(Last Update 14 Dec 07)
While on vacation in 1994, my family and I came upon a small maritime museum (Musee Maritime Bernier) across the river from Quebec, Canada. On display, and open to the public during certain hours, was the Fast Hydrofoil Escort FHE 400 (HMCS BRAS D'OR). Unfortunately the museum was closed when we arrived and were not able to tour the ship. The exterior appeared to be in excellent condition.
To put this picture of the FHE 400 in perspective, the ship had a full load weight of 200 tons, a length of 151 ft, a hull beam of 21.5 ft, and a foil span of 66 ft. Crew size - 29. She was designed by DeHavilland, completed in 1967, and arrived in Halifax, Nova Scotia on 1 July 1968 to begin a long series of trials. From September of 1968 until July 1971, when the trials terminated, the ship logged 648 hours, 552 hullborne, and 96 hours foilborne. The most operationally representative trial was a 2,500 mile voyage to Hamilton, Bermuda, and Norfolk, Virginia, in June 1971. Foilborne, BRAS D'OR exceeded her calm-water design speed, achieving 63 knots at full load in 3 to 4 foot waves.
The Canadians are to be congratulated for saving this glorious ship from the scrap pile. Click Here For More Information.
The Canadian requirement for a hydrofoil centered about the Anti-Submarine Warfare (ASW) role which demands an extremely versatile ship. Michael Eames, in his paper "A Review of Hydrofoil Development in Canada" presented at the first International Hydrofoil Society Conference, Ingonish Beach, Nova Scotia, Canada July 27-30, 1982, pointed out that an alternative to improving sonar range (on large ships) is to provide a significantly larger number of sonars economically - the so-called "small and many" concept. Initial detection requires long endurance at slow search speeds; interception and attack require short bursts at speeds exceeding those of conventional ships. The stability of the hydrofoil, hullborne and foilborne, made it the smallest ship capable of sustained operation in the open ocean.
With this philosophy firmly in mind, and continued confidence from their earlier developmental effort, the Canadians undertook in 1959 a study of design requirements for a nominal 200-ton ASW hydrofoil ship designated R-200. The design concept that resulted was reviewed in January 1960 by experts from the United States, United Kingdom, and Canada with the conclusion that the concept was sound. By this time the U.S. was well underway with their program to construct a 120-ton ASW hydrofoil, HIGH POINT, with a fully-submerged foil system and autopilot control. It was agreed that the U.S. and Canadian approaches would be complementary in expanding the data base and providing the opportunity for comparison of two quite different designs.
In August 1960 a contract was awarded to DeHavilland Aircraft of Canada to carry out engineering studies and to determine the technical feasibility of the R-200 design. Based on the positive conclusions that resulted, a second contract was awarded to develop a preliminary design. Other work was also supported to carry out model tests and an in-depth examination of some of the more critical system details. In May 1963 this led to award of a three-phase contract to DeHavilland which called for preparation of contract plans and specification, detailed design and construction, and the conduct of performance trials. DeHavilland, in turn, subcontracted fabrication of the hull and installation of ship systems to Marine Industries Ltd. in Sorel, Quebec.
Hull construction of BRAS D'OR commenced in 1964, but during construction, on 5 November 1966, there was a disastrous fire in the main machinery space which almost caused termination of the program. In spite of the delays and cost increase, however, the ship, designated FHE-400 and named BRAS D'OR, was completed in 1967.
The surface-piercing foil system of this hydrofoil is very evident from the photo. The main foil carries about 90% of the lift, whereas the small bow foil carries the remaining 10%. The latter is steerable and acts like a rudder for both foilborne and hullborne operations. It can also be adjusted in rake, enabling the best angle-of-attack to be selected for foilborne or hullborne operation under whatever load or sea conditions that may exist. As in many hydrofoil designs, the different power levels involved in hullborne and high-speed foilborne operations dictate separate propulsion systems. The accompanying illustration shows the layout of BRAS D'OR's propulsion system. For the lower-power, long endurance hullborne system, fuel weight is a critical factor which made the selection of a high speed diesel engine a logical one. A Paxman 16 YJCM diesel rated at 2,000 hp drove two three-bladed propellers on pods mounted on the main anhedral foils. These 7-foot diameter, fully-reversible, controllable-pitch propellers were 30 feet apart in the lateral direction which provided excellent maneuverability at low speed through differential pitch control.
