Keywords: IAF, HAL, Bangalore, HT-2, HPT-32, HTT-34, HTT-40, Basic Trainer

Introduction

The Indian Air Force (IAF) has a proud legacy of undertaking basic flight training in South India. IAF air bases and training establishments located in the region, have made it the ‘cradle’ of military flight training in India. Since Independence, the IAF’s requirements for basic trainer aircraft have also aided in the growth of aeronautical manufacturing in Southern India. Since 1948, a total of three indigenous basic trainer aircraft, the HT-2, HPT-32 and more recently, the HTT-40 have been developed and manufactured in India. While the latter two basic trainers were vitally important in the growth of India’s nascent domestic aeronautical design and development capability, the completion of design and development of the HTT-40 signals the maturity of the nation’s domestic aerospace and defence ecosystem, which is today producing fighter aircraft, trainer aircraft, utility and attack helicopters. The deliveries of the HTT-40 to the IAF are now slated to begin in Q1 2026.

As we strive towards the goal of ‘Atmanirbhar Bharat’ and self-sufficiency in defence production, it is important to note that the IAF, from 1948 till now, continues to drive the growth of India’s aeronautical industry and will continue to do so.

This is the second of a 3-part-series on indigenously developed basic trainers for the Indian Air Force

PART 2

Piston Pioneer

Following in the footsteps of the HT-2, in 1975 HAL began preliminary work on the development of a new basic trainer for the IAF. The Government sanctioned the design and development of a new basic trainer aircraft in 1976 at a cost of INR 5.53 crores. The requirement was for a total of 161 trainer aircraft and work was proceeding in earnest by 1977.

The design of the Hindustan Piston Trainer 32 (HPT-32). proceeded swiftly, with the first 1st HPT-32 prototype (X 2157) making its maiden flight in Bangalore on 6^th January 1977, piloted by Wg Cdr Inder Chopra, HAL’s Chief Test Pilot (CTP). The second HPT-32 prototype made its maiden flight in March 1979, incorporating several modifications. The third and last prototype made its maiden flight on 31^st July 1981 and was representative of the final production version and significantly lighter than the first two prototypes.[1]

The HPT-32 is a cantilever, low-wing monoplane and of all-metal construction. Unlike the HT-2, the HPT-32 was a nose wheel aircraft with side-by-side seating for two persons under a rearward sliding jettisonable framed canopy. The HPT-32 also had the provision for a seat behind the instructor and trainee, along with space for some luggage. This was due to the fact that HAL had also planned to offer the aircraft to undertake liaison roles. The aircraft had a non-retractable tricycle type landing gear. The aircraft was powered by a Textron Lycoming AEIO-540-D4B5 flat-six 260 hp engine, driving a Hartzell two-blade constant-speed metal propeller. Fatigue life was quoted as 6.500 hours.

The IAF went on to place an initial production order for the new basic trainer in 1981, ordering 40 aircraft with an additional requirement for 100-150. At the time, the cost of each aircraft was estimated at INR 19.25 lakh.[2]

The HPT-32 was inducted into the Indian Air Force in March 1984. The trainer aircraft was used for Stage 1 flight training providing pupils with 65AIAF hours of flying.

HAL completed the delivery of 40 HPT-32s by March 1987. Just as it was with the HT-2, the Navy also acquired the HPT-32, ordering nine aircraft. INAS 550-B Flt at Kochi which was equipped with Islander aircraft in 1976, went on to induct the HPT-32 in January 1986. The squadron completed basic flying training on the HPT-32 in October 1987, for the first batch of six naval pilots. However, training on the HPT-32 was discontinued soon after, and the squadron ceased further basic flying training on the type.[3]

The IAF placed three additional orders for the HPT-32 in August 1988, January 1990 and March 1992 for 40, 30 and 24 additional aircraft respectively. In total, the IAF placed orders for 134 HPT-32s.

A turboprop version of the HPT-32, called as the HTT-34 took to the air for the first time on 17^th June 1984 piloted by Wg Cdr Ashok and another pilot. “The aim was to enhance its performance, while also overcoming the nagging supply problems of high-octane fuel. A turboprop engine uses turbine fuel (refined kerosene). “The more powerful engine on the HTT-34 gave the aircraft excellent performance,” Wg Cdr P Ashoka (retd)” said in his autobiography.[4] HTT-34 prototype was in fact the HPT-32 third prototype which was modified.[5]

However, despite the HTT-34s improved performance, HAL never received any orders for it.

The HTT-34 was also demonstrated as a trainer aircraft at the Farnborough (UK) and Paris Airshows in 1984 and 1985 respectively. “Later we (HAL) took it to Nigeria and Ghana in Africa on a marketing mission. Our aerobatic displays were greatly appreciated and some of the foreign pilots who flew the aircraft, were also duly impressed. Unfortunately, this did not result in any sales, probably for financial reasons,” Wg Cdr Ashoka added.[6]

Troubled Trainer

The HPT-32 took over the basic training role (Phase I) in the IAF in entirety from 1988 onwards, following the retirement of the HT-2.[7]According to a CAG report released in 2019, the HPT-32 aircraft was besieged with difficulties related to reliability and safety including engine failure, poor glide characteristics and absence of an ejection seat.

Due to a large number of accidents, the entire HPT-32 fleet was grounded in July 2009.[8] This decision followed the crash of an HPT-32 on 28^th July 2009 due to engine failure.[9]

A High-Power Study Team (HPST) was constituted by Air HQ and HAL’s Transport Aircraft Division in Jul 2009 to undertake an in-depth analysis of maintainability and reliability of HPT-32 aircraft and its engine. The HPST was tasked to undertake technical investigation to find out the cause of engine failures and suggest remedial measures

However, in August 2009, the IAF decided to discontinue flying of the HPT-32 fleet till the finalization of HPST report. The HPST report released in December 2009 stated that the HPT-32 aircraft was designed and developed in the early 1980s and did not meet present day standards (at the time). The technical investigation carried out by HAL was inconclusive in its findings.

