Air India Flight AI171 Crash – Preliminary Report Summary
Basic Flight and Crash Information
- Flight: AI171 from Ahmedabad (VAAH) to London Gatwick (EGKK)
- Date/Time: 12 June 2025, 0809 UTC (13:39 IST)
- Aircraft: Boeing 787-8, registration VT-ANB, operated by Air India
- Phase of Flight: Initial Climb
- Fatalities: All 241 on board (2 flight crew, 10 cabin crew, 229 passengers) and 19 on the ground
- Wreckage Site: Impacted buildings approx. 0.9 NM from the end of Runway 23, including BJ Medical College hostel
Flight Crew Information
- Captain: 56-year-old male, ATPL holder, 15,638 hours total time (8,596 on type), fully qualified PIC
- First Officer: 32-year-old male, CPL holder, 3,403 hours total (1,128 on type), PF for this flight
Aircraft and Maintenance Status
- Aircraft manufactured in 2013, fully airworthy with all Airworthiness Directives and Service Bulletins complied
- Active MELs included minor cockpit/cabin systems and one CAT A MEL for nitrogen generation—none deemed contributory
- Fuel control switch inspections (per FAA SAIB NM-18-33) were not performed, as the directive was advisory only
Accident Sequence Based on EAFR and CVR Data
Normal Takeoff Sequence
- Pushback at 07:43 UTC; takeoff clearance issued at 08:07:33 UTC
- Aircraft began takeoff roll at 08:07:37 UTC; rotation speed (Vr) of 155 knots reached at 08:08:35 UTC
- Aircraft lifted off and transitioned to air mode at 08:08:39 UTC
- Reached max speed of 180 knots at 08:08:42 UTC
Sudden Engine Shutdown
- At 08:08:42 UTC, both fuel cutoff switches transitioned from RUN to CUTOFF, one second apart
- Engine power (N1/N2) began declining due to fuel starvation
- CVR recorded a pilot asking, “Why did you cut off?” and the other responding, “I did not”
- RAT (Ram Air Turbine) deployed at 08:08:47 UTC to restore hydraulic power
Attempted Recovery
- At 08:08:52 UTC: Engine 1 fuel control switch returned to RUN
- At 08:08:56 UTC: Engine 2 switch also returned to RUN
- FADEC attempted auto-relight: Engine 1 began recovering; Engine 2 failed to stabilize
- EGT rise confirmed attempted relight on both engines
- Mayday call transmitted at 08:09:05 UTC; final data recorded at 08:09:11 UTC
- Aircraft crashed into residential structures beyond airport perimeter
Investigation Highlights
Wreckage Findings
- Thrust levers found in idle, but flight data shows they were at takeoff thrust until impact
- Fuel switches found in RUN, suggesting they were reset prior to crash
- Gear lever and flaps were in normal takeoff configuration (flaps 5, gear down)
Fuel Switch Design Concern
- The 787’s fuel switches (Part No. 4TL837-3D) share design with older 737 models
- Prior advisory (SAIB) warned of locking mechanism issues potentially allowing accidental shutoff
- Inspections recommended by FAA were not performed by Air India
- Investigation is exploring inadvertent switch actuation during takeoff due to turbulence or guarding hand contact, however intentional movement of the switches has not been ruled out
Next Steps and Interim Conclusion
- No safety recommendations yet issued for 787-8 aircraft or GE GEnx-1B engines
- Investigation ongoing; focus areas include:
- Engineering review of fuel control switches
- Detailed aeromedical analysis of crew
- Analysis of cockpit coordination, workload, and procedure execution
- Answer the question of “why did the fuel cutoff switches move to the off position?”
4 Comments
The failure of both the fuel cutoff switch locks within 1 second of each other is EXTREMELY improbable. That would give the CVR comments context, however. Accidental cutoff by a pilot seems even more unlikely. That means a pilot intentionally moved the switches to “Cutoff” and was noticed in the cutoff position by the other pilot, again giving context to the CVR recording. One other idea… was there a third person in the cockpit? The CVR does not seem to suggest that, however. There does not seem to be any “fight” over restoring the switches to the “Run” position, adding more doubt to intentional switch activation. This is completely baffling and I hope the investigation can eventually narrow the events to a cause.
The fact that the switches went to cutoff sequentially and not simultaneously is positive indication of human intervention. Someone consciously put those switches to cutoff. Who and why are now the big questions.
An experienced pilot would have realized that there wasn’t time to relight the engines, or even one, and resume sufficient thrust to arrest the descent. There would be no reason to fight over the switches. They were already dead, they just hadn’t stopped breathing.
Most critical switches in the aircraft I’ve flown have been guarded to prevent accidental activation. If on purpose you had to move the guard. Seems as if fuel cut off would fit this category. Investigated many accidents where activation of a guarded switch was the claimed cause
Really?. If not guarded, maybe they should be.