The crash of Air India Flight 171 on June 12, 2025, has prompted a thorough investigation, with the recently released black box data offering a crucial glimpse into the final moments of the flight. The Boeing 787-8 Dreamliner, en route to London Gatwick from Ahmedabad, crashed shortly after takeoff, killing 241 of the 242 people on board, as well as 19 people on the ground. The aircraft, carrying 230 passengers and 12 crew members, impacted a hostel block of B. J. Medical College, resulting in multiple explosions and a devastating scene.
The preliminary report by India's Aircraft Accident Investigation Bureau (AAIB) indicates that both engines lost thrust seconds after takeoff, as the fuel control switches moved from the "RUN" to "CUTOFF" position. The cause of this switch movement is currently under intense investigation. The flight data recorder revealed that the throttles remained at takeoff thrust until the moment of impact, but the thrust levers were recovered in the idle position. The aircraft took off from runway 23 at Ahmedabad Airport at 13:38 IST (08:08 UTC). Approximately 30 seconds later, at 08:09:05 UTC, a pilot issued a "mayday" call. The air traffic controller responded, but received no reply before the aircraft crashed.
Analysis of the cockpit voice recording (CVR) reveals a perplexing exchange between the pilots. One pilot is heard asking the other why he cut off the fuel, to which the other responded that he did not. This suggests that one pilot noticed the fuel cutoff, while the other denied initiating it. Within 10-14 seconds of the fuel cutoff, the pilots moved both fuel switches back to the "RUN" position, initiating automatic restart sequences for both engines. However, the aircraft crashed shortly afterward.
The investigation is considering several possibilities, including human error, system failure, or design issues. The fuel control module, which houses the fuel control switches, is equipped with brackets to prevent accidental movement. Investigators are trying to determine whether the fuel control switches were moved improperly, inadvertently, or intentionally. The AAIB stresses that the information is preliminary and subject to change. The investigation team is reviewing and examining additional evidence, records, and information. Detailed analysis of the black box data is ongoing. Additional cockpit voice recorder analysis may reveal more details about crew communications and any alarms that may have gone off.
The crash of Air India Flight 171 is the first fatal accident and hull loss involving a Boeing 787 Dreamliner. The recovery of the black boxes was a meticulous process, with both the Cockpit Voice Recorders (CVR) and Flight Data Recorders (FDR) being recovered from the crash site. The devices were kept under 24x7 police protection and CCTV surveillance before being transported to Delhi for data extraction and analysis. The data extraction process involved technical members from the AAIB and the National Transportation Safety Board (NTSB). The analysis of CVR and FDR data is underway to reconstruct the sequence of events leading to the accident and identify contributing factors to enhance aviation safety and prevent future occurrences.
