Explainer: Tracing India’s 76-year journey of developing trainer aircraft that has its share of ups & downs

The launch of the Hansa-3 basic trainer aircraft on April 4 is an important milestone in the country’s aviation sector as it is not only the first such aircraft to be designed by a civilian agency but also the first to be manufactured by the private industry. It also focuses attention on the long journey of developing indigenous trainer aircraft that began over 76 years ago and has had its share of ups and downs.

Aircraft production in India so far has been the domain of the public sector under the purview of the Ministry of Defence and dominated by military products like fighters, helicopters, UAV’s and light utility aircraft. Hansa has been developed by the Council for Scientific and Industrial Research (CSIR), an establishment of the Ministry of Science and Technology, with the private industry also now foraying into the industry, especially in the unmanned aerial vehicles segment.

It was in October 1948, a little after Independence, that defence public sector undertaking (DPSU), Hindustan Aeronautics Limited (HAL) received government sanction for the design and development of a basic trainer.

Work on the project began soon thereafter and in a year’s time a mock-up of the aircraft was ready. After some suggestions for improvements by the IAF, the design was finalised in February 1950, with construction process beginning immediately.

The aircraft, christened HT-2, made its first flight in August 1951, with Captain Jamshed Kaikobad Munshi, HAL’s first post-independence Chief Test Pilot, at the controls. The maiden flight lasted about 40 minutes.

The aircraft was a low-wing cantilever monoplane with a fixed tailwheel landing gear and enclosed tandem cockpits with dual controls. Powered by a 155 hp Cirrus Major-III piston engine, it had a top speed of 210 kmph and a range of 560 kms with a flying endurance of three-and-a-half hours.

The HT-2 was inducted into service in 1953 and began replacing the earlier British-origin aircraft, some of which were also licensed-produced by HAL, which traces its establishment to December 1940.

HAL built about 172 of these trainers, which served the Indian Air Force, Indian Navy as well as a few civilian flying training clubs. Twelve aircraft were also exported to the west African nation of Ghana. These were finally retired in 1990 after having buzzed over the Indian skies for 36 years. The airframes of about two dozen aircraft are on display at various air force bases, museums, sainik schools and civilian areas.

HAL’s next indigenous project was the HJT-16 Kiran, an intermediate jet-powered trainer conceived to fill the IAF’s requirements for the second phase, a step above basic training.

The prototype made its maiden flight in September 1964. The first deliveries of the pre-production series were made to the IAF in March 1968 and full-scale production of the type was approved shortly thereafter.

The aircraft was also retrofitted with external underwing hardpoints to carry about 500 kg of ordnance, enabling its use for weapons training and employment as a light attack aircraft. Later variants, designated as Kiran-II, had a more powerful engine.

As many as 190 Kirans were manufactured by HAL till 1989. Besides, trainers for the IAF and the Navy, these also equipped the Surya Kiran and Sagar Pawan, their respective aerobatic display teams, till the role was taken over by the Hawk aircraft.

In the mid-1970s, HAL came up with the HPT-32 Deepak, which was intended to replace the HT-2 for basic training. First flown in January 1977, it however, was not successful. Later, HAL tried to develop an upgraded variant, called HTP-34, with a more powerful engine, but it did not receive any interest from the users.

The aircraft was plagued by engine and fuel line problems, resulting in numerous incidents. After a fatal accident in July 2009, Air Headquarters grounded the entire HPT-32 fleet and the aircraft were withdrawn from service, to be replaced by the Swiss Pilatus PC-7.

To replace the Kiran for intermediate or Stage-II training, jet-engined HJT-36 Sitara was conceived by HAL, and work commenced in 1997. With its first flight in March 2003, it entered limited series production in 2010 but the IAF termed it to be unfit for service due to technological issues related to its flight parameters.

After extensive modifications to resolve technical problems, HJT-36, was renamed as the ‘Yashas’ and unveiled at the Aero India-2025. Problems that had cropped up with the Sitara included departure from controlled flight and issues with critical stall and spin characteristics. Some structural modifications and design changes were also carried out to address the issues.

According to reports, the IAF has so far not placed any orders for the Yashas, but would initially lease four to five aircraft from HAL to assess its operational capabilities, which could take about a year.

In February 2016, HAL rolled out the first prototype of the HTT-40 basic trainer, a replacement for the HTP-32 on which it had been working on since 2013. In 2022, IAF and HAL concluded a contract worth Rs 6,800 crore for 70 HTT-40s. The first aircraft is expected to be delivered in September this year, with HAL projecting a production rate of 20 aircraft per year.

HLFT-42 — a next-generation supersonic trainer jet for advanced combat training — is also on the drawing boards at HAL. The concept was officially unveiled in 2023 and is meant to replace the current BAE Hawk jet trainers in Indian service. Earlier this year, HAL said that it was redesigning the HLFT-42 following certain recommendations from the IAF. This project is an off-shoot of the HJT-39, advanced jet trainer announced in 2005, but later cancelled.

India