|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.|
Updated last February 27, 2005
Miscellaneous:Hybrids-Other High Performance Vessels-etc. Top
[16 Apr 98] After researching hydrofoils I conclude that they are far superior with respect to handling, performance, and comfort, than a normal displacing hull. So why then are they not used much anymore? In all my research I can only find one reason that sticks out: the foils can only be so big due to stress factors and drag. A huge ocean liner can carry much more than a hydrofoil, yet it is slower. Do you know of any other reasons, perhaps design drawbacks or facilities, the hydrofoil is becoming a prehistoric way of transport? -- Tristan Lee Andrews (email@example.com)
[19 Apr 98] First, regarding size, the foil lifting capacity is an area function, increasing with the square of the speed. So in the practical speed range of 40 to 50 knots with the size of the hydrofoil craft increasing by a cubic function, the foil dimensions become relatively quite large. A Navy study concluded that a 2,000 ton hydrofoil was about a limiting size. Range is another consideration. Hydrofoils can be shown to compete commercially with aircraft up to about 300 miles on a time basis for downtown to downtown routes. This takes into consideration time to and from airports and the ability of the hydrofoil to go downtown to downtown. Hydrofoils have demonstrated their ability to provide superior rough water passenger comfort. So in adverse sea conditions, sea state three and above, their ride quality and speed are better than other high speed seacraft. The real problem is that hydrofoils have a high first cost on the basis of cost per seat mile. It has been determined that the acquisition cost is the driving factor in most acquisition decisions. To increase the use of commercial hydrofoils, studies that I have been involved with indicate that there is a market for small, 100 to 300 seat capacities, at speeds in the 40 to 50 knot speed range, with submerged foils and automatic control systems. But the first cost has to be made more attractive than available hydrofoils on the market today. I would like to see some concentrated design effort put into this area by a responsible designer and builder. ? Robert J. Johnston
[18 Apr 98] I am also under the impression that interest in "the hydrofoil" is fading. Very few yards are pursing this concept. Rodriquez itself seems not to be interested in developing new ideas. Is there anything that can be done to foster a new breed of Hydrofoils? A few ideas: An agreement between IHS and Fast Ferry Magazine; Make available all studies carried out in the US on the field to all the interested parties via IHS web pages; Disseminate the hydrofoil ideas to all shipyards building fast ferries. -- Diego G. Mazzeo (firstname.lastname@example.org).
[21 Mar 98] I am trying to determine the possibilities and performance capabilities of using hydrofoil boats for personal yachting. I once rode on a trial craft that was to be utilized commercially in the Great Lakes (USA) but it never happened. This particular craft was about 60 feet long and was fast and smooth. -- Art Leo (email@example.com)
[21 Mar 98] I am presuming that you are speaking of motor yachts rather than sailing yachts. There are operating many hydrofoils of proven design operating in the size range you mention, though they are designed as ferries or tour boats. There are also several on the drawing boards waiting for someone to bankroll the detail design and development. I believe that one royal personage had a Boeing Jetfoil outfitted as a yacht in Saudi Arabia or a neighboring country. On a smaller scale, Harry T. Larsen, a Boeing employee, successfully added foils and an automatic control system to his Bayliner. Please spend some time exploring the links section of the IHS webs page. There is a South African and an Italian site that could interest you, also Harry Larsen's site. If you could provide any specifics on the nature of your interest... whether you are a the designer or the customer, areas in which the yacht is intended to operate, etc. that might help generate more useful info. -- Barney C. Black (firstname.lastname@example.org)
[Date/Time=03-23-2002 - 12:49 AM] Name:email@example.com [Msgid=237127]
[Date/Time=03-24-2002 - 3:33 PM] Name:firstname.lastname@example.org [Msgid=237693]
[Date/Time=04-24-2002 - 3:07 AM] Name:Capt Mark van Rijzen email@example.com, [Msgid=251014]
[Date/Time=05-10-2002 - 12:22 PM] Name:Dana firstname.lastname@example.org, [Msgid=257882]
"Hydrofoil provides launching ?lift?. This unusual appendage was fitted to the stern of the 43,000 tg [presumably Gross Tonnage] fishing parent and factory ship ?Vostok? for her launch from Admiraltisky yard, Leningrad. A hydrofoil strutted from a lattice after poppet structure provided a degree of lift prior to the buoyancy aft taking effect."
