But if you came off of foils in high sea states 10 ft sig wave and above it was difficult to get them foilborne again. Their hull borne sea keping was excellant as well but at speeds of 10kts or less. The SES and ACVs were also very good in rough seastates. When cushionborne, they would slow down due to the added wave resistance while still at full power through SEA State 5 the same as the PHMs. In Sea State 6 and up they would usually reduce speed for personnel safety. The ride was never as smooth as the PHMs but they still went faster through most of the operating envelope of sea state (0-6). We have very little operational information in even higher sea states, but the SES 200 which was closer to the PHMs in size, did operate at 20+ kts in a Hurricane in the Gulf of Mexico while performing a rescue mission with the Coast Guard when none of the Monohull 100 plus foot Cutters would go out. I can attest to the SES 200's excellent seakeeping having been aboard for a nonstop voyage from Norfolk to Halifax in early winter. The effect of the ride control system on that vessel was very impressive. Most of the published seakeeping papers on these craft were severly compromised by politics and arbitrary motion limits on the feasible operating envelope. Even the SWATH papers often were conservative. Thanks again Bill White [Date/Time=02-03-2004 - 8:06 PM] Name:Bill White whitewn@speakeasy.net, [Msgid=583540] Transport Efficiency of Hydrofoils etc Gunther and Bill, Thanks for your comments and additional insights on this subject. I am looking at transport efficiency data at the moment as a personal interest which was also prompted by a recent paper which briefly compared hydrofoil supported catamarans against other types of high speed craft. The document on high speed sealift sounds like one that would be worthwhile reading, though my interest is in passenger-only craft at the moment. These are more suited to application of hydrofoils than multi-thousand tonne sealift ships. [Date/Time=02-10-2004 - 10:22 AM] Name:Martin Grimm seaflite@alphalink.com.au, [Msgid=594015] hull choices ive sailed moths for a while and am considering a new hull for foiling, i only have one question: does a planing hull beat a displacement hull to 10 kts boat speed in lighter wind conditions. what im trying to acheive is lift off in a wind range between 5 - 10 kts and after that i would like a low aerodynamic drag hull. im thinking of something similar to a formula sailboard for its planing but am concerned about the wetted surface area as opposed to a displacement hull similar to a rowing skull. although i only have 11 feet of LOA (width currently runs around 1ft) ps: consider the weight of each hull to be the same. [Date/Time=02-11-2004 - 9:02 AM] Name:glen oldfield compositedesign@hotmail.com, [Msgid=594722] Transport Efficiency of Hydrofoils etc THe sea lift paper is quite good as it covers wide range of ships from passenger vessels right up to the USS "United States" and covers all the different concepts in high speed craft including, semi-displacement craft, planing craft, hydrofoils, air cushion craft, hydroplanes, sea sleds etc. It also gives state of the art examples of each. I would bery much like to see your paper on transport efficiency comparisons of different types of craft. Can you post it on the IHS website? [Date/Time=02-12-2004 - 11:44 AM] Name:Gunther Migeotte gunther@cae.co.za, [Msgid=595556] Transport Efficiency of Hydrofoils etc Gunther, I am still collating and cross checking the vessel performance data where possible. When I have completed it as far as I can go, I will see how it can be made available via the website. [Date/Time=02-14-2004 - 9:04 AM] Name:Martin Grimm seaflite@alphalink.com.au, [Msgid=596590] Effect of Marine Groth on Hydrofoil Craft ViewThread I have recently had some discussions with fellow hydrofoil enthusiasts about the subject of marine growth on the foils of hydrofoil craft and how best to protect against this. It has been an aspect of hydrofoil operation that has always been a bit of a mystery to me. On several occasions I have read or heard that it is necessary to regularly clean the foils (and presumably also the hull) if hydrofoil craft are to maintain good take-off and foilborne performance. Without such regular cleaning, I recall reading that the Rodriquez hydrofoils on Sydney Harbour could even experience difficulty taking off with a full passenger load. More recently I have been told that a European operator of hydrofoils prefers to clean the foils every four weeks, either by lifting the craft out of the water or by sending a diver down to do this work underwater. Of course, either option adds to the running expenses and could become costly. A review of hydrofoil operations in the November 1969 issue of Hovering Craft and Hydrofoil magazine also indicated that a Scandinavian operator also docked each hydrofoil every four weeks for two days of cleaning and overhaul. I would be interested to hear whether any rule-of-thumb or more precise means of assessing the impact of marine growth on the performance of a hydrofoil is available? For displacement vessels, a rule-of-thumb allowance for the effect of marine growth is to add 0.1% to the total frictional resistance for each day in service after the vessel has received a fresh anti-foul paint coat. After 6 months, that equates to about 18% additional frictional resistance at a given speed, or more realistically, a speed reduction for a given engine power output. None the less, due to the form of the resistance curve for monohulls and catamarans, this additional drag will probably slow the vessel down in a fairly linear fashion with each day out of dock. In the case of hydrofoils, I can imagine the power margin available to become foilborne when fully loaded could be relatively small and so the craft may struggle to become foilborne with only moderate fouling. To further complicate matters, marine growth may cause a reduction in lift of the foils at a given speed in addition to the increase in frictional resistance. The analogy to this situation is the build up of ice on aircraft wings, which can have a drastic impact on both lift and drag. I am also interested to hear views on the best means of minimising marine growth on the foils so that the period between cleaning of the foil surfaces can be maximised. For example, would highly polished stainless steel foils (as used on many Russian hydrofoils, Jetfoils and some Supramar hydrofoils) offer better resistance to marine growth than the more typical high tensile steel which requires some form of surface coating to prevent corrosion? If a surface coating is to be used, has any information been published on that subject with specific application to use on the foils of hydrofoil craft? [Date/Time=02-28-2004 - 8:43 AM] Name:Martin Grimm seaflite@alphalink.com.au, [Msgid=604934] rtiEffect of Marine Groth on Hydrofoil Craf Dear Martin, the most useful reference on hydrofoil fouling that I have found is in Marine Technology: Experimental Investigation of {Eneromorpha Clathrata} biofouling on Lifting Surfaces of Marine Vehicles, Marine Technology 38(1) pp31-50, January 2001. I think that paper will answer most of your questions. If you are a SNAME member you should be able to download it off their website. [Date/Time=03-01-2004 - 10:20 AM] Name:Gunther Migeotte gunther@cae.co.za, [Msgid=605863] View Messages Search Messages Return to Home Page Frequently Asked Questions This board has been viewed 21676 times since Apr-20-2002 . (Total Views Since Board Creation on Mar-21-2002 is 22410.) Questions about this board, email: bbs@foils.org System Support, Email: support@bulletinboards.com To Learn About Bulletin Boards: Click Here Bulletin Board Management Site: Click Here (321) 984-9080 © 1997 - 2004 P.A. Corp. V7.1

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