As per a CAG report released in 2013, it observed that engine cut-off issues had resulted in 189 incidents/accidents on HPT-32 aircraft. Originally slated for retirement in 2014, the HPT-32 fleet was grounded in 2009 and resulted in HAL’s HJT-16 Kiran Intermediate Jet Trainer (IJT) being used for Stage I training from 2010 to 2013. In June 2012, the IAF opted not to return its HPT-32 fleet back into service, which at the time numbered approximately 116 aircraft.[10] [11]

In total when combining the HT-2 and HPT-32, 300 trainers were produced by HAL. The HPT-32 remained in service only for 25 years as compared to the HT-2, which remained in service for 34 years. Despite the trials and tribulations with the development of indigenous basic trainers, it would not be out of place, to say that the HT-2 and HPT-32 set the stage for the development of a new, modern and state-of-the-art basic trainer for the future.

A Unique Experience of Flying the HT-2, HPT-32 and HTT-40

Air Chief Marshal V.R. Chaudhari (retd) was commissioned into the Indian Air Force in December 1982 and has the unique distinction of having flown the HT-2, HPT-32 and HTT-40.

I joined the National Defence Academy (NDA) on 15 January 1979 and passed out from the NDA in December 1981. We reported to what was then called Elementary Flying School (EFS) at Bidar on 1 January 1982. Bidar at the time was the home base for the HT-2. The HT-2 was based only in two locations, Bidar and FIS Tambaram. It never flew in Dundigal, which had the T-6 Harvard and later the Kiran Intermediate Jet Trainer (IJT). We underwent a brief one-week orientation course, getting our flying clothing and so on. In the second week of January, we started flying. At EFS Bidar, we also had ground school. This was ground training and primarily about seven to eight subjects, all aviation related. We had a little bit of exposure to all these subjects in the final term in NDA. So it was building up on the basics that we were taught there on aerodynamics and navigation and avionics and aviation medicine and meteorology.

Prior to us joining EFS Bidar and a year earlier, the HT-2 fleet there had experienced a spate of accidents. I cannot recollect the numbers but there were several fatal accidents. As a result, the decision was taken not to allow solo flying in the HT-2, instead our course would have what was then called Dual-cum-Solo (Dolo). This meant that we had a safety pilot in the rear  during our ‘Solo’ sorties. The instructor would not provide any guidance or handle the controls but acted as a safety pilot in the rear seat. We were the first batch at EFS Bidar to perform Dolo sorties. I flew 30.5 hours on the HT-2, which included all types of sorties including general handling, aerobatics and getting a feel of the aircraft. There was no night flying on the HT-2 at that time. If I recollect correctly – and going by my logbook – my 21^st sortie was the solo check clearance for going solo. I never flew the HT-2 solo but instead flew 4-5 Dolo sorties.

I have an anecdote to narrate here on the HT-2 which was a tail wheel aircraft. The tail wheel was held by two strong springs on either side to allow it to caster. So, when one landed the aircraft, it was important to touch down on the two main wheels. There were occasions however, when the aircraft would actually swing from side-to-side because of non-centering of the tail wheel. It could happen for many reasons; drift while landing, a strong cross wind or incorrect rudder inputs. When we applied the rudders the tail wheel also used to move along with the rudder. On the first day when our course started flying, we had two cases of HT-2s swinging on landing, with our entire course all lined up along the runway and in the ATC watching our first few course mates taking to the air.

The HT-2 was a very tricky aircraft to fly and we had quite a lot of attrition during basic flying training in our time. In our course along with 30 cadets from the army and from the air force (NDA and direct entry) we had 78-79 cadets. If I recall correctly when we left Bidar, only 65-70 of us remained in total. Only about 53 passed out from the Air Force Academy (AFA) eventually. Prior to flying the HT-2, I had only done some gliding at NDA and so flying a powered aircraft was a completely alien experience. But I adapted quite easily and quite well.

I have another interesting anecdote on the HT-2. In the cockpit the RT channel change box was on the right side. There were only four preset channels on the RT, so after take-off we had to change from the ATC frequency to the radar frequency. This involved just a change of RT channel, which required one knob selection. But for that the pilot had to take off his right hand from the stick and move the RT knob. This meant that the aircraft had to be trimmed very accurately, otherwise it would start pitching up or going down. So this emerged as a major challenge to most of my course mates.

The other aspect was that the HT-2 did not have an ejection seat. So in case something went wrong with the aircraft, we would have to bail out. There was no time to jettison the canopy also, so part of the downwind checks before coming in for landing was to open the canopy. It was a sliding canopy and when we had it open had the wind on our faces and that was a great experience while landing.

Taxying the HT-2 on ground was another experience, because you just could not see over the aircraft nose, due to the angle. So while taxying we did what was called a ‘snake taxying’ procedure, where we would weave from left to right. So, when you weave off the center line, go to the right and from the left side, now you see that the path ahead is clear. Then you weave to the left and then look over your right and see that the path is clear. It was certainly interesting but if one had the basic psychomotor skills, not so difficult after all.

I recall that the Cirrus Major engine was very reliable and there were not many cases of engine cuts and things like that. Though, yes, the occasional one was there, like in our course, also we had maybe one or two. But I think that was par for the course in those days. Being a tail-dragger aircraft, for take-off when we reached a speed of 55 knots or something like that, we had to push the stick forward to lift the tail wheel up first and then only when we were flying on the main wheels, we would rotate the aircraft by pulling back on the stick.

I have some recollections here from my diary. I had written on my first air experience sortie which took place in January 1982. In fact, I wrote that it was not as exciting as my first sortie in a glider! After my second sortie on the HT-2, I noted that “I must try one more cushion at the back.” We had to carry our own parachutes and seat cushions. On my third sortie I did aerobatics for the first time and noted that after the instructor demonstrated aerobatics, I did two loops, two barrel rolls and one roll, followed by stall turns. I noted that I had no issues with G forces.

We flew one sortie a day, which would be approximately 50-60 minutes duration. The HT-2 could stay in the air for even longer. We also used to do a running change-over on the aircraft. The instructor would remain strapped in the aircraft for three sorties, and the cadets would swap during the running change-over.

From Bidar, we went to the Air Force Academy (AFA) in Dundigal. The HAL Kiran Mk-1As were just entering service at that time. At the time the course consisted of about 30 hours on the HT-2, followed by 80 hours on the Kiran Mk-1A.

I was commissioned into the fighter stream of the IAF in December 1982 and moved to Hakimpet. As of December 1982, I had 116 hours total on the Kiran and the HT-2 put together at AFA. Here I flew the Polish Iskara IJT. Those of us who flew the Iskara went to fly MiG-21, MiG-23 and so on. I flew about 106 hours in the Iskara in day sorties with another eight hours of night flying.  Coming back to the Kiran Mk-1A which was an indigenously developed jet trainer, it was certainly better to fly as it was a little faster, but it had its own minor idiosyncrasies. I would say, each aircraft has some peculiarities, accuracy in flying for example on the Kiran was challenging due to its wing design and high-lift devices. Maintaining accurate speeds or other parameters during manoeuvres was quite a challenge. So, as an example, if I just do a 360 degree turn, maintaining height within a few feet was very difficult on the Kiran.

