The Aircraft Accident Investigation Bureau (AAIB) has published an initial report on its investigation into the Air India crash in Ahmedabad that claimed the lives of 241 passengers, leaving just one survivor.
On June 12, Air India’s AI171 flight took off from Ahmedabad airport en route to London’s Gatwick. However, just moments after takeoff, the Boeing 787-8 Dreamliner crashed near the airport. The aircraft struck the hostel premises of BJ Medical College, killing 19 people on the ground. With 241 passengers onboard also losing their lives, the total death toll rose to 260—making it one of the deadliest aviation disasters in India’s recent history.
Most air crashes are caused by a mix of factors, not just one. Under international rules, a preliminary report must be released within 30 days, with the final report usually expected within a year.
In this case, the aircraft’s black boxes—containing the cockpit voice recorder and flight data recorder—were recovered and downloaded in India.
Here are the key takeaways from the report-
"Why Did You Cut Off?": Cockpit Conversation Reveals In-Flight Confusion
Soon after the aircraft reached 180 knots (a typical takeoff speed), both engines' fuel switches were unexpectedly flipped to the ‘Cutoff’ position, cutting off fuel supply mid-air. Just seconds later, the switches were turned back to ‘Run’, indicating an urgent attempt to restart the engines. The cockpit voice recorder captured a tense exchange: one pilot asked, “Why did you cut off?” and the other responded, “I did not do so.” This moment points to a possible miscommunication or even a malfunction in the engine control system.
Both Engines Lost Power Moments After Takeoff
Immediately after takeoff, both engines began to fail. A jet engine must maintain a minimum rotational speed—known as “idle speed”—to keep the airflow and fuel combustion stable. In this case, the core speeds of both engines fell below that threshold, meaning they could no longer generate enough thrust. This sudden loss of power, combined with the low altitude during climb-out, left the aircraft with little chance of recovery.
Engine Restart Attempts Had Mixed Results
After fuel was restored, the pilots tried to relight the engines. Engine 1 responded better as it stopped slowing down and began showing signs of recovery. But Engine 2 continued to deteriorate. Even though it did reignite, it couldn’t maintain the necessary speed and kept failing, despite repeated efforts to introduce fuel. This meant that the plane still didn’t have enough power to stay airborne.
Flight Recorder Confirmed Relight Efforts
Data from the flight recorders showed that Exhaust Gas Temperature (EGT)—a key indicator of whether combustion is happening in the engines—rose during the relight attempts. This confirmed that fuel was burning again briefly in both engines. However, it wasn't enough to fully restart or stabilise them. One of the recorders was too damaged to retrieve full data, which may have held additional clues about what went wrong.
Investigation Still Ongoing, No Safety Alerts Issued Yet
The Aircraft Accident Investigation Bureau (AAIB) continues to examine what led to the fatal crash, and the probe remains in its early stages. Investigators are still gathering additional data from stakeholders, including Air India, Boeing (the aircraft manufacturer), and General Electric (maker of the GEnx-1B engines).
So far, no interim safety recommendations have been issued to either Boeing or GE. The AAIB has also confirmed that the rear Engine and Aircraft Flight Recorder (EAFR) was severely damaged and could not be downloaded using conventional methods—limiting the available data. Despite this, the front recorder and cockpit voice data have helped reconstruct parts of the timeline, especially regarding engine behaviour and crew response.
