A month after the devastating crash of an Air India Dreamliner that killed at least 270 people, a preliminary report by the Aircraft Accident Investigation Bureau (AAIB) has shed light on the final moments of Flight AI171. The report, released early Saturday, revealed a critical detail that both engine fuel switches on the Boeing 787-8 aircraft were moved from ‘RUN’ to ‘CUTOFF’ seconds after takeoff.
According to the 15-page report, cockpit voice recordings captured a tense exchange between the two pilots. “Why did you cut off?” one pilot asked. The other replied, “I didn’t do so.” The simultaneous transition of both engines’ fuel switches suggests a sudden shutdown of fuel supply, which investigators believe could be a key piece in understanding the crash on June 12.
Switches moved from ‘RUN’ to ‘CUTOFF’
The aircraft had taken off at 08:08:39 UTC (13:38:39 IST) from Ahmedabad for a scheduled flight to London. At 08:08:42 UTC, the plane reached its maximum recorded airspeed of 180 knots. Immediately after, Engine 1 and Engine 2 fuel cutoff switches moved from ‘RUN’ to ‘CUTOFF’, within one second of each other.
As the report notes, this led to a decrease in both engines’ N1 and N2 values due to the sudden loss of fuel supply. In a desperate attempt to regain control, the pilots transitioned the switches back to ‘RUN,’ initiating a relight and thrust recovery sequence as managed by the aircraft’s Full Authority Dual Engine Control (FADEC) system. However, the Enhanced Airborne Flight Recorder (EAFR) stopped recording just seconds later.
"In the cockpit voice recording, one of the pilots is heard asking the other why did he cutoff. The other pilot responded that he did not do so," the report said
Flight crash claimed 260 lives
At 08:09:05 UTC (13:39:05 IST), one of the pilots issued a ‘MAYDAY’ alert. The Air Traffic Controller (ATCO) immediately responded, asking for the call sign, but received no reply. The aircraft crashed moments later outside the airport boundary.
The incident marks the first fatal accident involving a Boeing 787 and resulted in the deaths of 260 people both onboard and on ground, with only one survivor from the flight. The aircraft had crashed into a medical college hostel building and resulted in the deaths of many students as well as medical staff.
DGCA tested samples from bowsers and tanks
"The ATCO (Air Traffic Controller) enquired about the call sign. ATCO did not get any response but observed the aircraft crashing outside the airport boundary and activated the emergency response," the report said.
Despite the tragic event, the AAIB has not recommended any immediate action for other operators of Boeing 787-8 aircraft. At the time of the crash, the co-pilot was flying the plane while the captain was in the monitoring role.
The report also confirmed that fuel samples taken from bowsers and tanks used to refuel the aircraft were tested by the Directorate General of Civil Aviation (DGCA) and were found to be satisfactory. Investigations are ongoing to determine the exact cause of this catastrophic crash.