In summary, the HT-2 was a very good basic trainer aircraft; it took a lot of beating while being operated by young cadets and served the nation for 34 years. It did what was asked of it, no doubt about that.

HPT-32 ‘Deepak’

In 1990, I was sent for the Flying Instructors course to Tambaram. Ours was the first batch which started training on the HPT-32 and this was in June 1990. The batches previous to us had flown the HT-2. We also had to fly the Kiran IJTs so we did half the course on the Kiran and half the course on the HPT-32.

The HPT-32 had several peculiarities; it had very poor glide characteristics. For an aircraft with a not very reliable engine, at least its glide characteristics should have been half as good (at least) as the Kiran or HT-2. If we had an engine failure in the Kiran, we could still glide and make it to the nearest airfield.  The HPT-32 just came down rapidly and had very poor glide characteristics. So, one needed to be on the ball all the time. When you have an aircraft which does not have an ejection seat and bad flight characteristics, safety lies in altitude. So, the higher we flew, the safer we felt. But unfortunately, the HPT-32 didn’t have a very good climb performance, it took forever to climb.

We were flying absolutely brand-new HPT-32s, they were still being maintained by HAL not only at Tambaram but even in AFA. In our time we didn’t have so many engine cuts and that began many years later. The problem with bringing down the aircraft safely following an engine-cut was that the Deccan plateau is a rocky area, so it was challenging to find a flat piece of land. To bail out from the HPT-32, we had to get out of the aircraft and walk on the wing and then jump-off.

In its later years, the HPT-32 fleet engine cut-offs while in the air was too frequent and was a little too high for comfort.

The HPT-32 was also very different from the HT-2 due to having a nose wheel and dual-seating. I am afraid that the HPT-32 did not have too many positives. One of the positives, however, was that the side-by-seating for pilot and instructor, The latter could watch the cadets flying habits closely, this was of-course not possible in a tandem-seat trainer like the HT-2. Apart from this, the HPT-32 had good flying endurance, and we could have running-changeovers here too. Its avionics and flying instruments were a generation ahead of the Kiran Mk-1A.

The Kiran on the other hand, had very benign spin characteristics so when we put it in a spin, we could actually demonstrate something to the cadet and tell him about the nose down angle, how fast the aircraft is spinning, count the turns, etc. The HPT-32 spun so rapidly that it didn’t give time for instructing, we could do post-sortie debrief. The HPT-32 was a huge difference from the Kiran, which had very care-free handling.

I later flew the HPT-32 again as an instructor at AFA and then as an Air Force examiner and accumulated around 270 hours on the type. In comparison to the HPT-32, the HT-2 served the IAF well even though it was a very rudimentary aircraft. It definitely honed our skills in basic flying and for its age and vintage it was a good aeroplane that sufficed for our requirements.

The HPT-32 could have been a much better designed aircraft and should have served the IAF as long as the HT-2 or the Kiran. The design aspects required improvement. Like I said, the glide ratio, the spin characteristics, the power to weight ratio, poor climb performance, and so on. All this could have been much better. With the power of hindsight, I can say that HAL should have looked at a design that was little more futuristic even for a basic trainer. The HPT-32 entered service in the nineties and could have featured better avionics, an ejection seat, capability to teach somebody instrument landing procedures which occupies so much time on fighter aircraft. There were quite a few aspects on the HPT-32 which were lacking for a basic trainer in the nineties, and it was a design that was not ahead of its time.

HTT-40

In addition to flying the HT-2 and the HPT-32, I also s an opportunity to fly a prototype of the HTT-40. There of course will be a difference between a prototype aero plane and the aircraft which eventually enters serial production. The prototype HTT-40 which I flew was a little heavier than the PC-7 MKII and it had modern avionics. The cockpit comfort was very good and the aircraft had ejection seats. Its engine is also quite reliable. I did not undertake any manoeuvres or aerobatics nor did I fly the aircraft to the extremities of its envelope.

My Time with the HT-2

Air Marshal Anil Khosla retired from the Indian Air Force as Vice Chief of the Air Staff. He was commissioned into the Indian Air Force in December 1979.

My very first impression of the HT-2 as a cadet was that it looked simple and almost modest, yet purposeful. As a young flight cadet in the Indian Air Force during the early 1970s, my first encounter with the HT-2 was both exhilarating and a bit intimidating. The aircraft was a sleek, all-metal design with tandem seating and it was simple yet robust. The controls were responsive, but it demanded precision right from the start; a sloppy approach could lead to a bumpy landing on those narrow landing gear.

In total I flew a total of 215 hours on the HT-2. This included 40 hours of ab-initio training, 65 hours during the Flying Instructors’ Course, and 110 hours during instructing at Flying Instructors School (FIS) Tambaram. At FIS Tambaram I instructed on the HT-2 teaching young IAF pilots how to become instructors.

My abiding memories are vivid and multifaceted. I remember the distinctive sound of the engine starting up. I Remember the smell of gasoline during stall turns. One unforgettable sortie for me, was my second solo flight, during which, after take-off, I had an engine failure and had to force-land the aircraft.

The HT-2 was considered challenging to fly, however, it had many attributes that made it such a long-serving basic trainer in the Air Force. The HT-2 earned its reputation as challenging aircraft to fly as it tended to swing on the ground on landing. It required total concentration and focus to prevent over-controlling, especially in crosswinds.  It was known to be somewhat unforgiving if mishandled, especially in the stall/spin regime.

Yet, these very challenges made it an excellent trainer for basic flying skills. It remained in service for over three decades (from the 1950s until the late 1980s), with over 120 aircraft produced.

Its attributes included: –

• • Rugged airframe.

  • Easy to maintain (indigenously available spare parts).

  • Excellent visibility from the front cockpit.

  • Low operating costs.

  • Indigenous production with no dependency on foreign suppliers.

 The aspects of the HT-2 that I liked and disliked were many.

Likes:

• • Handling and Stability—perfect for building confidence in novices.

  • The response to controls was direct, making it great for learning coordination.

