Air India plane crash: What can we conclude from bombshell AAIB report on Ahmedabad tragedy

Air India flight AI171’s preliminary crash report was released on Saturday, July 12. Was the deadly crash a result of a technical issue? Was it a software issue? Or was it a human error? Here’s what we can conclude from the Aircraft Accident Investigation Bureau (AAIB) report:

While the preliminary crash report details the situation in the cockpit seconds before the Ahmedabad plane crash, the exact cause of the plane crash remains unresolved.

However, investigators say there are two main takeaways from the preliminary report on Air India Flight 171.

1. Engine fuel cut off

The London-bound Air India experienced a “fuel cut off” seconds after taking off from Ahmedabad’s Sardar Vallabhbhai Patel International Airport (VAAH) on June 12.

The report revealed that both engine fuel cut off switches moved from run to cut off within seconds of takeoff, abruptly cutting the plane’s thrust at 180 knots.

It said, “The aircraft achieved the maximum recorded airspeed of 180 Knots IAS at about 08:08:42 UTC and immediately thereafter, the Engine 1 and Engine 2 fuel cutoff switches transitioned from RUN to CUTOFF position one after another with a time gap of 01 sec.”

“The Engine N1 and N2 began to decrease from their take-off values as the fuel supply to the engines was cut off,” the report added.

Flight data indicated that the pilots re-engaged the fuel switches in an attempt to relight both engines. Engine 1 showed signs of recovering thrust, but Engine 2 failed to stabilise.

The aircraft, which had briefly reached a speed of 180 knots, was already descending and failed to regain altitude. “The aircraft started to lose altitude before crossing the airport perimeter wall,” the report stated.

2. Fuel switch locking mechanism

Second, the preliminary findings reference a 2018 Federal Aviation Authority bulletin alerting operators to the possible disengagement of the fuel switch locking mechanism.

However, there’s no clear explanation of how this mechanical issue could have caused both switches to flip nearly simultaneously, the BBC reported.

The bulletin was an “advisory and not mandatory”, and therefore, inspections by Air India were skipped. The airline’s past maintenance included throttle module replacements in 2019 and 2023.

“However, the reason for the replacement was not linked to the fuel control switch,” the report said.

Until further investigation digs into whether this was human error or a rare mechanical malfunction, the cause remains unresolved.

Ahmedabad Air India crash report revealed: Key points

1. Pilot’s confusion

As per the cockpit voice recording, the pilot denied cutting-off the fuel. One pilot was heard asking “Why did you cutoff?” to which the other replied, “I did not do so,” suggesting a potential technical malfunction or inadvertent activation, the Times of India reported.

2. RAT deployed

The CCTV footage obtained from the airport showed the Ram Air Turbine (RAT) getting deployed during the initial climb immediately after the lift-off.

A Ram Air Turbine (RAT) is a small turbine that is installed in an aircraft and used as an alternate or emergency hydraulic or electrical power source.

As per reports, the RAT deploys from its stowed position when an aircraft experiences an engine failure or a loss of electrical power.

The AIBB report stated that both engines’ “N2 values” passed below the “minimum idle speed”, and the RAT hydraulic pump began supplying hydraulic power at about 08:08:47 UTC.