The Sukhoi Disaster

Issue: 06-2012By Air Marshal (Retd) V.K. Bhatia

While it may be premature to comment on the cause of the mishap; prima facie, this appears to be another tragic case of controlled flight into terrain

The Sukhoi Superjet 100 aircraft that crashed in Indonesia on May 9 was on its fourth stop of a ‘Welcome Asia’ promotional tour. The SSJ-100, tail number 97004 departed from Indonesian capital Jakarta’s Halim Perdanakusuma Airport at 1400 hours local time for a local demonstration flight and was due to return to the departure point.

This was the second demonstration flight the aircraft was operating that day. There were six crew, two representatives from Sukhoi and 37 passengers (mostly representatives of the region’s different air carriers) on board. At 1421 hours, the crew requested permission to descend from 10,000 ft to 6,000 ft while carrying out a right orbit. As there was no ostensible reason (or was there!?) to decline such a clearance, the flight was cleared for the descending right turn. This was the last transmission from the aircraft. It is worth noting that the aircraft had been cleared to operate in the airspace above the mountainous Bogor area. The choice of flying in the area of Bogor is often carried out considering the lack of flights in the airspace. There are no scheduled flights that pass through the region. But was the pilot in command aware of the mountainous terrain below and the fact that he was flying in the vicinity of 7,254-foot-high volcano, Mount Salak, a mountain higher than the requested flight level?

Preliminary reports indicate that the aircraft hit the edge of a cliff at an elevation of 6,270 ft, slid down a steep slope and came to rest at an elevation of 5,250 ft. Weather at the time of the accident was reportedly cloudy. Due to widespread debris field where the aircraft hit the mountain, it is assumed that the aircraft directly impacted the cliff side of the mountain at high speed with hardly a chance of survival. Once the crash site was found, there were no survivors.

The rescue operations and retrieval of the ‘Black Boxes’ were badly hampered by inclement weather and the treacherous terrain surrounding Mount Salak. But by May 16, all recoverable bodies had been removed from the crash site and taken to Jakarta for identification. In a heroic attempt, five members of the Indonesian Army’s Special Force Command (Kopassus), led by First Lieutenant Taufik Akbar managed to retrieve one of the ‘Black Boxes’, the cockpit voice recorder (CVR) which was handed over to the Indonesian National Committee of Transportation Safety (KNKT), will aid a great deal in determining the cause of the accident but, the more important flight data recorder (FDR) is yet to be found.

It has been rumoured that the ‘Welcome Asia’ tour was plagued pretty much from the get-go. After a successful demo flight in Kazakhstan, the tour moved to Pakistan, where potential buyers were forced to look at the jet only on the tarmac. One media report said it didn’t take to the sky because of a technical glitch, but that could not be confirmed. Later, on the way to Myanmar, a leak in one of the engine nozzles was discovered which warranted return of the aircraft to Moscow for repairs. SSJ-100 97004 — the one that crashed into the volcano — was a replacement aircraft that was sent to the region to continue the tour. However, even if the reports of technical glitches are taken at face value, they themselves confirm that flight safety was never sacrificed by the ‘Demo’ team and the first aircraft was promptly replaced by another fully serviceable second aircraft to complete the assignment.