| F.B.25 | |
|---|---|
 | |
| General information | |
| Type | Two-seatnight fighter |
| Manufacturer | Vickers |
| Primary user | Royal Flying Corps |
| Number built | 1 |
| History | |
| First flight | Spring 1917 |
TheVickers F.B.25 was a British two-seatnight fighterprototype ofWorld War I designed to attack enemyairships. Completed in 1917, it failed in its official flight tests that year and no order for production resulted.
In 1916,Vickers Limited designed a two-seatpusher configurationbiplane fighter, the F.B.23, to replace its obsoleteVickers F.B.5 andF.B.9 "Gunbuses". A number of versions of the FB.23 were planned depending on the engine used, with possible powerplants including a 150 hp (119 kW) Salmson water-cooledradial engine, a 150 hp Hart air-cooled radial engine and a 200 hp (149 kW)Hispano-Suiza 8V-8 engine. The pusher configuration was obsolete however, compared to prospective tractor aircraft such as theBristol F.2 Fighter, which was both faster than the estimated performance of the F.B.23 and carried a heavier armament, so Vickers abandoned the F.B.23 without an example being built.[1]
Vickers reworked the F.B.23 to form the basis of a two-seatnight-fighter, the F.B.25, to compete with theRoyal Aircraft Factory N.E.1 to meet a British requirement for a night fighter capable of attacking Germanairships. The F.B.25 used an identical tail and tail boom assembly to the F.B.23, but had modified wings and a completely new fuselagenacelle.[2]
The F.B.25 was atwo-bay biplane with unstaggeredwings of equalspan. Its nacelle was mounted between the wings, was unusually wide for an aircraft of its type in its day, and accommodated the two-man crew, a pilot and a gunner, in staggered side-by-side seats, with the gunner's seat ahead and tostarboard of the pilot's.[2] The gunner was armed with a single1.59-inch Breech-Loading Vickers Q.F. Gun, Mk II, popularly known as the "Vickers-Crayford rocket gun," which despite its popular name was a lightweight 40 mm single-shot gun that firedshells and had norocket-launching capability.[3] Its tailbooms converged in elevation to meet at the rear spar of thetailplane. It had a singlepropeller, mounted in apusher configuration. The aircraft had an oleo-pneumaticundercarriage, an unusual feature for the time.[2][4]
Plans called for the F.B.25 to mount a smallsearchlight in the nacelle's nose, have a nosewheel to reduce the chance of the aircraft turning over during night landings, and use the same 200-horsepower (149-kilowatt) Hispano-Suiza 8 planned for the F.B.23. As design and construction progressed, Vickers made changes; the searchlight and nosewheel were deleted, and as the 200-horsepower engine was unavailable, Vickers substituted a 150-horsepower (112-kilowatt) Hispano-Suiza.[2]
Vickers completed the F.B.25 prototype in the early spring of 1917. Company flight testing revealed poor characteristics. The prototype was sent toMartlesham Heath in June–July 1917 for official testing, and official reports declared that the F.B.25 had poor control characteristics, being "very dangerous" with the engine off, and "almost unmanageable in a wind over 20 miles per hour" (32 km/h). The aircraft was condemned as being completely unsuited for use as a night fighter. No further aircraft were built, and the lone F.B.25 later crashed at Martlesham Heath.[5][6]
Data from War Planes of the First World War:Volume Three Fighters[5]
General characteristics
Performance
Armament
Aircraft of comparable role, configuration, and era
