Key Takeaways
- Air India Flight 171 experienced multiple technical failures in the 48 hours before its fatal crash
- The Boeing 787 had undergone stabiliser system repairs after a hard landing
- Critical fire prevention system was offline for two days before the accident
- Fuel cutoff switches automatically triggered seconds after takeoff, causing both engines to fail
New investigation findings reveal that Air India Flight 171 suffered multiple critical system failures in the two days leading up to the deadly crash that killed over 160 people earlier this year. The Boeing 787 Dreamliner experienced three serious electrical faults that compromised essential safety systems.
Previous Hard Landing Triggered Repairs
According to maintenance records obtained by The Federal, the aircraft had experienced a hard landing during its previous flight, prompting emergency repairs. Engineers replaced both the stabiliser position transducer and the horizontal stabiliser electric motor control unit just hours before the fatal flight from Ahmedabad airport.
Critical Systems Compromised
The investigation uncovered that the stabiliser motor shares power and data paths with other vital systems, including the fire inerter system designed to prevent fuel tank fires. This nitrogen generation system had been taken offline two days before the crash and remained inoperative when the flight departed.
Engineers had classified the fire inerter fault as “high-risk” requiring repair within 24 hours, but it was never fixed. A separate medium-risk core network issue was also flagged on June 9, affecting the digital-electrical system that manages most onboard functions.
Fuel Cutoff Triggered Catastrophe
The Aircraft Accident Investigation Bureau’s preliminary report confirmed that both engine fuel control switches automatically moved from ‘RUN’ to ‘CUTOFF’ position within seconds of takeoff. The switches turned off with just one second gap between them, causing complete engine failure.
Cockpit voice recorder transcripts reveal one pilot questioning the other about why he switched off the fuel supply, with the second pilot denying any action. The switches were later reactivated, but one engine could not recover from the deceleration.
The interconnected nature of Boeing 787 systems meant that faults in one area could cascade through multiple critical functions, ultimately affecting engine control and fuel management systems.
