New Delhi: The Air Accidents Investigation Branch (AAIB) has published its preliminary report into the devastating Air India AI171 crash, which resulted in the loss of nearly all lives on board. The flight, departing from Ahmedabad, India, and destined for London, experienced a catastrophic dual-engine failure mere seconds after takeoff. The aircraft plunged to the ground within approximately 32 seconds.
The report centres on the sudden and inexplicable fuel cutoff that initiated the engine failure. Cockpit voice recordings reveal confusion and uncertainty amongst the pilots in the brief moments before the crash. One pilot is heard questioning the other regarding the fuel cutoff, only to be denied responsibility, a point which heavily suggests a mechanical fault.
The AAIB’s findings indicate that the aircraft was fully functional up until three seconds post-takeoff. At this point, both engines lost power, with the aircraft succumbing to the loss of thrust within 10–14 seconds. The report emphasises the highly unusual and critical nature of a simultaneous fuel cutoff to both engines.
The investigation focuses on several key areas. First, the report scrutinises the design of the fuel cutoff switches. The switches, located on the frontal deck, are designed to require a deliberate and conscious action to engage, making accidental activation highly improbable. This raises questions about the possibility of a malfunctioning mechanism within the switch itself.
Secondly, the AAIB will explore whether any previous safety advisories, such as the Federal Aviation Administration’s (FAA) SAIB 18 of 33, issued in December 2018, concerning potential fuel control switch locking mechanism issues on Boeing 737 and similarly designed Boeing 787 aircraft, were adequately addressed by the airline. The preliminary report does not determine whether adherence to these advisories played a role in the accident.
Finally, the AAIB will thoroughly analyse the flight data recorder and cockpit voice recorder information, along with other relevant data, to reconstruct the events leading up to and including the crash. This will entail a detailed examination of all systems and operational parameters to determine the root cause of the fuel cutoff and subsequent engine failure. The final, comprehensive AAIB report is awaited.