The Folland Gnat is a British compact swept-wing subsonic fighter aircraft.
Private-venture prototype fighter, one built.
Single seat lightweight fighter exported to Finland, India and Yugoslavia, 50 built by Folland at Hamble.
This was also built in India under licence as the HAL Gnat.
One aircraft for Finland was built with three nose-mounted 70mm Vinten cameras and designated FR.1, it was joined by a Ministry of Supply aircraft purchased by Folland and modified to the same standard.
Both aircraft were delivered to Finland on 12 October 1960.
Fo.142 Gnat / Gnat F.2
This was to be an improved F.1 using a wing with a 6% thickness-to-chord ratio and powered by a Bristol Orpheus with simplified reheat (BOr.12SR), developing 8000 lbF (35.6 kN) thrust.
A prototype wing was built but not mated to a fuselage or engine.
It was anticipated that this would be capable of Mach 1.5 and have a “marked increase in rate of climb” development was ended because Bristol declined to back development of the reheat.
Fo.143 Gnat / Gnat F.4
Proposed improved F.2 with air intercept radar and ability to carry guided weapons, not built.
Fo.144 Gnat Trainer / Gnat T.1
Two-seat advanced trainer aircraft for the Royal Air Force, 105 built by Hawker Siddeley.
Proposed development from January 1960, with larger wing (and flap) area.
It was to be powered by two Rolls-Royce RB153 engines with reheat.
The design also considered operation from aircraft carriers.
This was a two-seat design with variable geometry wings based on a combination of the Gnat Mk5 and the Gnat Trainer.
It was to be powered by two Rolls-Royce RB153 engines with reheat and thrust-reversers.
It was to be produced as either an advanced trainer with weapons capability or as a fighter.
This, and later studies were led by Maurice Brennan.
Indian development of the Gnat F.1
HAL Ajeet Trainer
Two-seat tandem trainer version for the Indian Air Force.
This version was derived from the HAL Ajeet and differed considerably from the Gnat T.1 used by the RAF.
29 ft 9 in (9.07 m)
22 ft 2 in (6.76 m)
8 ft 10 in (2.69 m)
136.6 sq ft (12.69 m2)
RAE 102 modified
4,800 lb (2,177 kg)
6,575 lb (2,982 kg) interceptor
8,765 lb (3,976 kg) tactical, with external tanks and armament
Max take-off weight
9,040 lb (4,100 kg)
175 imp gal (210 US gal; 800 l) in seven fuselage tanks
25 imp gal (30 US gal; 110 l) in two optional rear fuselage tanks
Two optional 66 imp gal (79 US gal; 300 l) jettisonable underwing slipper tanks,