The preliminary report regarding the Air India Flight AI171 crash in Ahmedabad on June 12, 2025, has been released by the Aircraft Accident Investigation Bureau (AAIB). The report, which is 15 pages long, offers the first official insight into the possible cause of the tragic event. The crash of the Boeing 787 Dreamliner shortly after takeoff resulted in at least 270 fatalities.

The key finding of the preliminary report confirms that both engines shut down mid-air within seconds of take-off. Specifically, the fuel cutoff switches, which control the flow of fuel to the engines, transitioned from the "RUN" to "CUTOFF" position in quick succession. This occurred just three seconds after takeoff, with the switches moving within one second of each other, leading to a sudden loss of thrust. The pilots seemed confused about the cause, with one pilot asking, "Why did you cutoff?" and the other replying, "I did not do so," which suggests a potential technical malfunction or inadvertent activation.

The aircraft reached a maximum speed of 180 knots indicated airspeed (IAS) just before both Engine 1 and Engine 2 fuel cutoff switches transitioned from "run" to "cutoff". This effectively shut down both engines in-flight. After an initial loss of thrust, the engines experienced a momentary recovery, but ultimately failed to stabilize.

Notably, the Ram Air Turbine (RAT), an emergency power source, deployed immediately after liftoff, indicating a total loss of power to essential systems. A mayday call was issued seconds before the crash. The aircraft crashed into a student hostel near the airport, impacting buildings with an 8° nose-up attitude and level wings, but with both engines inactive.

Investigators are focusing on the possibility of fuel control switch movement as a potential cause for the dual engine failure shortly after takeoff. Experts say that moving the fuel control switches to the cutoff position would stop fuel flow, shutting down the engines in seconds.

While the report is factual and restrained, it offers critical early clues. Authorities are not expected to assign blame yet, as a full investigation is ongoing. Both the cockpit voice and flight data recorders have been recovered and their contents extracted.

According to a New York Times report, investigators and aviation experts have concluded that both engines failed simultaneously, possibly due to fuel contamination or incorrect input of flight parameters before takeoff. However, an aviation attorney suggests that a Thrust Control Malfunction Accommodation (TCMA) failure may have caused the crash. The TCMA tells the Full Authority Digital Engine Control (FADEC), which controls airspeed and thrust on the engines, whether it is on the ground or in the air.

The investigation continues to determine the exact cause of the engine shutdowns and the subsequent crash.