Air India flight 171 had been airborne for just 11 seconds when a routine take-off suddenly became an irrecoverable disaster.
Captain Sumeet Sabharwal radioed the ground to say: “Mayday…no thrust, losing power, unable to lift!”
Over the next 19 seconds the Boeing Dreamliner steadily lost altitude and drifted to the ground before crashing into buildings, killing almost everyone on board and dozens on the ground as air traffic controllers watched helplessly.
Exactly what caused flight 171 to fall back to Earth will be the subject of an investigation that might take months, with bird strikes and mechanical failure among the possibilities that will be looked into.
On Thursday night the confirmed death toll had reached 290, with only one passenger – a 40-year-old Briton – known to have survived the tragedy.
The video footage shows it appearing to suffer a catastrophic loss of lift as it falls to the ground, still in its nose-up take-off angle, unable to stay airborne.
The Boeing 787-8 Dreamliner never reached the right rate of climb during its short trajectory.
In those fateful moments, the highly experienced pilot and Clive Kundar, his co-pilot, alerted ground control to the fact that they were in terrible trouble, but after reaching a maximum altitude of barely 400ft, all contact with the aircraft was lost.
Incredibly, one passenger survived the crash. Vishwash Kumar Ramesh, a 40-year-old Londoner, who was in seat 11A and is now in hospital.
Moments earlier, the departure lounge of Ahmedabad airport had been the usual mix of excitement and anticipation as passengers returned home from holidays, headed off on adventures or looked forward to family reunions before their scheduled 9hr 50min non-stop flight to London Gatwick.
They included married couple Fiongal and Jamie Greenlaw-Meek, from London, who passed the time by recording an Instagram video in which Fiongal smiled and rolled his eyes as Jamie said they were about to board a “10-hour flight back to England”.
Also waiting in the lounge was Adnan Master, a 30-year-old east Londoner who had been visiting relatives in India, the Lalgi family, from Wembley, and Raxa Modha, from Northamptonshire. Others were flying home to Leicester.
Local passengers at Sardar Vallabhbhai Patel International Airport had noticed that at least one VIP was among them – Vijay Rupani, the former chief minister of the Gujarat region, in which the airport is situated.
Their Air India aircraft was being cleaned, fuelled and readied for boarding. The passengers may have been reassured by the fact that it was a Boeing 787-8 Dreamliner, a type of jet that had never been involved in a fatal accident.
The weather was ideal for flying: sunny and dry, with an air temperature approaching 40C.
Everything appeared normal as the passengers boarded and the aircraft taxied towards runway 23 shortly after 1.30pm local time.
On board were 230 passengers, including 53 Britons, 169 Indians, seven Portuguese and one Canadian, as well as 12 crew. Eleven of the passengers were children.
In the cockpit, Captain Sumeet Sabharwal and First Officer Clive Kundar, who boasted more than 9000 hours of flying time between them, increased power and comfortably reached takeoff speed, clocking 174 knots according to data recorded on the ground.
What happened next was captured on CCTV footage that will form crucial evidence for air crash investigators.
The 11-year-old aircraft became airborne at 1.38pm and appeared to take off normally, then climbed for 11 seconds before it stopped gaining altitude.
For the next 19 seconds, it gradually lost altitude, drifting slightly from starboard to port, its wings remaining level as the crew fought to keep it in the air.
In those fateful moments, Sabharwal issued his mayday call, but after it reached a maximum altitude of barely 400ft above the runway, all contact with the aircraft was lost.
Video footage shows it suffering a catastrophic loss of lift as the pilot said he was losing power. Then it glided down to the ground, still in its nose-up take-off angle, and after disappearing behind trees in the camera’s line of sight it crashed just a few hundred yards from the end of the runway in a fireball that could be seen for miles around.
Dr Jason Knight, of the University of Portsmouth’s School of Electrical and Mechanical Engineering, said a cloud of dust that can be seen on the video just as the aircraft is taking off could be significant.
He said: “The aircraft could fly perfectly well on one engine. But without any power, the pilot has no choice but to do an emergency landing.
