The crash of Air India flight AI171, a Boeing 787-8 Dreamliner en route from Ahmedabad to London Gatwick, has claimed 241 lives of passengers and crew, along with 19 people on the ground. The Aircraft Accident Investigation Bureau (AAIB) has released its preliminary report, focusing on the unprecedented movement of engine fuel control switches.
Preliminary Report Findings
The AAIB's preliminary report indicates a critical technical anomaly: the engine fuel control switches abruptly shifted from the 'RUN' to 'CUTOFF' position within one second of each other shortly after takeoff. This action resulted in an immediate loss of power to both engines. The report also included a cockpit voice recording where one pilot is heard questioning the other about cutting off the fuel supply, but the other pilot denied doing so. Intriguingly, the switches were found in the 'RUN' position in the wreckage, deepening the mystery.
Expert Opinions and Analysis
Commercial pilot Rajiv Pratap Rudy noted that the aircraft's takeoff appeared normal and the fuel switch was correctly positioned. Despite the pilot's efforts to relight the engines, the cause of the flameout remains unclear. Aviation experts are urging caution against drawing premature conclusions, emphasizing the need for a comprehensive investigation into all potential factors, including mechanical failure.
Group Captain Aurobindo Handa (retired), former Director General of the AAIB, suggested that making the change of fuel cutoff switches mandatory, after the FAA advisory in 2018, would have been a better application of mind.
The Significance of Fuel Switch Position
The fuel control switches have brackets on either side to protect them. There is also a stop lock mechanism that requires the pilots to lift the switch before moving it from either of its two positions – RUN and CUTOFF – to the other. These switches are usually only moved when the aircraft is on the ground to start the engines before departure and to shut them down after landing. An aviation expert has said that the fuel switches are designed so that this cannot easily "accidentally" happen.
FAA Advisory and Air India's Response
Investigators noted a previous US Federal Aviation Administration (FAA) advisory from December 2018 regarding a potential flaw in the aircraft's fuel-control switch system, highlighting the potential disengagement of the locking feature. Air India told the investigators that no inspection had been made in response to this SAIB, since compliance was not mandatory.
Possible Causes and Ongoing Investigation
The AAIB has not ruled out the possibility of crew error, aircraft system malfunction, or a design-related fault. The investigation is still reviewing cockpit actions, system inputs, and procedural adherence in the minutes before the crash. The flight data is still under analysis, and additional information from Boeing and GE is being sought.
Air India's Response
Air India has stated that it is cooperating fully with authorities in the investigation and is providing support to the affected families. They acknowledged receipt of the preliminary report released by the AAIB.
The crash of AI171 is among the deadliest aviation disasters involving an Indian airline in four decades. The investigation is ongoing, with a focus on determining the precise reasons behind the engine failure and the sequence of events that followed.