Note: Hovering Craft and Hydrofoil is now published as Fast Ferry International
[Date/Time=05-12-2002 - 7:02 AM] Name:Martin Grimm email@example.com, [Msgid=258418]
Attached File "largefoil~JPG.zip" - size 91448 Click Here To Download
This is just a note to tell you that I have added some more photos of WhizzyWig models to my web site, which you might like to see. One photo is attached to this email.
Visit : http://www.home-taylor.freeserve.co.uk/index%20ekranoplan%20man.html
or go direct to the WhizzyWig Gallery : http://www.home-taylor.freeserve.co.uk/whizzywig1/whizzywig%20gallery.html to see the pictures.
Also a new video clip of the prototype WhizzyWig XGE, flying in XGE mode (eXtreme Ground Effect) has been added to the Video section of The Wig Page, visit: http://www.se-technology.com/wig/
If you would like a set of plans to build your own WhizzyWig model see the details at : http://www.home-taylor.freeserve.co.uk/whizzywig1/whizzywig%20plans.html , or email me and ask for an order form for the WhizzyWig XGE Plans Pack.
I hope you enjoy the photo.
[Date/Time=05-29-2002 - 8:54 AM] Name:for Graham Taylor firstname.lastname@example.org, [Msgid=265027]
Attached File "WhizzyWig XGE p?ay02 00035~jpg.zip" - size 33390 Click Here To Download
I am a mechanical engineering consultant currently operating in the area of gas turbine component manufacture. I have an interest in
steering my future business towards the growing renewable energy industry, and for this end have an opportunity to become involved in the design of a 0.5 to 1.0 MW tidal turbine type project. I have designed and built a few small wind generators for college projects so have an appreciation for basic fluid dynamics, but having graduated from university in '85 and now because of a lack of practice, must admit my fluid dynamics expertise is rather 'rusty'.
The design areas I am particularly interested in: hydrofoil profiles /
lift / angle of attack / blade structural design - manufacture, dynamic similarity - modeling etc. I would appreciate your comments on this matter and look forward to hearing from you in the near future. -- Gene Hourihane, Rotamet Technologies Ltd., Ireland.
[Date/Time=06-19-2002 - 7:57 PM] Name:Gene Hourihane email@example.com, [Msgid=273493]
I know a few people who have adapted water pumps successfully to waterturbines to generate electricity off the grid at old Mills on rivers here in the US. The technology, to make these adaptions can be found on the Web at a number of Back-to-NATURE SITES.
To get more technical you should check out the technology behind WATERJET Pumps. These have become very popular over the last 15 years and as a result there is a lot of information available. The large ones used for passenger and car ferries might be close to what you need. There are a number of design codes out there in two and three dimensions that should be able to help you.
My experience was in the design of 40000 hp waterjet pumps for the US Navy's PHM Hydrofoils and Surface Effect Ships. They were all Very high speed two stage Mixed Flow devices similar to the the fuel pumps on NASA's Saturn 5 Appollo Moon rockets of the 60's/70's. You can find some usefull info still in the NASA Archives at their Web site.
Best of luck
[Date/Time=06-19-2002 - 11:25 PM] Name:Bill White firstname.lastname@example.org, [Msgid=273553]
[Date/Time=06-20-2002 - 7:43 AM] Name:William Hockberger email@example.com, [Msgid=273639]
[Date/Time=06-29-2002 - 1:59 PM] Name:C. Schramm firstname.lastname@example.org, [Msgid=276854]
I can.t help on these two vessels, but I know that there are people here who can answer your questions. There are experts in all kinds of advanced vehicles here, so feel encouraged to use this section of the Bulletin Board to talk about all kinds of craft.
