The HPT-32 is a fully aerobatic piston engined basic trainer, with side by side seats for instructor and pupil. It can be used for a wide range of ab initio training, including instrument, navigation, night flying and formation flying; for armed patrol; for observation, liaison or sport flying; or for weapon training, light strike duties, supply dropping, search and rescue, reconnaissance, or glider or target towing. The all-metal airframe is designed to FAR Pt 23.
The first prototype (X2157) made its initial flight on 6 January 1977. The third, flown on 31 July 1981, represented the production version, substantially lighter in weight and with aerodynamic refinements. By 31 March 1987 a total of 40 had been delivered to the Indian Air Force and eight to the Indian Navy. An IAF follow-on order for 30 has been placed, production of which began in late 1987 or early 1988.
TYPE: Two-seat ab initio, aerobatic, night flying, instrument flying and navigation trainer.
WINGS: Cantilever low-wing monoplane. Wing section NACA 64A1-212. Dihedral 5° from roots. Incidence 2° 30' at root. No sweepback. Light alloy safe-life wings, of tapered planform, with stressed skin. Light alloy plain ailerons and plain trailing-edge flaps. Balance tab in, and ground adjustable tab on, each aileron. Pitot static tube can be heated.
FUSELAGE: Semi-monocoque safe-life structure of light alloy, with stressed skin.
TAIL UNIT: Cantilever light alloy stressed skin structure, with sweptback vertical surfaces. One-piece elevator. Trim tabs in rudder and starboard half of elevator; balance tabs in rudder and port half of elevator.
LANDING GEAR: Non-retractable tricycle type, with HAL oleo-pneumatic shock absorber in each unit. Dunlop UK single mainwheels and nosewheel. Dunlop UK mainwheel tyres, size 446 x 151 x 166 mm, pressure 3.10 bars (45 lb/sq in); Dunlop India nosewheel tyre, size 361 x 126 x 127 mm, pressure 2.41 bars (35 lb/sq in). Dunlop UK aircooled hydraulic disc brakes on mainwheels.
POWER PLANT: One 194 kW (260 hp) Textron Lycoming AEIO-540-D4B5 flat-six engine, driving a Hartzell two-blade constant-speed metal propeller. Total of 220 litres (58.1 US gallons; 48.4 Imp gallons) of fuel in four flexible tanks (two in each wing), plus a 9 litre (2.4 US gallon; 2 Imp gallon) metal collector tank in fuselage. Total fuel capacity 229 litres (60.5 US gallons; 50.4 Imp gallons) Overwing refuelling points. Oil capacity 13.6 litres (3.6 US gallons; 3 Imp gallons).
ACCOMMODATION: Side by side seats for two persons under rearward sliding jettisonable framed canopy. Seats adjustable in height by 127 mm (5 in). Full dual controls, and adjustable rudder pedals, for instructor and pupil. Cockpit ventilated.
SYSTEMS: Hydraulic system for brakes only. Electrical system (28V DC earth return type) powered by 70A alternator, with SAFT 24V nickel-cadmium standby battery. No air-conditioning, pneumatic, de-icing or oxygen systems.
AVIONICS: HAL (Hyderabad Divn) COM-150 main UHF and COM-104A standby VHF com; directional gyro. No blind-flying instrumentation.