The Air India flight AI171 suffered a fatal crash while on its way to London from Ahmedabad on June 12 claiming all except one life aboard just second after its take off. The Aircraft Accident Investigation Bureau (AAIB) has published a 15-page preliminary investigation report detailing the fateful 98 seconds of its journey from take off to its crash into a medical college hostel in Ahmedabad.
The Boeing 787-8 Dreamliner took off at 1:38 pm after receiving take-off clearance and was just 32 seconds in the air before it crashed. The time of accident as noted by AAIB was 1:39 pm. The aircraft was destroyed due to impact with the buildings on the ground and subsequent fire.
Sequence of impact: How the tragedy unfolded
As the aircraft rapidly lost altitude, it first struck a series of trees and an incineration chimney located within the Army Medical Corps compound. It then impacted the northeast wall of Building A. The distance between the first tree the aircraft hit and the point of impact on Building A was approximately 293 feet. As the plane continued forward, it began to disintegrate, colliding with other structures and nearby vegetation.
Impact marks found on both the building and aircraft suggest that the plane hit in a nose-up position, estimated at around 8 degrees, with wings level. These findings indicate that the aircraft maintained a somewhat controlled attitude even in its final moments before the crash.
The vertical stabiliser was torn off from the rear of the fuselage and landed about 200 feet south of Building A’s initial impact point. Meanwhile, the tail section and the right-hand main landing gear became embedded in the building’s northeast wall, as the rest of the aircraft continued moving forward, breaking apart further upon impact.
Final moment of Flight AI171: A second-by-second timeline of the crash
13:37:33 IST – Air Traffic Control issued take-off clearance.
13:37:37 IST – Aircraft began rolling on the runway.
13:38:33 IST – Aircraft crossed take-off decision speed (V1) and reached 153 knots IAS.
13:38:35 IST – Aircraft achieved Vr speed (155 knots).
13:38:39 IST – Aircraft's air/ground sensors transitioned to air mode, indicating liftoff.
13:38:42 IST – Aircraft reached maximum recorded airspeed of 180 knots IAS.
Immediately after, Engine 1 and Engine 2 fuel cutoff switches transitioned from RUN to CUTOFF, one second apart. Engines (N1 and N2) started decreasing as fuel supply was cut off.
13:38:43–45 IST (approx) – In cockpit audio, one pilot asked, "Why did you cut off?" The other replied, "I didn’t."
13:38:45 IST – CCTV footage showed the Ram Air Turbine (RAT) deploying during initial climb. Aircraft began losing altitude before crossing the airport perimeter wall.
13:38:47 IST – RAT hydraulic pump began supplying power as engine N2 values fell below idle speed.
13:38:52 IST – Engine 1 fuel cutoff switch was moved back from CUTOFF to RUN.
13:38:54 IST – APU Inlet Door began opening — consistent with APU Auto Start logic.
13:38:56 IST – Engine 2 fuel cutoff switch also moved from CUTOFF to RUN.
13:39:05 IST – One of the pilots transmitted: "MAYDAY MAYDAY MAYDAY". ATC received no further response. Aircraft crashed outside the airport boundary.
No bird activity was detected near the flight path. In the cockpit recording, one pilot asked the other why the fuel was cut off, to which the other replied he hadn't done it.
Here are some stories related to the Air India plane crash: