Human error, faulty design behind Saras crash: Report

Barely a month before the fatal crash, the ill-fated Saras aircraft flew in Aero India 2009 for four days without the Director-General of Civil Aviation’s (DGCA) permission.
“Aircraft was used for flying demonstration in Aero India 2009 from February 11-15, 2009 at Bangalore. But no DGCA permission was taken by the National Aerospace Laboratories (NAL),” says the DGCA probe report on the fatal crash on March 6, 2009 that killed three Indian Air Force (IAF) personnel.

The report says there is no effective and continuous monitoring of the Saras test programme by the management committee (MC) comprising representatives from NAL and IAF’s Aircraft and System Testing Establishment (ASTE).

This happened despite a 2003 agreement between NAL and IAF agreeing that the MC will deliberate and decide on all major issues relating to flight test planning, sequencing and supervision of flight tests and safety aspects.

But after August 2006, there was no periodical review by the MC. There was only one joint meeting between the NAL and ASTE on August 28, 2008. After this meeting there were 27 test flights. None was reviewed.

NAL also did not coordinate well with engine manufacturer Pratt and Whitney and German propeller manufacturer, MT. As a result, it devised an incorrect relight procedure, which was vetted by the ASTE. Relighting – switching off the engine mid-air and re-ignite after few seconds – is a standard procedure for any aircraft to get the airworthiness certificate.

The CSIR laboratory flouted other DGCA norms as well. It sub-contracted a Bangalore-based private firm, Aircraft Design and Engineering Service, which not only almost did the entire design and development of Saras project but also conducted the flight testing analysis. The digital flight data recorder in the cockpit does not have critical engine parameters like engine oil pressure, inner turbine temperature and fuel flow to monitor these in relight procedures.

The fatal accident may not have taken place had the pilots took the flying conditions more seriously after the first re-ignition attempt failed. They went for a second relight attempt without having adequate height.