Introduction
India’s Aircraft Accident Investigation Bureau (AAIB) has revealed that a 2018 FAA advisory flagged a possible issue with the fuel-control switch on Boeing 787 jets. This insight emerges during the preliminary investigation of the June 12, 2025 Air India Flight AI‑171 crash.
Timeline of Events
June 12, 2025: Flight AI‑171 departs Ahmedabad bound for London Gatwick. Just 32 seconds after lift-off, cockpit recordings capture the sudden movement of both engine fuel switches from “RUN” to “CUTOFF,” causing dual engine flame-out 1.
The fuel switches were returned to “RUN” shortly afterward in an attempt to restart engines. Despite one engine relighting, the aircraft crashed due to insufficient altitude for recovery 2.
Role of 2018 FAA Advisory
In December 2018, the U.S. Federal Aviation Administration (FAA) issued Special Airworthiness Information Bulletin (SAIB NM‑18‑33), highlighting that some Boeing 737-style fuel-control switches had disengaged locking mechanisms — making them prone to inadvertent activation 3.
Although advisory and non-binding, questions arose whether Air India inspected their Boeing 787 fleet, as the system design mirrored the 737’s locking mechanism. Air India confirmed no inspections were carried out since the bulletin was advisory 4.
Cockpit Confusion and Pilot Exchange
Cockpit Voice Recorder transcripts captured one pilot saying, “Why did you cut off the fuel?” with the other responding, “I did not do so.” Neither pilot claimed responsibility. Mechanical failure of the switches is deemed unlikely due to their spring-loaded design and locking features 5.
Aircraft and Crew Details
The Boeing 787‑8 (VT‑ANB) carried around 12 years of service, had over 41,000 flight hours, and underwent throttle-control module replacements in 2019 and 2023—neither linked to fuel-switch defects 6.
Pilot Captain Sumeet Sabharwal (15,000+ hours; 8,600 on 787) and First Officer Clive Kunder (3,400 hours) were rested, certified, and breathalyser-cleared before departure 7.
Key Technical Findings
- Both fuel switches flipped to “CUTOFF” within a second post‑lift‑off, prompting Ram Air Turbine (RAT) deployment for emergency power 8.
- Pilots restored switches to “RUN” ~10 seconds later; engine relaunch started but altitude was insufficient 9.
- Fuel contamination, bird strike, or bad weather were ruled out. The Emergency Locator Transmitter also failed to activate despite high-impact conditions 10.
What Remains Unresolved
— Cockpit camera recordings are unavailable, making it harder to trace actual switch movement 11.
— Whether the cut‑off was intentional, accidental, or due to an electrical fault (e.g., engine ECU microprocessor glitch) remains under investigation 12.
— The non‑mandatory status of the FAA advisory has raised questions on the oversight of such “advisory-only” safety bulletins 13.
Next Steps & Wider Implications
The AAIB’s final report is expected within a year, after detailed analysis of flight data, cockpit audio, systems, and hardware 14.
The incident highlights the need for reevaluating how “advisory” safety bulletins are treated and whether select findings should be made mandatory to prevent future tragedies.
Source: The Times Of India