[Date/Time=06-29-2002 - 7:15 PM] Name:Bill White email@example.com, [Msgid=276916]
I am much interested in Ekranoplan. For further understand and commercial industry in the Korea. I wish to contact with a consultant regarding Ekranoplan. If you could please assist me. Thank you.
[Date/Time=08-16-2002 - 8:09 AM] Name:Kunkiw Lee firstname.lastname@example.org, [Msgid=296625]
[Date/Time=08-18-2002 - 12:49 PM] Name:Ken Upton email@example.com, [Msgid=297585]
[Date/Time=08-20-2002 - 4:48 AM] Name:Bill Hockberger firstname.lastname@example.org, [Msgid=298312]
I'm curious as to how much my canoe's windward performance could be improved by using a pair of asymmetrical leeboards, one at a time on each tack.
Given a top speed of 4 knots to windward, and leeboard underwater dimensions of about 3 ft long by about 8 inches wide, what asymmetrical cross-section would be best: ie what max thickness, what front-to-back location of the max chord height, and is blunt entry better than sharp entry for the leading edge?
Does anyone have any sketches showing optimum cross-section for selected velocities thru the water at the 1-6 knot range? Would cavitation cause problems at this low a velocity?
[Date/Time=11-22-2002 - 4:42 PM] Name:Dan Reiber email@example.com, [Msgid=342085]
...what asymmetrical cross-section would be best? ...is blunt entry better than sharp entry for the leading edge?
You want to shape the leading edge as accurately as possible to the
coordinates of your chosen section. The right leading edge shape is neither blunt nor sharp. It's one of those Goldilocks things. It's better to be just right.
You might want to try one of Selig's model glider airfoils, like the S7012 http://www.nasg.com/afdb/show-airfoil-e.phtml?id=1055 or the S7075 http://www.nasg.com/afdb/show-airfoil-e.phtml?id=1057. They are intended to work well at low speeds.
Don't forget that the deeper you make your boards, the less drag due to lift there will be.
...the 1-6 knot range... Would cavitation cause problems at this low a velocity?
The foil will stall before you reach cavitation. You got no worries about cavitation with a canoe.
[Date/Time=11-23-2002 - 5:49 AM] Name:Tom Speer firstname.lastname@example.org, [Msgid=342291]
[Date/Time=12-04-2002 - 6:49 PM] Name:Barney C Black email@example.com, [Msgid=346886]
When the Soviet engineers were doing so much to develop ekranoplan technology, they designed them to be built in shipyards using high performance marine vehicle materials and processes, rather than in aircraft production facilities. They have to be able to live in a marine environment and to take a certain amount of pounding when landing and taking off, as well as minor wave impacts while flying. (Seaplanes have to endure much of the same, but they also have to be good airplanes and fly efficiently at altitude, so they're properly built in aviation facilities.)
I don't know of any focused consideration by our own Coast Guard and aviation regulators to sort this issue out, but I think it has been carried further in certain foreign areas, where ekranoplans have appeared to be nearer to actual use. I think Australia is one such, probably Russia, maybe Germany?
[Date/Time=12-04-2002 - 6:52 PM] Name:Bill Hockberger firstname.lastname@example.org, [Msgid=346887]
[Date/Time=02-10-2003 - 9:54 PM] Name:Betsy Fry Skymarketokc@aol.com, [Msgid=375871]
Sounds like your intriguing "hydrofoil ride over the grass" was probably a small hovercraft instead!There might be a hovercraft association or club in your neck of the woods that can help if you can't find the original vendor.Good luck.Garry Fry,I'm in Australia,no relation that I'm aware of!
[Date/Time=02-11-2003 - 8:53 AM] Name:Garry Fry email@example.com, [Msgid=376077]
It is difficult to imagine how the underwater wings of a hydrofoil could function on a grassy field. You may need to redefine your question.
[Date/Time=02-11-2003 - 8:50 PM] Name:Ray Vellinga firstname.lastname@example.org, [Msgid=376506]
And I've learned the difference between a hydrofoil and a hovercraft! Thank you very much!!!
