The mythical beast: 1/48 Wyverns from Classic Airframes and Trumpeter
November 15, 2013 in Aviation
The Wyvern has to be one of the strangest airplanes to ever grace a carrier deck. The first turboprop, its ten years of gestation and failure as the FAA’s strike force paid off for the rest of aviation by solving the problems of controlling and operating turboprops.
I have for some reason always liked this airplane, it has a grace of its own. In the 1980s I did an ID Models vacuform (which was determined to be a “what if” model when shown at OrangeCon in 1988). Then the very nice Dynavector vacuform in the mid-90s, then the Classic Airframes kit in 2003 (sort of a limited-run injection molded Dynavector model), and finally the Trumpeter version in 2006. It’s one of Trumpy’s better kits (most likely because it didn’t start life as a Trumpy project, but was an acquisition from a company that failed to launch successfully), Nice petite surface detail, lots of ordnance, good decals, separate flaps, wing-fold option, etc. If you like weird airplanes, that kit’s a good candidate for a lot of fun.
W.E.W. “Teddy” Petter began development of what would become the Wyvern as his last project at Westland before leaving for English Electric where he would design his masterpiece, the Canberra jet bomber. Petter’s objective was to develop a long-range carrier-based day fighter with the ability to carry a torpedo or bombs as appropriate for a secondary role as an anti-shipping strike aircraft. The original design would have had the engine mounted amidships, a layout that had been tried for the Westland F.7/30 prototype of 1934. The favored engine at this point was the Rolls-Royce Eagle, a 24-cylinder liquid-cooled “H” type like the Napier Sabre, designed for an ultimate output of 3,500 horsepower. Further development was made official when the Naval Staff issued specification N.11/44, written around the Westland proposal. A mockup with the mid-mounted engine and nose-mounted cockpit found little support from the service pilots who would fly it, so a second mockup was created with the engine in the nose and the cockpit atop a significant hump in order to obtain a 15-degree angle of view over the nose for deck landing. By June 1944, the design was known as the W.34, though it was officially known as the N.11/44 until the adoption of the name “Wyvern” in 1947.
By August 1944, Westland began investigating the possibility of changing the powerplant to a turboprop. However, six Eagle-powered prototypes were ordered in November 1944. The planned turboprop was the Rolls-Royce RB.39 Clyde, which Rolls-Royce expected to deliver in December 1945. The N.11/44 prototype, which was the biggest British single-seat naval fighter type at the time, required a double fold of the wing, with the tips folding down in order to have clearance on the hangar decks of RN carriers. In order to launch from a deck, the airplane required a contraprop, which was developed by Rotol (8-blade) and DeHavilland (6 blade). This in turn led to a very large vertical fin to provide directional stability.
The first Turboprop Wyvern flew on January 16, 1949, powered by a R-R Clyde. While the Clyde exceeded initial performance estimates, it suffered from a variety of problems, not the least of which was that Rolls-Royce was committed to other engine projects, which kept them from focusing on solving the Clyde’s problems. The Armstrong-Siddeley Python was the only turboprop of the necessary power that could be used for the Wyvern. This change added at least two years to the development cycle as the engineers struggled to create a throttle control that would allow the engine to be rapidly throttled back for a carrier landing, or rapidly throttled up to make a go-around, the solution being an inertia control unit (ICU) that was, unfortunately, mechanically complex.
The Wyvern finally appeared from development as the S.Mk.4, and began to be delivered to RNAS Ford in May 1953 to equip 813 Squadron. These aircraft did not have the definitive engine control unit and thus were not carrier-compatible until these units were installed in the summer of 1954. The first operational Wyverns went aboard HMS Albion in September 1954, where it was discovered their problems were not over, as there were a series of flameouts during catapult launch as a result of fuel starvation under high-g loading while the aircraft were with Albion during a Mediterranean cruise. The Wyverns were offloaded at Hal Far, Malta, and remained there until March 1955 when they returned to England. A final design of the ICU/ECU unit solved the flameout problem. 813 and 827 Squadrons embarked aboard HMS Eagle in May 1955 for a second Mediterranean cruise, which gave the Wyverns some 1,500 operating hours and 1,000 landings, after which the aircraft was considered proven.
813 and 827 Squadrons returned from the Mediterranean and decommissioned in November 1955. They were replaced by 830 and 831 Squadrons which activated in January 1956. 830 Squadron went aboard HMS Eagle that May, destined to be the only unit to fly the Wyvern in combat, when their nine aircraft participated in six days of strikes against Egyptian military targets in the Suez Canal Zone in October-November 1956 as part of Operation Musketeer, the Anglo-French “intervention” in what was called “the Sinai War,” though that was really part of a conspiracy by the two western powers, working with Israel, to regain control of the Suez Canal following its nationalization by Egypt in 1955.
813 recommissioned in October 1956, giving the FAA three strike squadrons. With the decommissioning of 830 and 831 Squadrons in January and February 1957, 813 was the last Wyvern operational unit, embarking on HMS Eagle in July 1957 for a tour that lasted until March 1958. 813 decommissioned at Ford on March 29, 1958, which marked the end of active service for the Wyvern. 33 had been lost to all causes during its operational life. The survivors were all melted down during 1959, and the only Wyvern in existence today is the Wyvern Mk.1 VR137, which was never actually flown.
The Classic Airframes kit has the dark blue spinner, the Trumpeter the red spinner.
12 additional images. Click to enlarge