The foilborne propulsion system consisted of a Pratt & Whitney FT4A-2 gas turbine engine, rated at 22,000 hp, driving two fixed-pitch, three-bladed propellers 4 feet in diameter. The propulsion drive system was similar in many ways to the PLAINVIEW propulsion layout.
BRAS D'OR arrived in Halifax, Nova Scotia on 1 July 1968 to begin a long series of trials. From September of 1968 until July 1971, when the trials terminated, the ship logged 648 hours, 552 hullborne, and 96 hours foilborne. The most operationally representative trial was a 2,500 mile voyage to Hamilton, Bermuda, and Norfolk, Virginia, in June 1971.
The biggest disappointment, albeit from a scientific point of view (but not the sailor's aboard), was that the amount of significant rough-water data collected was regrettably small. At no time during the trip were limiting rough-water conditions experienced, either hullborne or foilborne.
This was not to say that BRAS D'OR did not encounter rough water! According to Michael Eames, who describes highlights of these trials in his paper cited above, HMCS FRASIER, a 3,000-ton frigate sailing in company during a rough water trial sent a signal as follows: "Weather conditions were considered most unpleasant, heavy seas and 15-20 ft swell, wind gusting to 60 knots, ship spraying overall with upper deck (of FRASIER) out of bounds most of the time. BRAS D'OR appeared to possess enviable seakeeping qualities. She was remarkably stable with a noticeable absence of roll and pitch, and apparently no lack of maneuverability. The almost complete absence of spray over the fo'c's'le and bridge was very impressive."
Foilborne, BRAS D'OR exceeded her calm-water design speed, achieving 63 knots at full load in 3 to 4 foot waves. Sea trials included a comprehensive set of seakeeping and motions data, all of which prompted the Canadians to conclude that BRAS D'OR showed its performance to be quite remarkable for a surface-piercing hydrofoil ship. A variety of teething problem interfered with the progress of BRAS D'OR's trials. These involved the hullborne transmission system, the bow foil pivot bearing, the foil-tip and steering actuators, the electrical system, and the hydraulic pumps. None of these proved to be insurmountable problems however, and steady progress was made in overcoming them.
In July 1969, BRAS D'OR was docked to repair persistent foil-system leaks, and a large crack was discovered in the lower surface of the center main foil. When the neoprene coating was removed, an extensive network of cracks was found, some at least entering into the spar and rib members of the sub-structure. A replacement foil element was constructed, but later, it too developed severe cracking.
This Canadian hydrofoil project was not curtailed and the ship laid up due to foil cracking, as some believed. Success of the trials was recognized, and it was appreciated that a production class of this ship would not employ the same foil material. The real reason for the curtailment was a change of defense policy announced in the White Paper on Defense issued in August 1971, which assigned priority, not to Anti-Submarine Warfare (for which the BRAS D'OR was designed) but to the protection of sovereignty and the surveillance of Canadian territory and Coastlines.
The FHE-400, although no longer operational, remains even today the most sophisticated and advanced design of a surface-piercing-type hydrofoil. Its design and extensive trials program contributed significantly to the technical data base and this was invaluable in complementing the U.S. development program.
The Canadian Institute of Marine Engineering - CIMarE of 8090A Rte Trans Canadienne, St. Laurent, Quebec H4S 1M5 published this artical on the Bras D'OR in their Sept 2007 Newsletter: More can be found at their web site at: http://www.CIMarE.org/
"Vessel Retrospective: BRAS D'OR, Canada's High Flyer - the World's Fastest Warship"
[16 May 01] Here are few pics of a Canadian hydrofoil I saw during my trip to Quebec last April... It was in a naval museum, I don't remember the name ...(closed anyway in April). You can see the St Laurent behind the boat. -- Antoine Lenormand (email@example.com)
[16 May 01] The vessel is the BRAS D'OR, and the museum is the Musee Maritime Bernier. -- Barney C. Black (Please use the BBS to reply)
[4 Jul 02] The name of the maritime museum you're writing about is Musée maritime du Québec. Hope you enjoyed the tour, even if we were closed ! From a guide of the hydrofoil. -- Famille Chouinard-Bédard (firstname.lastname@example.org)
FHE-400 BRAS D'OR Dimensions for Model...
[8 Sep 00] Can you tell me where I can find "dimensional drawings" for the Canadian FHE-400 hydrofoil destroyer ? I wish to make a 40" model of her that actually flies ( yes I have the technical ability). The only thing I have found is the book "The Flying 400" by Thomas G. Lynch. -- The book gives the length as 151 Feet but no usable drawings -- Dan MacLean (email@example.com)
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