[Date/Time=02-12-2003 - 8:54 AM] Name:Betsy Fry SkyMarketOKC@aol.com, [Msgid=376791]
If any one has information please call me.
Jonathan Javetz at:
706 714 4903
[Date/Time=05-30-2003 - 1:52 PM] Name:Jonathan Javetz email@example.com, [Msgid=444435]
[Date/Time=06-05-2003 - 6:27 AM] Name:Scott Smith firstname.lastname@example.org, [Msgid=447373]
2003 HP Symposium Series:
Human Powered Hybrids - Taking advantage of the surrounding environment
A Panel Discussion
Paul MacCready, Jake Free and Sid Shutt
Calif State Univ Long Beach Noon to 3 pm
Saturday October 25, 2003
Hydrobowl - $30.00 per boat entry fee. Free to spectators
100 meter flying start sprint
100 meter 10 pin slalom
2000 meter criterium
LB Marine Stadium, 8am-12noon
HPV day at the Encino Velodrome on Sunday the 26th
Contact Carole Leone, email@example.com
2003 HP Symposium Series:
Propeller Design for low power, high efficency
4 Sessions & Panel Discussion
Jake Free, Bill Patterson, Sid Shutt, Jack Norris and Andy Bauer
Monday October 27 at CSULB. Noon-4
714-744-8439 (eve) 714-403-5053 (cell) 626-812-2199 (m-f,7-3)
william.gaines@NGC.com (days)firstname.lastname@example.org (once a week)
HUMAN POWERED HYBRIDS:
Taking advantage of the surrounding environment
In the design of low or limited power systems energy utilization is critical. Clearly the direct energy source needs to be highly efficent. Indirect energy sources can be siginificantly exploited, and at times even exceed the contribution of the direct source(s). This Panel discussion will explore these issues and their application to human powered vehicles.
Some of the indirect sources that will be exploried are:
Sails, Kites, Special Propellers/Windmills, Solar Power, Surfing, Soaring on updrafts, as well as correctly riding water currents eddies and rip tides taking advantage of turbulances
Panel speakers = Paul MacCready, Sid Shutt, Jake Free
Propeller Design Individual sessions: Between 12:00 and 4:00 ET (Engineering Technology) Building at Long Beach State University
Jake Free: independently developed basic thoeries and advanced "Analogy" theories (marine)
Bill Patterson: helocopter applications of air propeller as well as "Minimum induced loss" (circulation) throries of Larribbee (air)
Andy Bauer and Jack Norris: Efficiency theories based on Theodorsen: "Minimum induced and minimum profile drag propellers made understandable" (especially air)
Sid Shutt: Taking characteristic LD curves/properties through to the build (including Reynolds integral); Proceeding from calculations to evaluating the result (primarily marine)
Propeller Panel Discussion "questions" to each method; motion to static thrust/helocopter / hovercraft? Similarities and differences of air and water propellers: sections, geometry, others
Paul MacCready: Paul has an academic background in Physics and Aeronautics and pioneered the use of instrumented sailplanes and powered aircraft in atmospheric measurements. He has won noumerous national soaring championships. The techniques he develpoed are standards used by pilots everywhere. His design of the ultra-light flight vehicles, Gossamer Condor, Albatross, solar powered Penguin, Bionic Bat, Solar Challenger and Helios expand the concept of the motto Do more with less. His work in recreating the giant pterodactyle featured in the IMAX movie On the Wing explored the earliest evolution of Earthling flight and its need to make use of the surrounding energy.
Sid Shutt- built the HYDROPED series which was the worlds second human powered hydrofoil to fly behind the Flying Fish. During the early years, the Hydroped and Flying Fish went back and fourth as keeper of the world speed records and DuPont Prize attempts. Hydroped was the first human powered hydrofoil to take off from the water. Along with being a pioneer in hydrofoil sailboats, Sid is without a doubt the worlds formost authority on designing and building human powered hydrofoil propellers!
