Did pilot error or a glitch in upgrade lead to the Mirage 2000 crash that killed two Indian Air Force (IAF) test pilots at the HAL Airport here on February 1? Reports citing Defence Ministry sources on the Court of Inquiry (CoI) now indicate that the aircraft’s upgrade could be the cause.
The crash was reportedly attributed by the CoI to a software glitch, an ‘uninitiated control input’. This fatal turn occurred just when the aircraft, upgraded by the Hindustan Aeronautics Limited (HAL), was on a user acceptance trial.
Both pilots Squadron Leaders Samir Abrol and Siddhartha Negi had ejected out but the parachutes caught fire, causing them fatal burns. They were attached to the Aircraft and Systems Testing Establishment (ASTE) attached to the IAF.
Refuting the reports, HAL sources maintained that the CoI is yet to be finalised and it is too premature to comment. However, the state-owned aviation major clarified that it is not involved in the aircraft’s software development and thus had no role in any glitch.
Days after the crash, a few aviation experts had wondered why the arrester barrier at the HAL Airport runway did not halt the aircraft that had slid at high speeds after its landing gear came away. The CoI reportedly found fault with the barrier, essentially a net fitted with hydraulic jacks at the runway end.
Before the upgraded aircraft was delivered for acceptance trials, HAL’s own test pilots had completed six sorties. The crash occurred when the aircraft was on its second acceptance sortie by the ASTE pilots. HAL sources had maintained that no glitch was noted during the first six sorties.
The aircraft’s flight data recorder (black box), recovered from the crash site by a team of officials from the IAF and HAL, was later taken to Dassault Aviation, the Mirage 2000’s Original Equipment Manufacturer (OEM) based in France.
Black box returns
It is learnt that the black box has been sent back to India after a thorough analysis of the recovered data. The sources said there were a lot of ‘interpretative issues’ with the assessment and further analysis has to be carried out.
The final CoI report is expected to shed more light on what actually led the aircraft to lift off the ground briefly before sliding down the runway with its nose down. The main landing gear (MLG) had collapsed on impact.