Ravi Sharma

BANGALORE: Overcoming numerous integration issues the indigenous intermediate jet trainer (IJT) Hindustan Jet Trainer-36 (HJT-36) presently under development at Hindustan Aeronautics Limited (HAL) has crossed a major milestone making its maiden flight with the Russian AL-551 engine.

Piloted by HAL’s Executive Director Squadron Leader (retd) Baldev Singh and the Indian Air Force’s (IAF’s) Wing Commander K.D. Bhat, the HJT-36’s Prototype One (PT1) undertook a 30 minute flight on May 9 landing without any hitches. However, being the PT1’s maiden flight only general manoeuvres were gone through with, no major checks undertaken.

The flight is of significance since it marks the beginning of the final phase of development of the trainer, which has been under development for a decade. Though two HJT-36 prototypes have so far taken to the skies they are powered by the proven French-made Snecma Larzac 04H20 engine. However HAL in conjunction with the IAF’s air staff requirements had opted for a new and more powerful engine choosing the Russian aircraft engine designer/manufacturer NPO-Saturn, who in turn developed the AL-551 engine.

Last June, though way behind schedule HAL had received a prototype of the AL-55I and integrated it on the PT1. After successfully conducting ground and taxi trials on the ‘yellow banded’ engine (not a fly worthy engine) it was sent back to Russia for flight trials and certification tests. But delays in Russia meant that HAL could not adhere to its schedule of flying the trainer in November with the AL-551 engine. Though the new engine arrived in February HAL was faced with a number of issues during the integration of the engine with the aircraft’s other systems, not least being issues with the throttle control and the various indicators in the cockpit (which prompt the pilot to take corrective action).

Making it worse PT1 was a ‘recovered aircraft’, having recovered from the February 2007 crash (when the canopy inadvertently flew open just prior to take off) and there were numerous certification issues since a number of parts had been changed.

Acknowledging the delays officials on the HJT-36 programme told The Hindu that the trainer’s Initial Operational Clearance could still be obtained by June 2010 since most of the engine integration issues were over. “Since the trainer’s avionics are already in place and it will carry only practice weapons — gun and rocket pods — we don’t see huge delays.”

However one blip is the delay in insurance cover for the aircraft. The Russians are still to pay the premiums and send HAL the required documents.

Meant to become the backbone of the IAF’s basic pilot training programme the IJT programme was sanctioned by the Government in 1999 with an initial budget of Rs. 180 crores. Though it first flew in March 2003 (with the French engine) its flight with the AL-551 has been delayed by over three years. The first HJT-36s were to have been delivered in 2006-07. HAL have an order for 12 Limited Series Production aircraft and a further order for 60 production aircraft.

Around 225 HJT-36s are to be eventually produced, serving the IAF, the Navy as well as the Air Force’s Surya Kiran aerobatic team.