The Aircraft Accident Investigation Bureau (AAIB) has released its preliminary findings into the catastrophic crash of Air India Flight AI171, a Boeing 787-8 Dreamliner, which occurred on 12 June 2025 shortly after takeoff from Ahmedabad. The tragedy claimed 260 lives and marked the first fatal h...
The Aircraft Accident Investigation Bureau (AAIB) has released its preliminary findings into the catastrophic crash of Air India Flight AI171, a Boeing 787-8 Dreamliner, which occurred on 12 June 2025 shortly after takeoff from Ahmedabad. The tragedy claimed 260 lives and marked the first fatal hull loss of a Dreamliner globally.
Key Developments from the AAIB Report:
1. Flight Timeline and Engine Behavior
- The aircraft reached a maximum speed of 180 knots IAS seconds after liftoff.
- Immediately following this, both Engine 1 and Engine 2 fuel cutoff switches transitioned from RUN to CUTOFF within one second of each other.
- Engine N2 values dropped below minimum idle speed, indicating a complete loss of thrust.
- EGT (Exhaust Gas Temperature) readings began rising, suggesting attempted engine relight.
- Both fuel cutoff switches were later toggled back to RUN, but the aircraft was already at critically low altitude.
2. Cockpit Voice Recorder Revelations
- One pilot is heard asking the other, “Why did you cutoff?” to which the response was, “I didn’t.”
- This exchange has raised questions about possible inadvertent switch activation or system malfunction.
3. Flight Data Recorder Status
- The forward Enhanced Airborne Flight Recorder (EAFR) was successfully accessed.
- The aft EAFR was substantially damaged and could not be downloaded through conventional means.
4. Fuel Quality and Contamination Checks
- Fuel samples from bowsers and tanks used for refueling were tested at DGCA’s lab and found satisfactory.
- Limited fuel samples retrieved from the aircraft itself are undergoing further testing.
5. Maintenance and Airworthiness
- All Airworthiness Directives and Service Bulletins had been complied with.
- The aircraft had active MELs (Minimum Equipment List items), none of which were linked to engine control systems.
- A prior FAA advisory from 2018 warned of potential disengagement of fuel switch locking mechanisms, but Air India did not act on it as it was non-mandatory.
6. Human Factors and Medical Analysis
- Postmortem reports of crew and passengers are being analyzed to correlate aeromedical findings with engineering data.
- Both pilots had sufficient rest and experience on the aircraft type.
7. Wreckage and Investigation Status
- Engines and key components have been quarantined for further examination.
- Drone-based imaging and debris mapping have been completed.
- Statements from eyewitnesses and the lone survivor have been recorded.
8. Air India’s Response
- Air India has acknowledged receipt of the AAIB’s preliminary report.
- The airline reiterated its full cooperation with investigative authorities.
Next Steps:
The AAIB has not issued any immediate safety recommendations for Boeing or GE. The investigation continues, with deeper analysis expected in the final report due within a year.
Sources: CNBC-TV18, The Hindu, Indian Express, Moneycontrol, Deccan Herald, Firstpost, AAIB Preliminary Report Document