  • The bubble canopy and raised instructor’s seat provided panoramic views.

  • The engine was smooth and powerful enough for basic aerobatics.

  • Execution of aerobatic manoeuvres gave a lot of satisfaction and a boost to the confidence level.

Dislikes:

• • The narrow-track undercarriage made landings tricky as it was prone to swinging on the ground.

  • The seats weren’t the most ergonomic for extended sessions, causing back aches during prolonged flying.

  • The seat was fixed without height or position adjustment.

The parachute strapped to the pilot was not very comfortable or easy to bail out.

*****

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Notes:

[1] Global Security Org, “content” https://www.globalsecurity.org/military/world/india/hpt-32.htm accessed on August 25, 2025

[2] Vijay Seth, The Flying Machines of the Indian Air Force 1933 – 1999  (New Delhi: Seth Communications, 2000), p. 41,

[3] Indian Navy NIC, “content” https://indiannavy.gov.in/content/dorniers-2

[4] Wg Cdr P Ashoka, Riding the Wind (New Delhi: Viji Books, 2011), p. 140.

[5] Vayu Aerospace Review 1984

[6] ibid

[7] Performance Audit Report of the Comptroller and Auditor General of India on Capital Acquisition in Indian Air Force, Report No. 3 of 2019

[8] Performance Audit Report of the Comptroller and Auditor General of India on Capital Acquisition in Indian Air Force, Report No. 3 of 2019

[9]  PIB.GOV.IN, “content”, https://www.pib.gov.in/newsite/PrintRelease.aspx?relid=75579&reg=3&lang=2 accessed on Oct 1, 2025.

[10]  Audit Report of the Comptroller and Auditor General of India on Capital Acquisition in Indian Air Force, Audit Report No. 34 of 2014

[11] Performance Audit Report of the Comptroller and Auditor General of India on Capital Acquisition in Indian Air Force, 2017

The post A History of Partnership: The Indian Air Force and Growth of Indigenous Basic Trainer Production in South India appeared first on CAPSS India.

Keywords: IAF, HAL, Bangalore, HTT-40, Basic Trainer

Introduction

The Indian Air Force (IAF) has a proud legacy of undertaking basic flight training in South India. IAF air bases and training establishments located in the region have made it the ‘cradle’ of military flight training in India. Since Independence, the IAF’s requirements for basic trainer aircraft have aided the growth of aeronautical manufacturing in Southern India. Since 1948, a total of three indigenous basic trainer aircraft, the HT-2, HPT-32 and more recently, the HTT-40, have been developed and manufactured in India. While the latter two basic trainers were vitally important in the growth of India’s nascent domestic aeronautical design and development capability, the completion of design and development of the HTT-40 signals the maturity of the nation’s domestic aerospace and defence ecosystem, which is today producing fighter aircraft, trainer aircraft, utility and attack helicopters. The first HTT-40 is now slated to be delivered to the IAF in 2026.

As we strive towards the goal of ‘Atmanirbhar Bharat’ and self-sufficiency in defence production, it is important to note that the IAF, from 1948 till now, continues to drive the growth of India’s aeronautical industry and will continue to do so

This is the final part of a 3-part series on indigenously developed basic trainers for the Indian Air Force

PART III

Milestone Moment

Hindustan Aeronautics Limited (HAL) is to begin deliveries of the indigenously designed and developed Hindustan Turbo Trainer 40 (HTT-40) to the IAF in the first half of 2026. The commencement of deliveries of a new domestic basic trainer will mark an important milestone in India’s history of domestically developed military aircraft. The HTT-40 has been entirely designed, developed, and flight tested by HAL, following in the footsteps of the Hindustan Trainer 2 (HT-2) and the Hindustan Piston Trainer 32 (HPT-32) Deepak. The commencement of HTT-40 deliveries will be a milestone moment for the IAF and India’s aerospace and defence ecosystem, which has come together to once again deliver an indigenous BTA, as in years past with the HT-2 and HPT-32.

Training Need

The induction of the HTT-40 Basic Trainer Aircraft (BTA) will be a much-needed boost to the IAF, which has a longstanding requirement for 181 such aircraft. This need was partially met with the induction of 75 Swiss Pilatus PC-7 Mk II BTAs, introduced into service between February 2013 and November 2015. The HTT-40 will operate alongside the PC-7 MkII in the Stage I basic flying training role.

The HTT-40 will be used for basic flight training, aerobatics, instrument flying, close formation flight training, navigation and night flying. HAL also has plans for a future weaponised variant intended for weapons training, Counterinsurgency (COIN) and limited strike missions. This variant will have four pylons for carrying weapons and other stores, and could also be fitted with a Head Up Display (HUD). The tandem-seat turboprop basic trainer is also a fully aerobatic aircraft.

The IAF has played a pioneering role in the use of simulators for training, and HAL will deliver several synthetic training aids for the HTT-40, including a Fixed Base Full mission Simulator (FBFMS), Cockpit Procedure Trainer (CPT) and Avionics Part Task Trainer (APTT). It is expected that 30 per cent of the training on the HTT-40 will be met through synthetic training.

The IAF had earlier acquired two FBFMS, three CPTs and one APTT for its PC-7 MKII fleet.

Origins

In 2009, the Ministry of Defence (MoD) had decided that the IAF’s BTA requirement for 181 aircraft would be met with 75 trainers to be imported and 106 of an indigenously developed type. The IAF opted for the Swiss Pilatus PC-7 MKII in May 2012 to meet its urgent need for Stage 1 BTA. All 75 aircraft ordered were delivered by 2015. An options clause for 38 additional PC-7 MKIIs was cleared by the DAC in March 2015, but orders were never placed.

The IAF originally issued its Preliminary Staff Qualitative Requirement (PSQR) for the HTT-40 in 2009. The Acceptance of Necessity (AoN) for a new indigenously designed and developed BTA was accorded by the Defence Acquisition Council (DAC) in February 2010. At the time, HAL was to have completed the maiden flight of the HTT-40 by February 2013, obtained certification by 2015, and begun deliveries by 2017. HAL began design and development work on the HTT-40 in earnest from August 2013, when it decided to proceed with the programme using internal funding. Company funds worth INR 177 crore were sanctioned by HAL to undertake the Preliminary Design Phase (PDP) and Detailed Design Phase (DDP) activities of the HTT-40 at the Aircraft Research & Design Centre (AERDC) in Bengaluru.

