New Delhi: Honeywell Aerospace expects to deliver four additional TPE331-12B turboprop engines to Hindustan Aeronautics Limited (HAL) by the end of 2026, a move expected to support production of India’s indigenous HTT-40 basic trainer aircraft for the Indian Air Force (IAF).
The planned shipment will take Honeywell’s direct engine deliveries to HAL this year to eight. The supplies form part of a $100 million contract signed in July 2022 for 88 engines, covering both direct deliveries and the progressive transfer of manufacturing capabilities to India.
Under the agreement, Honeywell is supplying the initial batches, while HAL is expected to assemble the remaining engines domestically through a technology transfer arrangement.
The HTT-40 programme has faced delays due to supply chain disruptions. A fire at a subcontractor’s facility reportedly damaged manufacturing capacity for two critical engine components, forcing Honeywell to identify alternative suppliers. HAL had earlier targeted delivery of 12 aircraft during the 2025–26 financial year but missed the deadline amid the engine supply delays.
Progress has since resumed, with HAL delivering the first three HTT-40 trainer aircraft to the IAF in September 2026. The Ministry of Defence placed an order for 70 aircraft in March 2023 under a contract valued at approximately ₹6,828 crore.
Known as “Ankur” in IAF service, the tandem-seat HTT-40 is designed to provide Stage 1 basic flight training to trainee pilots and replace the retired HPT-32 Deepak trainer fleet.
HAL is manufacturing the aircraft at production facilities in Bengaluru and Nashik, with the objective of delivering all 70 trainers by March 2030. The arrival of the next four engines by December is expected to help maintain the aircraft assembly schedule.
The TPE331 engine family also has an established presence in Indian aviation, powering the Dornier 228 utility aircraft operated by the IAF and other government agencies. Existing experience with the engine family could help support maintenance and servicing of the HTT-40 fleet as it enters wider operational service.
