Aircraft maker Hindustan Aeronautics Limited (HAL) may have delivered the first batch of HTT-40 basic trainers to the Indian Air Force (IAF), out of 70 on order, but a steady supply of engines by US firm Honeywell remains critical to keeping the ₹6,838-crore programme on schedule, officials aware of the matter said.
The aerospace major hopes Honeywell will resolve supply-chain bottlenecks and stabilise TPE331-12B engine deliveries from next year, the officials said.
The IAF ordered 70 basic trainers three years ago to train its rookie pilots. Under the contract, HAL was to deliver 12 trainers to the IAF in fiscal 2025-26 but failed to deliver any aircraft due to an engine shortage. Honeywell, which faced supply chain bottlenecks, began delivering the turboprop engines for the indigenous basic trainer aircraft to HAL a few months ago and assured the firm of timely supplies.
“There is an engine-related issue as Honeywell has tier-1 and tier-2 supply chain issues. The firm has promised us six engines by December. It is looking for alternative sources (to overcome supply chain bottlenecks),” HAL chairman and managing director Ravi K said in an interview.
“The supplies are expected to stabilise from next year. Aircraft production is not an issue; it’s on track,” he told HT. On September 18, HAL handed over three HTT-40 (Hindustan Turbo Trainer-40) planes and two light combat aircraft (LCA Mk-1) trainers to the IAF, along with four Dhruv NG civil helicopters to Pawan Hans Limited.
The HTT-40s will bolster the air force’s capacity to meet its growing pilot training requirements. The basic trainer will serve as a stepping stone for pilots to develop critical flying skills.
Currently, ab initio (Stage-I) flying training of all rookie pilots is carried out on Swiss-origin Pilatus PC-7 MkII basic trainers. Stage-I training is common for all pilots after which trifurcation into fighter, transport and helicopter streams takes place. Those selected for the fighter stream proceed to Stage-II training on PC-7 MkII and Kiran Mk-1A jet trainers and then Stage-III on the British-origin Hawk advanced jet trainers before they can fly supersonic fighter planes. Pilots from the other two streams carry out their Stage II and III training on different types of transport aircraft and helicopters.
Speaking in Bengaluru last week, defence minister Rajnath Singh said India relied on imported aircraft for years to meet its basic training requirements, but HAL is now indigenously manufacturing the HTT-40 to cater to the air force’s needs. He added that the aircraft holds export potential.
Under a $100 million contract signed four years ago for supplying and manufacturing 88 TPE331-12B engines/kits, Honeywell was supposed to deliver the first engine in September 2025. The US firm will supply 16 units and HAL will build the rest through technology transfer.
A new manufacturing facility for the HTT-40s will help accelerate deliveries. Last October, Singh inaugurated production lines for the HTT-40 basic trainer and LCA-Mk1A in Nashik to meet the air force’s needs. HAL can now produce a total of 20 HTT-40s a year at its factories in Bengaluru and Nashik.
The tandem-seat HTT-40 has an air-conditioned cockpit, modern avionics, hot refuelling capability (refuelling with the engine running on the ground), and zero-zero ejection seats (for safe ejection at low speeds and low heights). The HTT-40 currently has 56% local content, which will progressively increase to over 60% through further indigenisation of major components and subsystems.