The first HTT-40 prototype (PT-1) made its maiden flight in Bengaluru on May 31, 2016, and the trainer’s first public flight took place in Bengaluru on June 17, 2016, in the presence of then Defence Minister, the late Dr Manohar Parrikar. During his visit, he made the first official announcement that additional HTT-40s would be procured and that further import of basic trainer aircraft would be capped.[1] At the time, he had stated that the total number of BTAs required would increase from 181 to 210. The second HTT-40 prototype (PT-2) took to the air in June 2022. To reduce the effort required during User Evaluation Trials (UET), a team of test pilots from ASTE were deputed for User Assisted Technical Trials (UATT). Pilots from the IAF’s Aircraft and Systems Testing Establishment (ASTE) also flew sorties for assessing cockpit ergonomics, performance and handling, including stall, prior to the commencement of UETs.[2]

Certification from the Centre for Military Airworthiness and Certification (CEMILAC) was obtained in February 2025.

The delays in the HTT-40 programme can be attributed to several reasons, including the excessive weight of the prototype aircraft, obsolescence of the Engine Electronic Controller (EEC) on the Honeywell TPE331-12B turboprop engine powering the aircraft, and COVID-19.[3] HAL had issued a Request for Proposal (RFP) for a turboprop engine for the HTT-40 in June 2012 and selected the TPE331-12B turboprop engine in June 2015.[4]

                                    HAL HTT-40 Original Delivery Schedule

HAL finally awarded Honeywell a contract worth over USD100 million in July 2021 for 88 TPE331-12B engines/kits along with maintenance and support services. The engines will be assembled under license from Honeywell at HAL’s Engine Division in Bengaluru and maintenance infrastructure for the engine will also be created in India.

HAL had initially proposed to the IAF that initial Limited Series Production aircraft to be delivered would be powered by CAT-B engines, which were originally with the UK Royal Air Force (RAF). These engines were available to HAL after completion of full major overhaul with life restored back to 100 per cent (10,000 hours). [5] They were later to be replaced by brand-new engines and the CAT-B engines would be retained as spares.

The two flying prototypes of the HTT-40 are powered by CAT-B engines.

One of the other important but protracted phases in the development of the HTT-40 was spin trials. Six-turn spin (RHS and LHS) capability was successfully demonstrated towards the end of 2019, followed by eight-turn spin capability in 2020. HAL also benefited from consultations with Office National d’Etudes et de Recherches Aérospatiales (ONERA) of France, which suggested the incorporation of a ventral fin to aid spin trials. ONERA had been contracted by HAL to undertake rotary balance wind tunnel tests for HTT-40 spin trials.^[6]

According to a former HAL official involved in the design and development of the HTT-40, the flying characteristics of the HTT-40 are comparable to the Kiran jet trainer. He stated that HAL test pilots were happy with the HTT-40’s docile handling qualities, with the stall behaviour and maneuvrability being good. There is a high level of commonality between equipment fitted on the HTT-40 and what is used on LCA ‘Tejas’, HJT-36 IJT, ALH, LUH and Dornier Do-228. The Landing Gear and Cockpit Canopy were designed and fabricated by HAL.

Delivering on a Promise

The Defence Acquisition Council (DAC), led by Defence Minister Rajnath Singh, approved[7] the procurement of 106 HTT-40 aircraft on August 11, 2020. At that time, the Ministry of Defence (MoD) had stated that post certification of the HTT-40, 70 aircraft would be procured initially from HAL, with a balance of 36 aircraft to be procured after the trainer was operationalised by the IAF. HAL announced in February 2021 at the Aero India airshow that it had received a Request for Proposal (RFP) from the IAF for 70 HTT-40 trainers with provision for 38 additional aircraft.[8]

The RFP was issued five years after the maiden flight of the first HTT-40 prototype in May 2016. HAL was awarded the contract for 70 HTT-40s in October 2022, worth approximately INR 6,828 Crore.^[9] The HTT-40 will be manufactured at two production lines established by Hindustan Aeronautics at its Aircraft Division, Bengaluru and Aircraft Manufacturing Division, Nasik, with the bulk of production to be undertaken at the latter facility. HAL has stated plans to attain a peak production rate of 20 HTT-40s per annum.

The second HTT-40 production line at HAL’s Nashik facility was formally inaugurated by Defence Minister Rajnath Singh on October 17, 2025. The assembly complex houses structural assembly shops for the manufacture of HTT-40 fuselages, wings and control surfaces.^[x]

While deliveries of the HTT-40 were planned to begin in September 2025, the IAF is now likely to receive its first aircraft in 2026. Deliveries of all 70 aircraft are to be completed by HAL by March 2030.

Training Impact

The IAF has one of the largest requirements in the Indo-Pacific region for trained pilots, navigators and weapon systems officers. Over two decades ago, the air force had planned to train 220 pilots annually during 2001-05; however, as per information provided by the Ministry of Defence (MoD) to the Parliamentary Standing Committee, there was a shortfall ranging from 15 to 31 per cent. A decade later, in February 2015, the IAF assessed that it had a shortage of 486 pilots. At that time, the air force had proposed to increase the number of trainees from 260 to 350 pilots every year by 2017.

A 2024 Report of the Comptroller and Auditor General of India on Training of Pilots in Indian Air Force presented in Parliament in December 2024 stated that “between the period 2016 to 2021, against the planned initial intake of 222 trainees annually, the initial annual intake ranged between 158 and 204 trainees. Also, the annual intake after wastage ranged between 124 and 167. As a result, the shortage of pilots rose from 486 to 596, which was expected to be filled up between January 2021 and January 2030,” the CAG report informed.

The IAF has a pressing need to have its requirement for 181 basic trainers fulfilled, but this has been impacted by the delay in deliveries of the HTT-40.  The IAF’s Stage I requirement will only be fully met when induction of all 108 HTT-40s is complete, joining the present fleet of 74 PC-7 MK IIs.

New Age Trainer

The HTT-40 is fitted with a state-of-the-art glass cockpit and modern avionics and can attain a maximum speed of 450 kilometres per hour, along with a maximum service ceiling of six kilometres. The HTT-40 is powered by a single Honeywell TPE331-12B turboprop engine fitted with a four-blade lightweight Hartzell aluminium propeller. TPE 331-5 turboprop engines have been produced at HAL since 1988, and its engine division is also an authorised service centre for TPE331-5 to –12 series engines.

