On June 20, 2014, Air Chief Marshal Arup Raha, Chief of the Air Staff (CAS) while on a visit to the Air Force Academy (AFA) at Dundigal near Hyderabad to review the passing out parade, flew a sortie in the Pilatus PC-7 MkII basic trainer aircraft, 75 of which have been procured for the Indian Air Force (IAF) with induction beginning in July 2013. Not only was the sortie flown by the CAS an event of glory and prestige for the premier flying training institution of the IAF, for the CAS himself the event was of immense significance but for an entirely different reason. It was 41 years ago in July 1973 that Flight Cadet Arup Raha after graduating from the National Defence Academy where he was awarded the President’s Gold Medal for standing first in the overall order of merit, joined the Elementary Flying School (EFS) then located at Air Force Station Bidar in northern Karnataka. At EFS Bidar, Flight Cadet Arup Raha flew the basic trainer, the HT-2, designed and built by the Indian aerospace major the Hindustan Aeronautics Limited (HAL). For the CAS, on June 20, 2014, it was indeed a red-letter day as for him, life had indeed come a full circle in the last over four decades with the IAF!

Basic Trainers in the IAF

The HT-2 and the Pilatus PC-7 MkII are both single engine aircraft designed, developed and produced for basic military flying training. But this is where the comparison ends. The HT-2 was a two-seat, single-engine tail-wheel aircraft with tandem seating arrangement and was powered by a 155 horsepower Cirrus Major III piston engine. With this engine, the aircraft was capable of attaining a maximum speed of 185 kmph. The Pilatus PC-7 MkII is also a two-seat, singleengine aircraft again with tandem seating arrangement for the crew. It was designed, developed and manufactured by Pilatus Aircraft of Switzerland. Compared with the HT-2, the Pilatus PC-7 MkII is a nose-wheel aircraft and has a much higher level of performance as this basic trainer is powered by a single Pratt & Whitney Canada PT6A turboprop engine capable of delivering 550 shaft horsepower. The aircraft has a maximum cruise speed of 412 kmph and a never exceed speed of 500 kmph.

The fleet of HT-2 basic trainer aircraft that had served the IAF since the mid-1950s was phased out in 1989 following a case of structural failure in flight. A highly experienced instructor and an under training flying instructor perished in the crash. The basic trainer HT-2 was replaced by the HPT-32, a single piston engine aircraft with side by side seating, also developed by HAL. One and a half decades later, the HPT-32 fleet was permanently grounded by the IAF in July 2009 on account of a series of engine failures in flight, the final one resulting in the tragic loss of two experienced flying instructors. The high rate of engine shut down in flight on the HPT-32 that took the life of 20 young pilots, reportedly was attributable to an inherent design flaw in the fuel supply system that despite considerable effort, HAL was unable to resolve.

With the somewhat premature grounding of the HPT-32 fleet, the IAF suddenly found itself without a basic trainer. As HAL had not even begun planning a replacement of the HPT-32 fleet, on its part it had no ready solution to offer. Left high and dry literally, the predicament the IAF was in, was indeed serious. Air Headquarters therefore had no option but to explore the global market for a fast track solution.

Enter the Pilatus PC-7 MkII

In June 2011, through a global tender, the IAF selected the Pilatus PC-7 MkII as the preferred platform for the basic stage (Stage I) training of its pilots. The Pilatus PC-7 aircraft is fully aerobatic and is capable of undertaking all basic training exercises both by day and night including instrument and tactical flying. The aircraft in its different versions is operated by more than 20 air forces for ab initio training. Since its introduction in 1978, close to 500 aircraft have been sold. The global fleet having clocked over one million hours, most of the aircraft delivered by the company continue in service today.

The IAF placed an initial order for 75 Pilatus PC-7 MkII aircraft. The contract was signed on May 24, 2012, and the first aircraft arrived at the AFA in February 2013, its debut in the IAF coinciding with Aero India 2013. All 75 aircraft ordered so far are scheduled to be delivered by early 2015 and given the track record of the original equipment manufacturer (OEM) Pilatus Aircraft of Switzerland, there should be no doubt about the time lines declared by the company.

As for performance, experience of the IAF in operating the Pilatus PC-7 fleet at AFA indicates that the aircraft has high reliability, requires low maintenance, has excellent serviceability and very high availability on the flight line generating high sortie rate. The performance of the Pilatus fleet during the last 18 months of operation at AFA has inspired the IAF to plan for enhanced intake of the number of trainees and increase the basic training syllabus in terms of flight hours in step with the growth in fleet size.

Given the criticality and the urgency of the need to build up a the basic trainer fleet to the desired level, the most expedient option for the IAF would have been to procure off the shelf another 106 Pilatus aircraft. However, on account of the competing requirement to also focus on strengthening the domestic aerospace industry in accordance with the Defence Procurement Procedure 2013, this proposal did not find favour with the government. The next best and a viable option would have been production of the aircraft in the country under licence following the acquisition of the first batch of 75. Although licensed production has been HAL’s forte since the days of the MiG-21, in the case of the Pilatus PC-7 MkII, for some reason, HAL categorically rejected the proposal and insisted on pursuing their own programme to design and build 106 Hindustan Turbo Trainer 40 (HTT-40) aircraft to augment the trainer fleet of the IAF. In view of the track record of HAL in the development of original designs such as the Tejas light combat aircraft, the IAF would never be certain about the timeframe for delivery of the new HTT-40, a situation clearly untenable for the service. Besides, having two different types of aircraft in the basic trainer fleet would generate its own set of problems and hence is an option best avoided by the IAF.

While the search for a way forward is yet to be found, it is understood that orders for a second batch of 37 aircraft have been placed on the OEM taking the total number to be procured directly from the Swiss manufacturer to 112. However, procurement of the remaining 69 aircraft continues to be a plagued with a degree of uncertainty. However, the IAF has now come up with a solution hitherto not even thought of. The IAF has in the recent past sent a proposal to the Ministry of Defence to manufacture the aircraft under licence at its Base Repair Depot (BRD) in Sulur near Coimbatore. Over the years, the 16 BRDs in the IAF have grown and matured enough to undertake licensed production of even combat aircraft. Licensed production of the Pilatus PC-7 MkII should therefore be well within their capability. Besides, the IAF will be able to exercise control over production, something that cannot do with HAL.