The Aircraft Powering IAF's Rescue Missions in Sudan

In a mission lasting 24 hours, the IAF's C-17 which took off from its home base at Hindan, on New Delhi’s outskirts, obtained an additional load of fuel from Jeddah en route, and smoothly transported its load of primarily women and children to Ahmedabad from the Wadi Sayyidna airstrip in Sudan.

The Indian Air Force (IAF) yet again reinforced the efficacy of its newly acquired fleet of US transports, by boldly evacuating 192 Indians from war-torn Sudan aboard one of its Boeing C-17 Globemaster III air lifters on the midnight of May 3-4, and ferrying them back home, non-stop.

In a mission lasting 24 hours, the IAF’s C-17 – part of the 81 ‘Sky Lords’ squadron – which took off from its home base at Hindan, on New Delhi’s outskirts, obtained an additional load of fuel from Jeddah en route, and smoothly transported its load of primarily women and children to Ahmedabad from the Wadi Sayyidna airstrip in Sudan, an IAF statement stated. It further stated that in its landing approach in Sudan, the C-17 had executed an ’overhead steep tactical arrival’ followed by a successful dextrous ‘assault approach’.

The C-17’s engines were kept running during the entire operation in readiness for a speedy exit, should the need have arisen, the statement added. After delivering its evacuee load at Ahmedabad late in the evening on May 4, the transport returned to Hindan, having more than vindicated its squadron’s Sanskrit motto of Saksham, Sabal, Sarvotre (Capable, Powerful and Omnipresent).

Earlier, in late April the IAF had executed a similar mission in pitch darkness, rescuing 121 stranded Indians from the same Wadi Sayyidna airstrip, some 40 km north of the Sudanese capital Khartoum on one of its Lockheed Martin Lockheed C-130J-30 ‘Super Hercules’ transports. On that expedition too, this aircraft more than vindicated its stated capabilities, all of which have been roundly lauded by IAF veterans and analysts.

Writing in The Hindu last week, Air Vice Marshal Manmohan Bahadur (retired) extolled the IAF’s and the Indian leadership’s ‘foresight’ in purchasing the two US-origin transport types in anticipation of the country’s ‘growing stature and responsibilities’. Both the C-130J-30’s and the C-17s, he maintained, were ‘outstanding’ capability enablers that collectively had appreciably enhanced the IAF’s strategic lift competence.

Presently, the IAF operates 11 C-17s, ordered in 2011 and formally inducted into service September 2013 onwards and 12 C-130J-30’s, deliveries of which began in 2011 after the tender for them was inked three years earlier. The latter transports, specially configured for use by the Indian military’s special forces were divided between the 77 ‘Veiled Vipers’ Squadron at Hindan and the 87 ‘Wings of Valour’ Squadron at Panagarh in the east.

Both aircraft were acquired via the Foreign Military Sales (FMS) route, with the C-130J-30s costing around US$2-2.5 billion and the C-17s priced at around US$4.1 billion. In recent times, both platforms had been instrumental in assisting Indian Army personnel and their assorted assets like tanks and infantry combat vehicles (ICVs) deploy along the disputed Line of Actual Control in eastern Ladakh, where it has been locked in an ongoing face-off with China’s People’s Liberation Army.

A history of India’s transport aircraft

The IAF had last acquired some 70-odd second-hand twin-piston engine Fairchild C-119 ‘Flying Boxcars’ in the 1950s, after which New Delhi’s relationship with Washington deteriorated and those with Moscow proliferated, lasting the duration of the Cold War era, which ended only in the early 1990s. The C-119s, however, were retired in the 80s, following their extensive employment in two wars with Pakistan in 1965 and 1971.

Hence, for over five decades thereafter, the IAF remained dependant almost entirely on legacy Soviet-origin transport platforms – in addition to combat aircraft – like the Ilyushin Il-76 ‘Candid’ and Antonov An-32 ‘Cline’, which a cross-section of IAF pilots maintained had recently been ‘technologically outmanoeuvred’ by the newly inducted US transports.

IAF’s Russian transport platforms Ilyushin Il-76 ‘Candid’ and Antonov An-32 ‘Cline’. Photos: Michael Sender/Wikimedia Commons, CC BY-SA 3.0; Toprohan/English Wikipedia, CC BY-SA 3.0 Collage: The Wire

“The fully automated, state-of-the-art flight decks of both US models fitted with +4 generation avionics were far superior to those of the two Soviet transports, making them relatively effortless to operate,” a former IAF transport pilot stated, declining to identified. Besides, the US platforms were ‘significantly’ more fuel efficient, requiring a smaller, three-person crew – two pilots and a loadmaster – to operate, compared to five personnel needed for an Il-76 and four for an An-32, he said.

