An aviation expert believes the co-pilot on Air India flight AI171 pulled the plane’s wing flaps instead of retracting the landing gear, causing the plane to crash.

Commercial airline pilot and YouTuber Captain Steve, who analyzes plane crashes and close calls, gave his theory on the incident which killed 241 people on board.

The London-bound 787 Dreamliner began losing height moments after take-off and crashed in a fireball over a residential area in the Ahmedabad, Gujarat.

Steve said he suspected there had been an exceptionally simple error in the cockpit when the co-pilot was asked to retract the landing gear, with devastating consequences.

He said: ‘Here’s what I think happened, again folks this is just my opinion. I think the pilot flying said to the co-pilot said ‘gear up’ at the appropriate time.

‘I think the co-pilot grabbed the flap handle and raised the flaps, instead of the gear. If that happened, this explains a lot of why this airplane stopped flying.’

Steve said that the flaps being raised would cause the flight to lose airspeed and altitude quickly, something he thinks the pilot would have struggled to control.

He explained his theory by saying the 787’s composite wings would normally bend during take off as lift forces take it into the air.

But the Air India plane appears to show no such bending, amid widespread speculation the flaps which help lift the plane off had accidentally been retracted.

Only one of the 242 people on board survived and as many as 24 people on the ground were also killed in what was the world’s worst aviation disaster in a decade.

Commercial airline pilot and YouTuber Captain Steve, who analyzes plane crashes and close calls, gave his theory on the incident which killed 241 people on board

Footage showed the moments before the Air India plane came down in Ahmedabad

It remains unclear what caused Thursday’s tragedy, with mechanical failure or pilot error among the possible causes that investigators will now work to identify.

Among those believed to have died is Captain Sumeet Sabharwal, the pilot operating the Boeing 787.

Mr Sabharwal, who had 8,200 hours of experience, was named as the pilot of the Boeing 787 Dreamliner.

First Officer Clive Kunder, from Mumbai and who was co-piloting, had logged 1,100 of flying hours and completed his training at the Florida-based Paris Air Flight School.

The sole survivor Vishwash Kumar Ramesh, 40, has since been visited by Indian Prime Minister Narendra Modi in hospital.

Mr Ramesh told DD News, ‘I still can’t believe how I survived’, as he spoke from his hospital bed on Friday.

He told the broadcaster the plane felt like it was ‘stuck in the air’ shortly after take-off before lights began flickering green and white – adding: ‘It suddenly slammed into a building and exploded.’

He said: ‘I still can’t believe how I came out of it alive. For a moment, I felt like I was going to die too.

‘But when I opened my eyes and looked around, I realized I was alive. I still can’t believe how I survived.’

The sole survivor Vishwash Kumar Ramesh, 40, has since been visited by Indian Prime Minister Narendra Modi in hospital, seen here

Among those believed to have died is Captain Sumeet Sabharwal, left, and First Officer Clive Kunder, right

At least 24 people were killed on the ground, officials said, after the airplane landed on a canteen building where students were having lunch.

The flight data recorder was recovered from the wreckage on Friday, in what will likely lead to clues about the cause of the accident.

The plane’s digital flight data recorder, or black box, was recovered from a rooftop near the crash site and India’s Aircraft Accident Investigation Bureau said that it had begun its work with ‘full force.’

The black box recovery marks an important step forward in the investigation, Civil Aviation Minister Ram Mohan Naidu said in a social media post.

U.S. participants in the investigation will include people from the NTSB, FAA, Boeing and General Electric.