Chronic delays in indigenous trainer aircraft have disrupted IAF training pipelines and increased reliance on imports, underscoring the need for a more resilient aviation ecosystem
Militaries worldwide benefit significantly from stable, robust foundational structures. These enable operational efficiency and the optimal use of scarce resources for national security. From an Indian Air Force (IAF) perspective, a weak foundation—particularly in the training of aircrew, who form the cutting edge of the service’s combat capability—entails several risks that can seriously jeopardise both safety and operational effectiveness.
Lost in the noise surrounding several high-profile inductions over the last five decades—from the Jaguar, Mirage-2000, Su-30MKI, LCA (Tejas), Rafale, C-130J Super Hercules, C-17, Chinook, and Apache—the lack of progress in inducting indigenously designed, developed, and manufactured trainer aircraft beyond the HT-2, HPT-32, and HJT-16 Kiran raised questions about the performance of Hindustan Aeronautics Limited (HAL) . Military aircrew training worldwide is largely divided into three stages: basic, intermediate, and advanced. In the IAF, it was previously considered desirable that every trainee pilot undergo a stable, standardised basic and intermediate phase, comprising exposure to both turboprop and jet flying, before being evaluated for aptitude to join one of three streams in the IAF—fighter, transport, or helicopter.
The IAF’s training journey from the early 1960s to 2009 comprised a basic stage based on two indigenous piston-engine trainers, the HT-2 and the HPT-32.
Such a process has existed only in fits and starts over the past five decades—not because of constant policy changes, but because of instability in the availability of indigenous training platforms across the training spectrum. The IAF’s training journey from the early 1960s to 2009 comprised a basic stage based on two indigenous piston-engine trainers, the HT-2 and the HPT-32. Built in the 1950s, the HAL-built Hindustan Trainer-2 served the IAF adequately as a basic trainer until the early 1980s, when it was replaced by another piston-engine aircraft, the HPT-32, which was already behind its time. Unable to meet the IAF’s requirement for a turboprop trainer aircraft, the HPT-32 remained in service for over two decades, plagued by serious maintenance problems.
From 2000 onwards, the IAF repeatedly articulated the need to replace piston-engine trainers with modern turboprop trainers, hoping that HAL would deliver a reasonably modern successor to the HPT-32. However, this remained a pipe dream until the HPT-32 was grounded in 2009 following a series of engine-failure-driven crashes, several of which led to fatalities. In the absence of any available and viable indigenous option, the IAF was forced to conduct basic flying training on the ageing HJT-16 Kiran jet trainer until it found a suitable basic turboprop trainer, an unscientific model not followed by any other air force.
In the absence of adequate indigenous options after 2009, the IAF floated an international tender for 75 basic trainer aircraft. In 2011, following a stringent selection process, the IAF selected the Swiss Pilatus PC-7 turboprop trainer, a contemporary and modern platform used by over two dozen countries. The deal also included an option clause to procure 38 additional aircraft at the same price of around INR 30 crore each.
The IAF, however, remained unconvinced, given that since 1999 it had already committed a significant portion of its budget to HAL for the design and development of the HJT-36, or Sitara Intermediate Jet Trainer — a project intended to replace the HJT-16, which was due to be phased out in 2014.
Prompted into action and advising the Ministry of Defence (MoD) against proceeding with the Pilatus deal, according to senior IAF officers who were involved in negotiation, HAL hastily submitted a proposal to design and develop the HTT-40 using its own funding, with a commitment to deliver the first batch of aircraft within three to four years. The IAF, however, remained unconvinced, given that since 1999 it had already committed a significant portion of its budget to HAL for the design and development of the HJT-36, or Sitara Intermediate Jet Trainer — a project intended to replace the HJT-16, which was due to be phased out in 2014. With the Sitara still nowhere in sight, the IAF was unwilling to risk a similar outcome and what it viewed as a double setback. It therefore pushed through the acquisition of 75 Pilatus aircraft, with induction completed by 2014, nearly five years after the grounding of the HPT-32.
Unfortunately, the IAF was unable to exercise the option clause for 38 additional Pilatus aircraft, which were essential to ensure a single standardised platform for basic training over the next few decades, until HAL developed a next-generation basic trainer aircraft. Consequently, the HAL-designed HTT-40 gained renewed relevance as it was intended to quickly supplement the Pilatus as the IAF’s basic trainer. However, despite its apparent simplicity, the platform has still not entered service, nearly 10 years after HAL’s initial promise. It is now scheduled for initial induction into the Flying Instructors School later this year, with flight cadets likely to begin flying it only next year.
