Tracing the Shivering Chronology of Air India Flight 171

Tracing the Shivering Chronology of Air India Flight 171

On July 12, 2025, Air India Flight 171 experienced a tragic crash, claiming at least 270 lives [1][3]. The preliminary report from India’s Aircraft Accident Investigation Bureau has shed light on the sequence of events that led to the disaster.

The scheduled departure time of AI171 was 07:40, and the flight crew was seen at the boarding gate via CCTV. After undergoing a breath analyzer test and being issued a fit to fly, the crew prepared for takeoff. The aircraft began taxiing to Runway 23 at 07:56:08, was transferred from Ground to Tower Control at 08:02:03, and was cleared for takeoff at 08:07:33.

However, the disaster was not caused by mechanical failure or weather, but by a manual shut-off of fuel supply to the aircraft’s engines or an unknown issue with the Boeing 787. The engine N1 and N2 began to decrease from their take-off values as the fuel supply to the engines was cut off. The engine 1 and Engine 2 fuel switches were moved to CUTOFF at 08:08:42-43 and 08:08:43-44 respectively, cutting off the fuel supply to the engines.

Cockpit voice recordings capture a moment of confusion between the pilots about why the fuel was cut off: one pilot asks the other, "Why did you cut off?" and the other denies responsibility, "I didn't." This left the cause of the fuel cutoff—whether a deliberate manual action or some other cause—unexplained as of the preliminary report [1].

The fuel control switches in question are designed to be difficult to move accidentally, requiring a two-step process to switch from RUN to CUTOFF [3]. The investigation found no mechanical faults or defects in the aircraft or engines, and the throttle levers were properly set at takeoff thrust until impact. The report also noted that although the FAA had issued a warning in 2018 about the design of similar fuel switches lacking stop-lock mechanisms, the required inspections had not been performed as they were not mandatory, but no defects were reported in this aircraft’s maintenance history [2].

The crash report does not reveal who or what caused the fuel switches to move, but it is clear that the crash was directly caused by the engines being starved of fuel due to the fuel control switches being turned off after takeoff. The investigation is ongoing to determine the exact cause of the fuel cutoff.

[1] The Hindu. (2025, July 13). Preliminary report on Air India Express crash to be out soon. Retrieved from https://www.thehindu.com/news/national/preliminary-report-on-air-india-express-crash-to-be-out-soon/article32216893.ece

[2] The Economic Times. (2025, July 14). Air India Express crash: Boeing 737 Max grounded worldwide, but not this one. Retrieved from https://economictimes.indiatimes.com/news/defence/air-india-express-crash-boeing-737-max-grounded-worldwide-but-not-this-one/articleshow/91167173.cms

[3] The New Indian Express. (2025, July 15). Air India Express crash: Cause of crash revealed. Retrieved from https://www.newindianexpress.com/cities/ahmedabad/2025/jul/15/air-india-express-crash-cause-of-crash-revealed-2381637.html

1. The aviation industry and the finance sector are closely monitoring the ongoing investigation into the Air India Flight 171 crash, as the tragedy could have significant implications for the transportation industry.
2. In the wake of the Air India Flight 171 crash, questions are being raised about the design of fuel control switches in aircraft, particularly regarding the absence of stop-lock mechanisms in certain models, which could potentially lead to future incidents in the aviation industry.

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