Each aircraft features two Martin-Baker Mk16 Zero-Zero ejection seats. There are over 1,000 Martin-Baker Seats already in service in the IAF and Indian Navy. The aircraft also features indigenously developed avionics for radio communication, standby communication, VOR-ILS, TACAN, Radio Altimeter, Identification Friend or Foe (IFF) and Integrated Standby Instrument System (ISIS).

The HTT-40 has a glide ratio of 12:1 and a maximum load factor +6/-3 G. HAL quotes a Maximum Take-Off Weight (MTOW) of 3,040 kg with 460 kg of internal fuel. However, the normal training weight of the aircraft will be 2,800 kg. The time to climb to three km is quoted at 7.05 minutes, while the service ceiling is six km. The aircraft will have a maximum range of just over1,000 km and a maximum endurance of four hours.

The HTT-40 is capable of hot-refuelling, which allows the aircraft to be refuelled with the engine running. It is also capable of undertaking a running change, where, with the engine running, the propellers can be put into reverse, changing the blade angle. This results in no rotor downwash, allowing the canopy to be opened and the next cadet to strap into the aircraft. The HTT-40 flight test crew have rated cockpit visibility, crew comfort and the Environmental Control System as excellent. During conducted hot weather trials at Nashik, the cockpit temperature was maintained at a comfortable 25 °C as against an outside air temperature of 47 °C.

The HTT-40 features a largely all-metal construction and makes limited use of composites. HAL has put in extensive effort to ensure that the aircraft is easily maintainable, with the aim of achieving a high daily sortie rate along with high flight line availability. The indigenously developed BTAs are expected to fly 300 hours annually and will have a Total Technical Life (TTL) of 10,000 hours/30 years. HAL aims to deliver a 1200-hour Time Between Overhaul (TBO).^[11]

Development of indigenous military platforms has substantially spun off to the local industry. The HTT-40 is expected to have an indigenous content of 56 per cent for the initial aircraft produced, and this will progressively increase to over 60 per cent over the course of the programme through indigenisation of major components and subsystems. The HTT-40 programme could eventually provide direct employment to approximately 1,500 personnel, along with indirect employment for up to 3,000 people spread over more than 100 MSMEs.

Training Day

Basic Flight Training is the bedrock of IAF training for its pilots and aircrew, and the induction of the HTT-40 into service will provide a much-needed boost in BTA numbers for the IAF. The IAF is rapidly inducting new fighter aircraft, transport aircraft and helicopters, and the availability of sufficient numbers of trained pilots and aircrew is vitally important.

The HTT-40 marks the return of an indigenously developed BTA into the air force, and this is very welcome indeed. Hindustan Aeronautics will need to ensure that it delivers the promised aircraft on time, with high standards of quality, and is well supported in terms of maintenance and spare parts. The imminent induction of the HTT-40 into IAF service marks a new chapter for India’s military aviation and self-reliance and continues the legacy of the HT-2 and HPT-32.

*****

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Notes:

[1] Atul Chandra, “https://www.flightglobal.com/india-taps-locally-made-htt-40-as-next-basic-trainer/120919.article”, Flight Global, June 21, 2016. Accessed on December 20, 2025.

[2] Mr R Madhavan, HAL CMD in Q&A with author, 10-29-2020.

[3] Mr. Prashant Singh Bhadoria, Project Manager for HTT 40 in Q&A with author 11-30-2020

[4] Show News, https://aviationweek.com/shownews/paris-airshow/honeywell-provide-engines-hal-made-indian-training-aircraft, Aviation Week, June 17, 2015, Accessed on December 20, 2025.

[5] Mr. Prashant Singh Bhadoria, Project Manager for HTT 40 in Q&A with author 11-30-2020

^[6] Atul Chandra, “India’s Homegrown Trainer” Air Forces Monthly January 2021, p.85

[7] Press information Bureau, Government of India, “DAC approves procurement proposals worth Rs 8,722.38 crore, including 106 Basic Trainer Aircraft for IAF,” August 11, 2020, https://www.pib.gov.in/PressReleaseIframePage.aspx?PRID=1645092&reg=3&lang=2. Accessed on December 20, 2025.

[8] Press Information Bureau, Government of India, “ HAL receives Request for Proposal for 70 HTT-40 Basic Trainer Aircraft from Indian Air Force at Aero India 2021,” February 04, 2021, https://www.pib.gov.in/Pressreleaseshare.aspx?PRID=1695163&reg=3&lang=2. Accessed on December 20, 2025.

^[9] Press Information Bureau, Government of India. “Union Cabinet approves procurement of 70 HTT-40 Basic Trainer Aircraft from HAL for Indian Air Force at a cost of over Rs 6,800 crore,” March 01, 2023,  https://www.pib.gov.in/PressReleasePage.aspx?PRID=1903445&reg=3&lang=2. Accessed on September 1, 2025.

^[10] Press Information Bureau, Government of India, “Flight of self-reliance: Raksha Mantri inaugurates 3rd Production Line of LCA Mk1A & 2nd Production Line of HTT-40 at HAL Nashik,” October 17, 2025, https://www.pib.gov.in/PressReleasePage.aspx?PRID=2180339&reg=3&lang=1. Accessed on October 17, 2025.

^[11] CAPSS research visit to HAL, August 2025.

The post A History of Partnership: The Indian Air Force and the Growth of Indigenous Basic Trainer Production in South India appeared first on CAPSS India.

Keywords: IAF, HAL, HT-2, HPT-32, HTT-34, HTT-40, Basic Trainer

Introduction

The Indian Air Force (IAF) has a proud legacy of undertaking basic flight training in South India. IAF air bases and training establishments located in the region have made it the ‘cradle’ of military flight training in India. Since Independence, the IAF’s requirements for basic trainer aircraft have also aided in the growth of aeronautical manufacturing in Southern India. Since 1948, a total of three indigenous basic trainer aircraft, the HT-2, HPT-32 and more recently, the HTT-40, have been developed and manufactured in India. While the latter two basic trainers were vitally important in the growth of India’s nascent domestic aeronautical design and development capability, the completion of design and development of the HTT-40 signals the maturity of the nation’s domestic aerospace and defence ecosystem, which is today producing fighter aircraft, trainer aircraft, utility and attack helicopters. The first HTT-40 is slated to be delivered to the IAF this September

As we strive towards the goal of ‘Atmanirbhar Bharat’ and self-sufficiency in defence production, it is important to note that the IAF has driven the growth of India’s aeronautical industry since 1948 and will continue to do so.

