How will HAL's HTT-40 help in pilot training for new IAF inductees?

The news about the approval for procurement of 70 HTT-40 basic trainer aircraft from Hindustan Aeronautics Limited (HAL) is indeed a reason for cheer for the Indian Air Force. This aircraft will be supplied over a period of six years, and the procurement would cost around Rs 6,828 crore.

The trainer aircraft will be used by the IAF for fundamental flight training, aerobatics, instrument flying, and close formation flights, as well as for navigation and night flying.

The HTT-40 was awarded the airworthiness certificate in mid- 2022, six years after its inaugural flight.

The HTT-40 has been certified to comply with Preliminary Staff Qualitative Requirements and Federal Aviation Regulation 23 standards following a design evaluation, aircraft systems tests, and flight tests involving HAL and IAF pilots. The approval came from the Centre for Military Airworthiness and Certification, which is part of the Defence Research and Development Organisation (DRDO).

HAL has reported that the tandem-seat HTT-40 has a take-off weight of 2,800kg, a top speed of 450km per hour and a range of 1,000km. The aircraft is operated by a Honeywell TPE-331-12B turboprop engine, with an electronic controller, pressurised fuel system, dual hydraulics, and a glide ratio of 13:1.

“The HTT-40 has air-conditioned cockpits, advanced avionics and hot refueling capabilities, as well as zero-zero ejection seats, which operate at zero altitudes and zero airspeeds. This turbo trainer is fully aerobatic and features a tandem seat. The HTT-40's predecessor, the HPT-32, was afflicted with engine and fuel supply issues, which generated accidents and multiple pilot fatalities. Consequently, the IAF acquired a fleet of 75 Pilatus PC-7 Mk II trainers in 2009 after the HPT-32 was grounded,” Girish Linganna, a defence and aerospace expert and the Director of ADD Engineering Components (India) Limited, told THE WEEK.

As per market sources, HAL has invested $85 million in the design and development of the HTT-40, comprising the production of two prototypes and a minimum of 550 flight tests. As per the Ministry of Defence, the acquisition of the aircraft will assist the Indian Air Force in addressing the current deficit of basic trainer aircraft for pilot training for new inductees. HAL will deliver 70 HTT-40 aircraft, their associated equipment and necessary training aids, such as simulators, over a span of six years.

“The HTT-40 programme is supported by a supply chain of over one hundred domestic, private small-scale enterprises, providing 1,500 direct and 3,000 indirect job opportunities through local suppliers. Pilots of the IAF will begin their training with flight instruction on these aircraft. During the next two stages, the pilots are educated in operating the Kiran Mark II jet and Hawk advanced jet, respectively,” added Linganna.

Interestingly the 70 HTT is presently composed of 56 per cent Indian-made systems and components, which is expected to increase to 60 per cent. The HTT-40 will be offered to international customers at a cost of approximately $7 million per unit, according to market sources. Hindustan Aeronautics Limited (HAL) will be constructing the trainer at its facilities in Bengaluru and Nashik, having designed and developed the aircraft.

“The HTT-40 demonstrated superior performance compared to the Pilatus and fulfilled the IAF's performance criteria. During testing, the HTT-40 exceeded the IAF's requirement for top speed of 400 km per hour, reaching 420 km per hour. Additionally, it surpassed the IAF's ceiling requirement of 20,000 feet, achieving 20,200 feet. Furthermore, it requires 800 metres of runway for take-off and landing, which is below the 1,000 metre limit set by the IAF in its Preliminary Staff Qualitative Requirement. HTT-40 also cleared the "six-turn spin test" later,” explained Linganna.