FEARS are mounting that the doomed Air India flight was a pilot suicide – as an aviation expert claimed there was a vanishingly small chance the fuel was cut by accident.

Ex-pilot Terry Tozer told The Sun why it was extremely likely that the fuel switches were cut off intentionally – as a new preliminary report revealed the final moments inside the cockpit.

He explained why the plane’s lock mechanism meant it was incredibly unlikely the fuel was cut off accidentally.

Tozer said: “The fuel cutoff switches were actioned shortly after lift off from RUN to CUTOFF.

“And that implies that somebody did that as a conscious human action, because so far as we understand, these switches have a lock mechanism.”

He added: “They have to be lifted in order to be moved. Otherwise they lock in position.”

The claims come after the preliminary report on Saturday which indicated there may have been human error during the final moments of the doomed flight.

Two major commercial pilots’ associations rejected claims that human error caused the Boeing to crash and kill 241 people on board and 19 on the ground.

But aviation experts, like Tozer, say the evidence points to deliberate action – as speculation continues to grow that the crash was caused by a suicide attempt.

Tozer also explained another piece of evidence which strongly ruled out an electrical or mechanical fault.

He said: “The fact that the fuel cutoff was initiated first with one engine and then the other… kind of implies a conscious lifting of a switch – moving it and lifting it.”

The expert said that unless somebody could prove a “weird electromechanical process” caused the switch to move without human intervention, then all evidence indicated that “somebody lifted and moved one switch followed by the other”.

And he said the chance somebody could prove the switches were faulty was now “vanishingly small”.

He explained: “I find it hard to believe that that something you would do by accident.”

But he stopped short of speculating why the pilot may have chosen to do this.

“And of course, that opens another whole can of worms as to why somebody would do that,” he said.

He also told how the report was “probably trying to avoid deliberately pointing a finger” at either of the pilots by not naming which one said “why did you cutoff” in response to the fuel cutoff switches moving.

“The full report will basically come up with final conclusions,” he said, adding that not naming them specifically indicated investigators were “very circumspect”.

He added: “But of course, if the locking mechanism didn’t actually function on this aircraft, you can’t entirely rule out the fact that someone inadvertently touched them and they flicked off.

“Having said that, I can’t see why any pilot would have their hands anywhere near the area where these switches are located.”

He continued: “The first officer was flying the aircraft. Whose hands would have both been on the control column?

“The captain would have been monitoring what was going on. So he had his hands free.”

He said that another pilot in India speculated that the pilot committed suicide – but said that this statement was “rather presumptuous because we simply don’t know”.

The claims came as it was revealed that Air India’s CEO backed the doomed fight’s pilots in a leaked memo, Reuters reported.

Airline CEO Campbell Wilson said the probe into the horrific crash was far from over and warned it would be unwise to jump to any conclusions.

He said in the memo: “The release of the preliminary report marked the point at which we, along with the world, began receiving additional details about what took place.

“Unsurprisingly, it provided both greater clarity and opened additional questions.”

Wilson added: “The preliminary report identified no cause nor made any recommendations, so I urge everyone to avoid drawing premature conclusions as the investigation is far from over.”

Key findings of the report:

• Dual engine shutdown – fuel cutoff switches moved from ‘RUN’ to ‘CUTOFF’
• Confusion between pilots – cockpit audio confirms one pilot asked ‘why did you cutoff’, the other replied ‘I didn’t’
• RAT deployed – as seen in CCTV footage before the crash
• Engine relight attempted – fuel switches were found returned to the “RUN” at crash site
• 32 seconds – the time the aircraft was airborne before it crashed
• Thrust levers mismatch – Thrust levers found at idle but black box data shows takeoff thrust was still engaged
• Fuel test pass – fuel was clean without any contamination
• Normal take-off set-up – Flaps and landing gear correctly configured
• No bird activity – clear skies, good visibility, light winds
• Pilot credentials clear – both medically fit and rested
• No sabotage detected – although FAA alerted over a known fuel switch vulnerability not checked by Air India
• Aircraft loading – the flight was within weight and balance limits

The Boeing 787 Dreamliner en route to London Gatwick from Indian Ahmedabad began to lose thrust and sink shortly after takeoff,the report released by India’s Aircraft Accident Investigation Bureau (AAIB) said.

The memo also said the preliminary report found no mechanical or maintenance faults, and that all required maintenance had been carried out.

The claims and leaked memo also came as it was revealed the doomed flight’s captain was considering quitting early after his mum’s death.

Flight AI171 was led by Captain Sumeet Sabharwal, who was reportedly just months away from retirement, his neighbours revealed.

He was looking to retire early and take care of his 92-year-old father Pushkaraj Sabharwal – a former Indian civil aviation official – who became alone after his wife’s death.

Savitri Budhania, who lives close to Captain Sabharwal’s house, said she once told him that “your father is too old to be living alone”.

To which the pilot replied: “Just one or two more flights… then I’m going to just be with Papa.”

A leading aviation expert in India also told The Telegraph that Captain Sabharwal suffered from mental health issues and depression – and had taken time off in the last few years following his mum’s death.

Captain Mohan Ranganathan, a former instructor pilot of Boeing 737, said: “I have heard from several Air India pilots who told me he had some depression and mental health issues.

“He had taken time off from flying in the last three to four years.”

Crash investigators are now said to be probing the medical records of the Sabharwal amid claims he suffered from mental health problems.

The Boeing 787 Dreamliner with 242 passengers on board – including 53 Brits – smashed into a doctors’ hostel in Ahmedabad in the west of India.

The plane was headed to London Gatwick when it crashed just seconds after take-off, killing all but one passenger.