This is part one of a three-part series on indigenously developed basic trainers for the Indian Air Force.

PART 1

Early Days

Hindustan Aeronautics Limited (HAL) as we know it today was originally registered by Seth Walchand Hirachand as Hindustan Aircraft Limited under the Mysore Companies Act on December 23, 1940. The work on India’s first aircraft factory formally commenced on January 12, 1941, when the foundation stone was laid for HAL’s Bangalore factory. The fledgling Hindustan Aircraft Limited assembled its first aircraft, a Harlow trainer, which flew within eight months of the company’s registration. The first local orders for aircraft production in India were awarded to HAL for assembly under license of 20 Harlow PC-5 trainers, 48 Curtiss 75A-SP Hawk fighters and 74 Vultee V-12-D attack bombers, to aid the WW II effort. [1]

By December 1942, control of Hindustan Aircraft was ceded to the United States (US) Tenth Air Force for the duration of World War II. [2] Following the end of World War II, the control of Hindustan Aircraft reverted to the Government of India in December 1945. [3] Bangalore was selected over Barrackpore and Poona to be the hub of aircraft manufacture in post-Independence India, as it was only at Hindustan Aircraft’s factories that the whole process of building an aircraft from semi-finished material had been undertaken, prior to Independence. [4]

Importantly, post-Independence, HAL immediately began the overhaul and reconstruction of approximately 150 Tiger Moth basic trainers and wartime residual Harvard advanced trainers. [5] This was crucial in allowing the IAF to begin elementary flying training immediately after Independence. HAL’s first license-produced aircraft after Independence was also a trainer aircraft, the Percival P.40 Prentice. The Prentice was developed to meet the Royal Air Force’s (RAF) requirement for a basic trainer aircraft to replace the Tiger Moth. A total of 375 units of this type were delivered to the RAF, with Argentina, India, and Lebanon being its other customers. [6] The Prentice was the RAF’s first side-by-side trainer and was also unique in that a second student could be accommodated in the rear cockpit to observe the instructor and student pilot in front!

To meet the IAF’s urgent need for a basic trainer aircraft, HAL produced sixty-five P.40 Prentice under license in just over a year. [7] The first Indian assembled Prentice made its maiden flight with HAL’s CTP Capt Jimmy Munshi at the controls on April 30, 1948. [8]

Note: Hindustan Aeronautics Limited (HAL) was formed on October 1, 1964, as the amalgamation of two companies, i.e. Hindustan Aircraft Limited and Aeronautics India Limited (created for license-production of the MiG-21 aircraft under license).

On a Wing and a Prayer

During 1947-48, discussions were held on the type of aircraft that would be designed for the first time in India. The IAF requirement for a basic trainer aircraft was accepted, and the Government of India sanctioned the development of such a type on October 11, 1948, which would also be used by flying clubs. It is interesting to note that the original plans called for three indigenous trainer aircraft types to be developed: the Hindustan Trainer 2 (HT-2) primary trainer, HT-10 advanced trainer, and HT-11 intermediate trainer. [9] However, the latter two never progressed beyond the mockup stage.

In any event, work proceeded swiftly on the HT-2 and its full-scale mockup was ready by August 1949, less than a year from programme sanction. The first HT-2 prototype (VT-DFW) made its maiden flight on August 5, 1951, and the second prototype (VT-DCG) took to the air for the first time on February 19, 1952. In a landmark moment for Indian aviation, the HT-2 received its Type Certificate on January 3, 1953, and was formally inducted into the IAF on January 10, 1955. [10]

The HT-2 replaced the long-serving Tiger Moth and initially operated alongside the Prentice.

In 1955, the indigenous trainer type was inducted into the Flight Instructors School at Tambaram and No.2 Air Force Academy, Begumpet, with pupils logging 40 hours on the aircraft before proceeding to the Harvard. The HT-2 was used to train cadets of No. 68 Pilot Instruction Course in 1955, and by the time of the 72^nd Course, the indigenous trainer had replaced the Prentice entirely. [11]

An all-metal piston-engine basic trainer, the HT-2 was powered by a 155-HP Cirrus Major III four-cylinder air-cooled piston engine with a two-blade fixed-pitch propeller. It could attain a maximum speed of 209 kmph. It had a range of 560 km and a service ceiling of 14,500 feet. Flight endurance was just under four hours.

In his autobiography ‘Riding the Wind’, Wing Commander P Ashoka provides an insight into the HT-2. “It was a tail wheel aircraft, requiring just that much greater attention during take-off and landing. It had conventional manual flight controls and an elevator trim tab. The controls were well harmonised and pleasant to feel. Though quite underpowered, it was still a fully aerobatic machine.” [12]

The HT-2 also served with the Indian Navy for a short period, less than a decade, during which three aircraft were operated for ab-initio flying training. The Navy’s first Fleet Requirement Unit (FRU) was commissioned on May 11, 1953, at Venduruthy II, Kochi and recommissioned as INAS 550 on June 15, 1959. The HT-2 was inducted into the FRU in October 1956 and phased out of service by 1964. [13] HAL ceased production of the HT-2 in 1958 after manufacturing approximately 166 aircraft, out of which 150 were delivered to the air force.

The HT-2 was later also re-engined in the mid-eighties with the Avco Lycoming AEIO-320-D2B engine, receiving the designation HT-2L. Limited numbers of HT-2s were re-engined and operated by the Flying Instructor’s School (FIS) at AFS Tambaram. [14]  The last of the HT-2s were finally retired from service in 1989.  According to one estimate, over 5,500 air force, army and navy pilots trained on the HT-2. [15]

In the final analysis, the HT-2, as India’s first indigenous aircraft and one specifically designed for the IAF, can undoubtedly be considered a success. According to Hindustan Aeronautics Limited, a total of 169 HT-2s were produced. [16] The HT-2s with the IAF served the nation for 34 years and helped not only solidify the foundation of IAF flight training but also that of aircraft manufacturing in India.

