A two seat fighter aircraft taking advantage of the high performance of the Hawker Hart, from which it was developed.
Hawker Demon RAF K4500 An air to air view of RAF Hawker Demon I K4500.

The Hawker Demon was a two-seat fighter derivative of the Hawker Hart day bomber.


Such was the performance of the Hart that it was significantly faster than the RAF’s single seat fighters of the day, such as the Bristol Bulldog.


The Demon was designed against Specification 15/30, which was drawn up around the performance of the existing Hart design by Sydney Camm.


Hawker modified the first production Hart (J9933) to act as a prototype Demon although it was originally known as the Hart Fighter.


The main changes from the Hart were the use of a 560 hp supercharged Rolls-Royce Kestrel V(DR) engine and a downward sloping rear cockpit coaming, which afforded a better field of fire for the rear gunner.


Two fixed forward-fining Vickers machine guns were fitted in troughs on either side of the fuselage. Under-wing racks could be fitted for the carriage of light bombs, when required.


Hawker Demon K2842 1933 A 1933 photograph of RAF Demon I K2842 showing the sloping edge of the rear cockpit aperture.


A first batch of Hart Fighters were supplied to 23 Sqn RAF in May 1931. Production Demon aircraft (to Specification 6/32) were supplied initially with the 485 hp Kestrel IIS with later machines having the 585 hp Kestrel V.


The first production Demon K2842 was first flown on 10th February 1933.


Difficulties with the slipstream affecting the rear gunner resulted in a segmented, hydraulically-operated retractable windshield (built by British Sports Car manufacturers Frazer Nash) being fitted to all later Demons. These aircraft were sometimes known as 'Turret Demons'.


Hawker Demon K8203 hangar G-BTVE is painted in the colours of a 64 Sqn Demon I K8203 and seen at Old Warden.

In addition to use by the RAF, 64 Demon aircraft with a 600 hp Kestrel V(DR) were supplied to the Royal Australian Air Force. These aircraft were used for general purpose, army cooperation and training duties, rather than exclusively as fighters.


They were also equipped with a tailwheel, rather than a tail skid undercarriage.


RAAF Hawker Demon I A1-8 RAAF Hawker Demon I A1-8 is on display at the RAAF Museum, Point Cook, VIC.


A total of 304 Demon were built with this total being made up of 1 Prototype, 6 Hart Fighter, 233 Demon for the RAF, and 64 aircraft for the RAAF. Of the production machines, Hawker built 133 Hart Fighters and Demons for the RAF and a further 64 Demons for the RAAF. The remaining 106 Demon aircraft were built by Boulton Paul Aircraft Ltd.


The type remained in limited service with the RAF after the outbreak of the Second World War, being used for roles including target towing. Similarly, some of the RAAF aircraft saw limited service in communications and training roles.

Variants & Numbers

Hart Fighter One prototype (modified Hart) plus six production Hart Fighter.
Demon I Two-seat fighter aircraft for the RAF. 233 built
Turret Demon Demon I aircraft when fitted with a Frazer Nash ‘lobster-back’ windshield.
Australian Demon I RAAF aircraft: 18 fighter and 36 army cooperation.
Australian Demon II RAAF: 10 additional aircraft for training and target towing duties.
Total 304 aircraft 1 prototype, 6 Hart Fighter, 233 Demon I, 64 RAAF aircraft.


Powerplant One 485 hp Kestrel IIS (RAF), 585 hp Kestrel V(DR) (RAF turret equipped), or 600 hp Kestrel V(DR) (RAAF)
Span 37 ft 2 in
Maximum Weight 4,464 lb (fighter); 4,668 lb (turret equipped); 4,716 lb (RAAF fighter)
Capacity and armament Pilot and gunner, two forward-firing Vickers machine gun plus one Lewis gun fired from rear cockpit. RAAF aircraft: provision for  up to six underwing bomb carriers.
Maximum Speed 182 mph at 13,000 ft (Kestrel IIS); 182 mph at 16,400 ft (Kestrel V(DR))
Endurance / Range 2 hr 30 min


Hawker Demon I (A1-8)  RAAF Museum in Point Cook, VIC. 


Demon I
Painted as K8203 of No. 64 Squadron RAF. The Shuttleworth Collection



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