A BOMBSHELL new video proves what led to the Air India plane to crash and burn just after takeoff, an aviation expert has claimed.

In the mean time, the second black box containing key cockpit voice recordings has been found – expected to reveal the pilots’ panic as the plane went down.

The “game-changer” new footage reveals in greater detail the plane sinking through the sky and exploding in a fireball, k.il.l.ing all but one of the 242 passengers plus more on the ground.

According to commercial airline pilot Steve Schreiber, known for analysing air disasters, it proves that the Gatwick-bound Boeing 787 lost power immediately after takeoff.

Per the pilot, he has spotted a detail in the video which reveals the Dreamliner suffered a “dual engine failure” before the worst aviation disaster in more than a decade.

Initially Captain Steve believed a simple error in the cockpit was to blame, possibly related to the landing gear which did not retract.

However, after reviewing the HD clip, Steve is convinced that something caused both of the engines to cut out.

He pointed out a “protrusion on the belly of the aircraft”, underneath which is a “little grey dot”.

According to Steve, this is evidence of the Ram Access Turbine (RAT) deploying on the plane, which failed to climb more than 450ft.

He said: “Many aeroplanes have it. It is just behind the wing on the right side of the aeroplane, there is a little door that holds it in.

“It looks like a little Evinrude motor, it’s a little two bladed prop.

“The purpose is to provide electrical and hydraulic pressure for the aircraft on an extreme emergency.”

Steve explained there are three things which could led the RAT to deploy on a 787: “A massive electrical failure, a massive hydraulic failure, or a dual engine failure.”

He also explained that RAT make a “distinctive sound” like a single-propeller plane, which can be heard in the video.

Steve concluded: “It is evidence for us it was dual engine failure, most likely. It could have been electrical issue, it could have been hydraulic issue, it could have been either one of that.

“But I think the fact the aeroplane is mushing out the sky gives the idea it was a dual engine failure.”

Officials combing the crash site have found the second black box, which will let them reconstruct what happened second-by-second.

It holds the data from the Cockpit Voice Recorder (CVR) – which captured all cockpit audio including radio transmissions, pilot conversations, warning alarms and ambient mechanical sounds.

Planes usually carry two black boxes, which are small but tough electronic flight data recorders.

One records flight data, such as altitude and speed, whilst the other monitors the cockpit sound.

The first was recovered from a rooftop near where the plane came down just 28 hours after the crash.

We already know that the pilot, Captain Sumeet Sabharwal, made a desperate mayday call to air traffic control in the moments before the disaster.

He cried out: “‘Thrust not achieved […] falling […] Mayday! Mayday! Mayday!”

The two pilots then wrestled for 17 seconds with the controls as the jet sank through the air before careening into the buildings below.

Sabharwal had 22 years of experience and had racked up 8,200 in the air.

The plane gained just a few hundred feet of altitude when the power apparently cut out, killing more Brits than any air disaster since 9/11.

Despite more than 270 people dying in the catastrophe, the pilot has been credited with saving “dozens of lives”.

Sabharwal diverted the jet at the last second to avoid slamming into a three-storey apartment building, according to locals on the ground.

All 18 families in the three-storey building under the flight path are convinced they owe their lives to Captain Sumeet Sabharwal.

He managed to divert the plane towards a patch of grassland.

The locals raced from their homes in Ahmedabad when a fireball from 90 tons of aviation fuel ignited as the plane slammed into the ground.

The aircraft obliterated the top two floors of a disused four-storey military building.

But the fire tore through the college’s hostel, killing dozens of students and staff who were having lunch in the canteen.