Indian state-owned aircraft manufacturer, Hindustan Aeronautics Limited (HAL) has commenced spin flight testing of its modified HJT-36 Intermediate Jet Trainer (IJT).
The aircraft was indigenously designed and developed by HAL to replace the ageing Kiran aircraft fleet of the Indian Air Force (IAF).
The flight was piloted by HAL’s test pilots Group Captain H.V. Thakur (Retd) and Wing Commander P. Avasti (Retd). The spin testing of an aircraft is the most crucial phase of its flight testing. Accordingly, the testing will be gradually progressed to assess the behavior of the aircraft till six turn spins to either side to meet the targeted requirement.
The IJT has already been tested to its full envelope in terms of speed altitude and load factor (‘g’ envelope) and has also been integrated with drop tanks as well as bombs.
For spin test, HAL redesigned the aircraft by moving the vertical tail aft and extending the rudder surface. These changes for ensuring a satisfactory spin behavior required extensive redesign of the rear fuselage and the rudder. The changes have been incorporated in two aircraft with the involvement and clearance from certification agencies at every stage. Post modification, the two aircraft underwent significant flight tests to assess the general handling with the new configuration of fin and rudder. These aircraft have now been incorporated with the necessary safety devices (Anti-Spin Parachute Systems). During the first flight, initially the aircraft was taken through one tum spin to the left and right hand sides to test the spin characteristics.
HAL HJT-36 Sitara
HAL HJT-36 Sitara (“Star”) is a subsonic intermediate jet trainer aircraft being developed by Hindustan Aeronautics Limited (HAL) for the Indian Air Force to replace the service’s HAL HJT-16 Kiran fleet for the Stage II training of its pilots.
The Sitara is a conventional jet trainer with low swept wings, tandem cockpit and small air intakes for the engine on either side of its fuselage.
IJT will be fitted with AL-55i turbofan jet engines produced in house at Engine Division Koraput. IJT incorporates the simplicity necessary for ease of conversion from Basic Piston Trainer and the sophistication required for quick conversion to the complexities of an Advanced Jet Trainer.