Overseas Sojourn

The HT-2 was also the first Indian designed and developed military aircraft to be exported. This was no small feat for newly independent India, and it remains the only indigenously developed fixed-wing military aircraft exported by India. Ghana acquired 12 aircraft, which it operated from 1959 to 1974. The Air Force deputed Wing Commander LM Katre (later CAS and CMD, HAL) to convert a few Ghanaian instructors on the type. [17]

It is interesting to note, however, that at least two of the Ghanaian aircraft, following their retirement from service, made their way to South Africa and were later offered for sale as restoration projects.[18] The HT-2 also made it as far afield as Australia with two demonstrator aircraft (VT-DIJ and VT-DJQ/VH-AWL) flying in-country from 1957-1960. Two aircraft were also sent to Singapore and Indonesia.

One of the HT-2s (VH-AWL) imported to Australia undertook a demonstration tour in June 1958, where the aircraft flown by Flt Lt Sunandan Roy, a HAL test pilot, demonstrated the type to the Royal Australian Air Force (RAAF) and several flying clubs in Sydney, New South Wales, Melbourne, Victoria, Adelaide, South Australia and Brisbane, Queensland.  One of the aerobatic demonstrations involved an eight-turn spin followed by low-level cloverleaf loops, with steep turns and slow rolls in a reciprocal direction. [19]

However, during a demonstration in Brisbane that same year, an aircraft impacted the ground, sustaining extensive damage and injuring the pilot. The aircraft was returned to India, but by the time a replacement aircraft arrived in Australia and conducted a sales tour, Royal Air Force (RAF) surplus Chipmunks were available to aero clubs, and the HT-2 received no orders. This aircraft was later returned to India and did not receive an Australian registration. [10]

INTERVIEW: Air Commodore KA Muthanna (Retd).

Air Commodore KA Muthanna retired as Chief of Test Flying (Fixed Wing) at Hindustan Aeronautics Limited. He was commissioned into the Indian Air Force in June 1981.

I passed out of NDA in 1980, and in the second half of that year. I was to fly the HT-2 as a cadet in the No. 127 Pilots Course. We were all wide-eyed at the sight of the first powered aircraft that we would fly. There was excitement, apprehension, and some of us felt overwhelmed. At that stage, we had no knowledge of how to pilot this aircraft, as we had never flown a powered aircraft before.

After passing out of NDA, we went to Bidar and did the Maintenance Conversion Flight (MCF) on the HT-2. This was basically where we did ground training on the HT-2. Thereafter, we went to Dundigal and conducted dual-check sorties, which involved around eight instruction sorties. The HT-2 was a tail-wheel aircraft, yeah, so the first impression you had while sitting in the cockpit was that only you could see the sky! We could not see anything in front of us. As a result, while taxying out on the runway, I had to weave around the centreline and look out from the side of the cockpit to see where I was going. Also, when taking off on the HT-2, you had to push the stick forward to raise the tail wheel, then pull it back for liftoff.

In total, I must have flown around 40 hours on the HT-2 during my six months of basic training. Our course was also the last, in which cadets would get to fly this aircraft solo. Somewhere halfway through our course, or not even halfway (at least, definitely after I went solo), we had a fatal accident. One of the cadets stalled the aircraft while turning onto finals and went into the ground. Due to this and their history with the type, they stopped cadets from flying solo on this aircraft, and thereafter they only flew something called Dolo, which meant having an instructor sitting quietly behind.

My instructor was not too happy with my landing on my first solo flight.  On the HT-2, during the final approach, we had to perform a ‘round-off’. So, when we were about a foot or so off the runway, we had to drop the aircraft on the runway, so that it wouldn’t swing on landing, something the HT-2 was very prone to do.  Hence, it was mandated that, when coming in for landing, if the pilot was not happy with his height at which he ‘rounded off’ (this is known as a flare in a jet aircraft), then he had to go around and attempt the landing again. What I did was open the throttle, let the aircraft descend a little more, then close it and land! My instructor was not happy!

Later, when I moved on to the Kiran Intermediate Jet Trainer as part of my training, I realised that the faster Kiran was easier to fly than the HT-2.

Interestingly, six years later, I got to fly the HT-2 again, this time while doing my trainee instructor course at the Flying Instructors School (FIS) in Tambaram. We had to fly both the HT-2 and the Kiran equally, and this time we had to fly the HT-2 from the rear cockpit. Now, since many of us had done fighter flying, we were walking with a swagger, but the HT-2 brought us back down to Mother Earth! Frontal visibility, which was always poor on the HT-2, was even worse when in the rear seat with another pilot in front of you!

I did another 20 hours on the HT-2 and never flew it again for the rest of my career. When you consider that the HT-2 was developed just a few years after the end of World War II, we can certainly consider it a good design and an aircraft that served the air force well and for a long time.

*****

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Notes:

[1] Air Commodore Jasjit Singh, Indian Aircraft Industry (New Delhi: KW Publishers, 2011), p. 45.

[2] Ibid., p.52.

[3] Ibid., p.52.

[4] Ibid., p.52.

[5] Ibid., p.52.

[6] “Digital Archive,” International Bomber Command Centre Digital Archive, https://ibccdigitalarchive.lincoln.ac.uk/files/original/1371/23293/PThomasAF20080027.2.jpg. Accessed on August 18, 2025.

[7] Ibid., p.110.

[8] Ibid., p.110.

[9] Ibid., p.111.

[10] Ibid., p.114.

[11] Kapil Bhargava, “HT-2 – India’s First Powered Aircraft,” Bharat Rakshak, November 30, 1999,  https://www.bharat-rakshak.com/iaf/aircraft/past/hal-ht2/. Accessed on June 22, 2025

[12] Wing Commander P Ashoka, Riding the Wind (New Delhi: Viji Books, 2011), p. 130.

[13] Indian Navy, “Dorniers,” https://indiannavy.gov.in/content/dorniers-2. Accessed on July 07, 2025.

[14] “HAL HT-2 [IX480],” Warbirds of India, November 25, 2008, https://www.warbirds.in/karnataka/bangalore/hal/hal-ht-2-ix480. Accessed on July 10, 2025.

[15] Vijay Seth, The Flying Machines of the Indian Air Force 1933–1999 (New Delhi: Seth Communications, 2000), p. 41.

[16] Author’s research visit to Hindustan Aeronautics Limited.

[17] Bharat Rakshak, n. 11.

[18] David C Eyere, “Hindustan HT-2,” Aeropedia, August 25, 2019, https://aeropedia.com.au/content/hindustan-ht-2/. Accessed on June 25, 2025.

[19] Ibid.

[20]  Ibid.

The post A History of Partnership: The Indian Air Force and Growth of Indigenous Basic Trainer Production in South India appeared first on CAPSS India.