Bill Patterson: Through being a professor at CalPoly, Bill and his students were the first humans to fly a human powered helocopter DaVinci III. They used minimum induced loss Larribee techniques for the propellers that powered the rotors for the 'copter. The roters themselves should also present a good perspective on human powered propellers!
Jack Norris and Andy Bauer: From being glider/sailplane champions to being tecnical director for the Voyager Aircraft Project (you know, the one that flew around the world on a single tank of gas?). Norris and Bauer will present efficiency theories, "Minimum induced and profile drag made understandable" based on Theodorsen.
Jake Free: Since 1985 after hundreds of propeller designs and thousands of installations including those for HP hydrofoils, displacement boats, single and multi seat, kinetic sculptures, submarines, (with first places too numerous to mention) his formulas and algorhythoms have been anathama to the public. In this presentation he will show techniques ranging from a :30 second estimate to a full-blown world class build using his own "analogy" theory.
The contact for details is Bill Gaines at GAINESW@aol.com
[Date/Time=10-03-2003 - 4:36 AM] Name:Bill Gaines GAINESW@aol.com, [Msgid=518983]
[Date/Time=10-21-2003 - 8:35 PM] Name:Waqas Kamran Ahmad email@example.com, [Msgid=529463]
[Date/Time=10-25-2003 - 7:45 PM] Name:Barney C Black firstname.lastname@example.org, [Msgid=532301]
[Date/Time=11-28-2003 - 9:51 AM] Name:Martin Grimm email@example.com, [Msgid=551215]
[Date/Time=02-17-2004 - 8:11 AM] Name:Paolo Chiarlone firstname.lastname@example.org, [Msgid=598160]
Image Attached: "esterne170119011702013540_big.jpg" Click Here To View
I would like to have informations about the aplications of this process.
[Date/Time=04-01-2004 - 12:08 PM] Name:Ga? Jouannic Gael.email@example.com, [Msgid=624747]
Most interceptors installed on ships are really not supercavitating at all.
A good source of information is the company Maritime Dynamics. They have designed and installed many interceptors worlwide. Their web site is at
They operate by changing the vertical pressure on the rear of the hull in front of the interceptors. This pressure change is caused by the interceptors blocking the flow of the boundary layer flow over the hull.
[Date/Time=04-01-2004 - 7:15 PM] Name:Bill White firstname.lastname@example.org, [Msgid=625025]
Yet I am still sure it exist cavitating spoiler put on the trailing edge of a foil: I am now studying it in Russia where it seems to be known for 30 years. But I miss information concerning their applications.
[Date/Time=04-02-2004 - 4:57 AM] Name:Ga? Jouannic Gael.email@example.com, [Msgid=625227]
[Date/Time=04-02-2004 - 8:05 AM] Name:William Hockberger firstname.lastname@example.org, [Msgid=625261]
Supramar AG in Switzerland has also been researching the use of foil profiles with a groove that promotes (or prevents?) supercavitating flow. I don't know if that was also intended to serve as a means of motion control. Some information about this work is on the Supramar website:
[Date/Time=04-15-2004 - 12:19 AM] Name:Martin Grimm email@example.com, [Msgid=631273]
[Date/Time=04-15-2004 - 7:11 AM] Name:Greg Bender GBender@Noesis-Inc.com, [Msgid=631329]
Martin, I can confirm your memory on Russian supercav torpedoes that used sharp edges on the nose to form a vapor cavity over the rest of the body to minimise skin friction drag and play with the boundary layer flow. You can find non technical papers on the subject in various hydrodynamic society papers over the last fifeteen years.
The US Navy has utilised the basic technology successfully on several projects over the years. But I am not aware of any published information on the subject.
I also have never heard the term "interceptor" used with the technology in this country though.
[Date/Time=04-16-2004 - 6:35 PM] Name:Bill White firstname.lastname@example.org, [Msgid=632302]
I agree it's not supercavitating - it's ventilated. The gas behind it is air, not water vapor.
[Date/Time=04-18-2004 - 7:20 PM] Name:Tom Speer email@example.com, [Msgid=633026]
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