Aviation Archive Issue 25 - 2016 UK

(Jacob Rumans) #1

18 HEAVY FIGHTERS OF WW


O


f all the twin-engined fighters of World War 2, the Westland Whirlwind was perhaps
the most promising. When it first flew in 1938, it was one of the fastest and most
heavily-armed combat aircraft in the world. However, it had the misfortune to be
powered by the unreliable Rolls-Royce Peregrine engine – had it been fitted with
Merlins, history might well have told a very different tale.
The only Westland fighter to achieve operational status with the RAF, the Whirlwind
was designed under the leadership of W. E. ‘Teddy’ Petter in response to Specification
F.37/35 for a ‘cannon fighter’ armed with four 20mm guns. The Westland design
emerged as a low-wing monoplane with two Rolls-Royce Peregrine
12-cylinder liquid-cooled Vee engines, each rated at 885hp. The
four Hispano Mk I guns were grouped in the nose, while the pilot
enjoyed a good all-round view from a fully-enclosed cockpit
in line with the wing trailing edge. Construction was of metal
throughout, with flush-riveted stressed skins, a novelty being
the use of magnesium rather than aluminium sheet to cover the
monocoque fuselage aft of the cockpit. The first of two prototypes
flew on 11 October 1938, but the Air Ministry lowered a security curtain around
the fighter that was not to be lifted until August 1941. But in reality this
was in vain as drawings of the aircraft had already been published
in France, so there is little doubt that Germany was aware of its
existence and potential.
As the RAF’s first twin-engined fighter, the Whirlwind had
low-altitude performance that was better than that of any
contemporary single-seat fighter and exhibited
excellent handling characteristics, proving to be
very easy to fly at all speeds. The only exception
was the inadequate directional control during
take off that necessitated an increased rudder
area above the tailplane. With a top speed of
over 360mph, it offered a potent combination
of speed and firepower, but it had an Achilles heel.
Problems in the supply of Peregrine engines caused
the first deliveries of Whirlwind I fighters (to No 263
Squadron), to be delayed until July 1940 and
even then it only received eight examples
by year’s end. It was to be another 11
months before the second (and only other)
squadron to be equipped with the Whirlwind
(No 137) became operational at Charmy Down.
The Whirlwind proved a match for German
fighters at low level, as demonstrated on 6 August 1941,
when four Whirlwinds on an anti-shipping strike were
intercepted by a large formation of Messerschmitt
Bf 109s, and claimed three destroyed for no losses.
However, as the performance of the Peregrine
engines fell off at altitude, the Whirlwind was

Westland Whirlwind


Right: Streamlined and powerful, the Whirlwind
promised great things and could achieve
speeds in excess of 360mph, while carrying
a potent punch of four nose-mounted
cannons. However, its performance
dropped off at altitude, where it became
no match for single-seat fighters.
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