Other than operating ease both in the air and on ground, the US transports 12-week maintenance cycle was almost three times higher than that of the Il-76s and even the 60-70 retrofitted and upgraded twin-turboprop An-32s, both of which required regular servicing every three-four weeks, stated the abovementioned C-17 pilot.

“The total technical life cycle of C-130J-30 and C-17 engines too is notably higher, almost 10 times more than that of the fuel-intensive Soviet aircraft power packs,” retired Air Marshal V.K. Bhatia said. This operational aspect increased platform efficiency and considerably reduced maintenance and operating costs, he added.

What fuels the advanced performance of US transport platforms?

Another senior IAF transport pilot stated that the fundamental key to the advanced performance of the two US transport platforms was the technological superiority of their propulsion systems: the C-17s four Pratt & Whitney F117-PW-100 turbofan power packs and the C-130J-30s four Rolls-Royce AE 2100D3 turboprop engines, each rated at 4,591 shaft horsepower or 3,425 kW. These engines, he declared augmented both aircrafts’ mission adaptability, by facilitating their ability to operate from ‘austere’ airfields in rough terrain, at high altitudes and in extreme temperatures, but imposing little or no ‘technological penalty’ upon them.

The operational envelope of the Il-76s and An-32s, on the other hand, fitted with four Aviadvigatel PS-90-76 turbofan engines and two ZMKB Progress AI-20DM turboprop power packs respectively, was relatively limited. Besides, the latter needed constant ‘vigil, nurturing, coaxing and careful handling’, the pilot stated, adding that this ‘severely handicapped’ their overall operational availability.

With a cruising speed of 830 kmph, the T-tailed C-17 was capable of delivering over 74 tons of cargo per sortie-almost twice that of the Il-76’s 42-ton payload – or 158 fully equipped military personnel or 102 fully kitted paratroopers to a distance of over 4,200km in varied terrain at all times. Alternately, it can also double as an aerial ambulance, transporting 54 medical casualties or one main battle tank and three ICVs over the same distance.

The C-17, another pilot declared was capable of taking off and landing from un-prepared or partially ready runways, some even as short as 1,064 metres and as narrow as 90 metres; its thrust reversers, on the other hand, can be employed to back the aircraft up and change direction on narrow taxiways using a three-point turn, a competence lacking in the Russian transports.

The aircraft’s heads-up display (HUD) and advanced avionics allowed it to touch down within 40-60 metres of a predetermined point, an operational precision the Il-76 lacked, experts said. The C-130J-30s too were equally, if not more capable of, short-take-offs-and-landings (STOL) from unprepared, rudimentary or makeshift runways.

Additionally, the 36-tonne ‘Super Hercules’ export model which the IAF operated, adds 4.5 metres to the fuselage, increasing thereby usable space by two additional pallets. Hence, it was capable of transporting eight 463L pallets or 97 medical litters per trip. Conversely, it can ferry 128 combat-ready troops or 92 Special Forces per mission.

Equipped with air-to-air refuelling capability for extended range operations and AN/AAR-47 Missile Approach Warning Systems, the C-130J, for its part can – unlike An-32s – conduct precision low-level flying, airdrops and extractions and landings in blackout conditions, as it ably demonstrated in Sudan last month.

A photo released by the IAF shows the small airstrip at Wadi Sayyidna in Sudan, in the dead of the night.

Other than its advanced digital avionics architecture and propulsion system, the C-130J’s configuration includes twin heads-up pilot displays which are certified as primary flight instruments, and dual mission computers that automate many functions, thereby allowing the platform to be operated by two pilots and a loadmaster.

“The C-17s and C-130J-30s operate primarily on the principle of easy handling, lean manning and economical running,” a flight engineer trained at Boeing’s C-17 final assembly facility at Long Beach in California, had declared when the aircraft were under induction in September 2013. They are a marvel in aviation engineering and their extraordinary STOL capability render them even more operationally compliant with India’s diverse terrain and varied requirement in an increasingly turbulent neighbourhood he declared, once again declining to be named.

The C-17s and C-130J-30s were undeniably a major step up from the IAF’s other transport assets, he added, an assessment vindicated by the evacuations in Sudan.