A cockpit voice recording from the doomed Air India crash showed one pilot asking another why he cut off fuel supply to the engines. 

Air India Flight 171 from Ahmedabad to London Gatwick crashed on June 12, with all but one of 230 passengers killed. 

This morning, India’s Aircraft Accident Investigation Bureau (AAIB) released a preliminary report into the crash. 

The aircraft achieved its maximum recorded airspeed soon after takeoff. 

Then, two engine fuel cutoff switches transitioned from “run” to “cutoff” within a second of each other. 

“In the cockpit voice recording, one of the pilots is heard asking the other why did he cut off,” the AAIB report said. 

“The other pilot responded that he did not do so.” 

About 22 seconds later, one of the pilots transmitted “MAYDAY MAYDAY MAYDAY”. 

As the aircraft was losing altitude, it initially made contact with trees before hitting a chimney and a medical college. 

Downloaded flight data contained about 49 hours of flight data and six flights, including the crashed flight. 

“The take-off weight was within allowable limits for the given conditions,” the report added. 

“No significant bird activity is observed in the vicinity of the flight path.” 

The report said the aircraft started to lose altitude before crossing the airport perimeter wall. 

Forensic experts and officials searching for evidence at the Air India Plane crash site on June 13. Photo / Raju Shinde, Hindustan Times via Getty Images 

The flap handle assembly was found to be consistent with a normal takeoff flap setting and the landing gear lever was in the “down” position. 

There were 230 passengers on board, with 15 in business class and 215 in economy class, including two babies. 

The Boeing 787-8 was manufactured in 2013 and both its engines in use were installed this year. 

The aircraft and its engines complied with all applicable airworthiness directives, the report said. 

And there were no reported defects pertaining to the fuel control switch on the aircraft. 

Experienced pilots, engineers, aviation medicine specialist, aviation psychologist and flight recorder specialists were being used as subject matter experts. 

Both engines were retrieved from the wreckage site and quarantined at a hangar in the airport. 

“Complete analysis of postmortem reports of the crew and the passengers is being undertaken to corroborate aeromedical findings,” the report added. 

At this stage of investigation, there are no recommended actions to Boeing 787-8 and/or General Electric GEnx-1B engine operators and manufacturers. 

The investigation continues. 

Air India’s chief executive is Christchurch-born Campbell Wilson.