The Hindustan Jet Trainer-16 (HJT-16) is a licensed variant of the 1950s-vintage Jet Provost aircraft, which was phased out of the Royal Air Force in 1993. Inducted into the IAF in 1968 as a more advanced, licensed-manufactured version produced by HAL, the HJT-16—known as the Kiran—served as both a basic and advanced jet trainer for nearly 40 years, until it was replaced in the advanced role by the Hawk in 2006. It continues, however, in its upgraded Mk IA and Mk II variants as a basic jet trainer at flying academies and at the Flying Instructors School.
The British Aerospace Hawk was inducted in 2006, gradually enabling the IAF to dispense with the MiG-21 as its LIFT platform and align with advanced air forces in deploying better-prepared rookie fighter pilots to operational squadrons.
In the absence of an Advanced Jet Trainer (AJT) in the 1980s, the IAF faced the daunting proposition of transitioning rookie fighter pilots directly from an ageing legacy jet trainer (HJT-16) to aircraft such as the Jaguar and MiG-23/27/29 variants. It had no option but to convert the ageing MiG-21—which was not designed for graduated fighter training—into a Lead-in Fighter Trainer (LIFT) role. The IAF remained constrained by this arrangement for over two decades, until another imported platform provided relief. The British Aerospace Hawk was inducted in 2006, gradually enabling the IAF to dispense with the MiG-21 as its LIFT platform and align with advanced air forces in deploying better-prepared rookie fighter pilots to operational squadrons.
One last millstone continues to weigh down IAF—the proposed replacement of the six-decade-old HJT-16 basic jet trainer with the HAL-built Sitara Intermediate Jet Trainer (HJT-36). Having committed over INR 4,000 crore over several years to the design and development of the HJT-36 to meet the requirements of standardised intermediate flying training, the relevance of the aircraft gradually diminished as its planned induction failed to keep pace with the phased de-induction of the HJT-16, which has continued to slip from 2014 to beyond 2026. This has forced the IAF to grant multiple extensions to the ageing Kiran, despite its obsolescence.
One last millstone continues to weigh down IAF—the proposed replacement of the six-decade-old HJT-16 basic jet trainer with the HAL-built Sitara Intermediate Jet Trainer (HJT-36).
As the existing fleet of Kiran aircraft has dwindled, the IAF has managed to sustain only the bare minimum number required to meet the needs of intermediate jet training for pilots selected for the fighter stream. In a modified two-stage training regimen, shaped more by aircraft availability than by design, rookie helicopter and transport pilots are now being routed directly from the Pilatus basic trainer to commence type training on Chetak helicopters and the twin-engine Dornier light transport aircraft. Fortunately, this transition has proven relatively smooth, owing to the strong foundational training provided by the Pilatus PC-7.
Notwithstanding its upgraded glass cockpit, engine modifications, performance enhancements, and renaming from Sitara to Yashas, HAL and the IAF remain at odds over the suitability of the HJT-36, or Intermediate Jet Trainer (IJT), to fill the intermediate flying training slot that will be left vacant once the Kiran is phased out and the IAF transitions to a two-stage training regimen.
While the IAF was earlier amenable to placing an order for 12 Limited Series Production HJT-36 aircraft in 2006, followed by a further 73 aircraft in 2010, it is now reluctant to underwrite a large-scale procurement. Instead, it prefers to ‘evaluate’ the upgraded Yashas as a potential replacement for the Hawk Advanced Jet Trainer before committing additional funds to the programme.
HAL has frequently attributed delays to shifting requirements and changing goalposts during the development phases of both the HTT-40 and the Sitara IJT. However, the inability to deliver a modern trainer aircraft at the lowest tier of the military aviation value chain reflects poorly on the broader ecosystem.
Arjun Subramaniam is a retired Air Vice Marshal of the Indian Air Force and a strategic commentator.
The views expressed above belong to the author(s). ORF research and analyses now available on Telegram! Click here to access our curated content — blogs, longforms and interviews.
Air Vice Marshal (Dr) Arjun Subramaniam (Retd) is a fighter pilot from the Indian Air Force, a military historian, air power analyst, and strategic commentator. ...
Read More +
PREV