“I’m not sure, but it appears as though the cloud of dust could be from the engines as they both fail. This could be for a number of reasons, but in my opinion, the most likely is a bird strike in both engines.”
The aircraft had crashed in a built-up suburb called Meghani Nagar that includes the campus of a medical college, the BJ Medical College, as well as homes and offices.
Raju Prajapati, a resident of the Shahibaug neighbourhood, just a few hundred metres from the crash site, told the Telegraph: “We heard a huge explosion and rushed out of our homes.
“There were thick plumes of black smoke rising into the sky. People were shouting and running in all directions.”
Another man at the scene said: “I was sitting at home, there was a loud noise, it felt like an earthquake. I came out and saw smoke, I didn’t realise it was a plane crash, then I came here and I found out and I saw the crashed plane – there were many bodies lying on the ground.”
Inside the medical college, students were sitting down to lunch when the aircraft clipped the dining room. One photograph taken inside the building showed abandoned meals still on tables and a large piece of the aircraft’s tail section jutting into the end of the room.
A woman called Ramila said: “My son had gone to the hostel during lunch break, and the plane crashed there. My son is safe, and I have spoken to him. He jumped from the second floor, so he suffered some injuries.”
More than 20 students were taken to hospital, with pictures showing wreckage, including the landing gear, embedded in the building.
As rescuers rushed to the scene, it seemed impossible that anyone had survived the crash and the fire that followed.
Incredibly, one passenger not only survived but was able to walk away from the wreckage unaided.
Londoner Vishwash Kumar Ramesh, 40, was in seat 11A, a window seat in the first row of the main cabin, directly behind one of the aircraft’s doors. He was filmed, bloodied but steady, walking to a waiting ambulance.
Remarkably, he appeared to have suffered only minor injuries and was later able to speak to his family from his hospital bed.
The front portion of the fuselage, including the area where Ramesh had been sitting, was one of several large parts of the aircraft that were left lying in what had been busy streets near the medical centre.
One of the aircraft’s wings, with its registration number VT-ANB clearly visible in large red letters, lay largely intact on the ground, as did the tailfin with its distinctive Air India logo.
Evidence of the individual lives lost in the tragedy was strewn everywhere.
One building had piles of clothes on ledges where they had burst out of passengers’ suitcases in the crash; nearby charred suitcases and other belongings were mixed together with twisted metal and wiring looms from the aircraft. Charred bodies were also visible among the wreckage.
Tim Atkinson, a former accident investigator, told the BBC it was “probably the most complex scene that I’ve seen pictures of”.
He said: “This is going to be a very lengthy and extraordinarily difficult and awkward crash site for those working on it to be involved in.”
Inevitably, lives had also been lost on the ground. The Indian authorities said at least 290 people were known to have died, meaning around 50 were killed on the ground.
At the Civil Hospital in Ahmedabad, staff formed a long line with gurneys covered in white sheets, ready to receive the remains of the dead, while relatives of those on board gathered, desperate for news.
A man in his late 40s broke down near the hospital gates, pleading with officials to let him through.
He said: “My sister and brother-in-law were on the flight. Their seats 110 and 111 were confirmed.
“Our niece called from London to say: ‘Mumma and Papa were on the plane.’
“We’re from Naroda and have been moving from one checkpoint to another for over an hour and a half. No one is letting us enter the hospital or even wait nearby. We haven’t come here for a picnic, we’ve lost our family.”
Mahendra Vasandiya, 65, another relative of passengers on board, stood quietly among the crowd.
He said: “My younger brother and his wife were travelling to London to see their daughter.
“I still have no information about them. No one is telling us anything.”
Nearby, a woman clutched her phone, struggling to hold back tears.
She said: “My sister-in-law and her husband were on that plane.
“Their daughter called me in tears from the UK to say they were coming to visit her. I didn’t even know they were flying today.”
At Gatwick, where the flight had been scheduled to land at 6.25pm, a reception centre was set up for relatives of those on board.
The airport said “information and support will be provided” for those desperate for news of their loved ones.
Downing Street warned the public to be prepared for news of significant loss of British lives.