Aeroplane Aviation Archive — Issue 33 The World’s Fastest Aircraft

(^16) UNITED KINGDOM
RAF SE5a
Max Speed: 138mph (222km/h)
Engine: Wolseley W.4a Viper
Power: 215hp
Length: 20ft 11in (6.37m)
Wingspan: 26ft 7.5in (8.11m)
Height: 9ft 6in (2.89m)
Armament: 1 x  xed 0.303in Vickers
machine gun and 1x
0.303in Lewis machine
gun on Foster mount
Max T/O weight: 1,976lb (896kg)
Range: 300 miles (483km)
without its pilot having to fear the onset of
structural failure. It is unsurprising, therefore,
that the SE5a was the mount of most of the
RFC’s leading aces. The  rst unit to employ
it, ‘Fighting Fifty-Six’, was also the most
successful, being credited with 401 victories by
the end of the war, and producing numerous
Below: RAF engineers made a serious attempt to organise a functional instrument panel. This saw
gauges for the oil temperature, oil pressure and radiator temperature grouped near the altimeter,
airspeed indicator and compass on the right side of the instrument panel.
The need for speed
The key to the success of the SE5/5a was its V8 liquid-cooled engine, initially in the form of
the direct-drive 150hp Hispano-Suiza 8A. After 77 SE5s had been built with this powerplant,
production switched to the SE5a, which was  tted with the geared 200hp Hispano-Suiza 8B
engine. Production of this engine under licence by Wolseley Motors Ltd initially proved
problematic due to unreliability. Things only started to improve when Wolseley modi ed a
150hp engine into the high-compression, direct-drive W 4A Viper of 200hp. This engine was
vastly superior increasing the SE5a’s top speed by a full 7mph and improving its rate of climb.
It was faster, though less manoeuvrable, than the Camel. With the Camel revelling in medium
to low altitude combat, the SE5a was the superior aircraft at altitudes exceeding 10,000ft.
Therefore, squadrons equipped with the  ghter tended to be used more for aerial combat at
medium to high altitudes, and much less in the air-to-ground role. Furthermore, the SE5a’s
armament of one forward- ring Vickers machine gun in front of the pilot and a single Lewis
gun a xed to the top wing made the aircraft ideal for stalking high- ying prey. Pilots could
sneak up beneath a hostile machine, ratchet down the gun and  re up into the underbelly of
the enemy aircraft.
famous aces, two of whom – Albert Ball and
James Thomas Byford McCudden – were
awarded Britain’s highest military decoration,
the Victoria Cross (VC). By the end of World
War 1, 2,765 SE5/5as had been built, and
some 2,500 more would be completed before
production ceased in 1919.