What exactly happened will only be revealed by a detailed investigation, but the moments after take-off can be the most challenging in aviation.
It is almost impossible to definitively establish what caused the disaster based on videos of the plane's brief flight, but the BBC has spoken to aviation experts to find out what might have caused the crash. They speculated on a few potential causes:
Rare double engine failure: Footage showed the plane flying low and the plane was airborne for 30 seconds. "There would have been no time for [the pilot] to react if he lost both engines," one pilot tells us.
Bird strike: Another possibility raised by some experts in India is a bird strike. Experts and pilots familiar with Ahmedabad airport have told the BBC that it is "notorious for birds".
Plane flaps: Three experts who spoke to BBC suggested that the disaster may have occurred as the aircraft's flaps were not extended during take-off - though other pilots and analysts have challenged this.
Desperate wait for DNA test results in Ahmedabad hospitalpublished at 22:45 British Summer Time 12 June
22:45 BST 12 June
The BBC's Samira Hussain says family and friends of a number of the engers who were on board the crashed plane have gathered in Ahmedabad's hospital for DNA tests to help identify their loved ones.
'It took hours to make sense of the chaos'published at 22:26 British Summer Time 12 June
22:26 BST 12 June
Zoya Mateen Reporting from Ahmedabad
Warning: This post contains distressing details.
A police official who wanted to stay anonymous has told the BBC that all the bodies and their remains have been removed from the site of the crash.
“It took hours to make sense of the chaos. And it’s going to take many more hours to completely clear up the site,” he says.
The official adds that apart from “one or two lucky ones”, everyone’s dead.
“And it’s not just those on board,” he continues. “The building the plane crashed on, the hospital, was full of medical students. Many have died from our understanding.”
What more have we heard?published at 22:02 British Summer Time 12 June
22:02 BST 12 June
It's night time now in India, where loved ones of those who lost their lives in Thursday's fatal crash wait to claim their bodies outside Ahmedabad's Civil Hospital.
Let's take a look at the latest:
Air India have confirmed that there was one survivor, named as British national Vishwashkumar Ramesh, who is recovering in hospital
The other 229 engers and 12 crew were killed in the crash, the airline says
A rescue operation at the crash site in Ahmedabad has been completed, India's civil aviation ministry says
As a reminder, at least 50injured medical students were taken to hospital earlier today after the plane crashed into a doctors' hostel in the western Indian city.
India’s Federation of All India Medical Association said five students were missing, but we are yet to hear a further update.
Latest photos from crash site in Ahmedabadpublished at 21:48 British Summer Time 12 June
21:48 BST 12 June
Indian officials say they have now completed their rescue operation at a vast plane crash site in Ahmedabad.
The operation continued well into the night - here are some of the latest photos showing the sheer devastation in the western Indian city.
Image source, Reuters
Image caption,
Rescue teams combed through the wreckage in Ahmedabad's residential area by the airport where the London-bound Air India flight crashed just seconds after take-off on Thursday
Image source, Reuters
Image caption,
A number of buildings - like this one - were badly damaged, with twisted fragments of the aircraft seen stuck between the floors
Image source, Reuters
Image caption,
The wreckage of what looks like one of the plane engines ended up laying on the street near a gutted building
Disaster force officials still pouring in and out of the crash sitepublished at 21:26 British Summer Time 12 June
21:26 BST 12 June
Zoya Mateen Reporting from Ahmedabad
It's coming up 02:00 (21:30 BST) here in Ahmedabad but the city is buzzing with activity.
Legions of police vans patrol the streets. A steady stream of disaster force officials pours in and out of the site of the crash, which is still being cleared.
A gaggle of journalists remain perched near the barricades erected around the spot where the crash took place - they are not being allowed to go any closer to the debris.
While the crowds have gone down, there are still civilians around, trying to help in way possible, from serving tea to policemen and helping clear the trash from the streets.
What’s most striking, however, is the smell of smoke and burnt metal that lingers in the air, hours on from the crash.
UK Foreign Secretary Lammy chairs emergency Cobra meetingpublished at 21:19 British Summer Time 12 June
21:19 BST 12 June
Helen Catt Political correspondent
The BBC understands that Foreign Secretary David Lammy has chaired a meeting of the government's emergency committee, Cobra, in response to the Air India plane crash.
Relatives wait as authorities work to identify bodiespublished at 20:56 British Summer Time 12 June
20:56 BST 12 June
Ishadrita Lahiri, Seraj Ali, and Shaili Bhatt Reporting from Ahmedabad
Image source, EPA
It's approaching 1:30 in India, but it does not seem so outside the post-mortem room at the Civil Hospital in Ahmedabad.
Families and friends of those who’ve lost their lives in the crash wait to claim their bodies, but identification has become a difficult task. Authorities are trying to use DNA sampling, but the process is taking time.
Outside the hospital, the BBC’s team meets T. Thanglingo Haokip, whose cousin, Singson, was cabin crew on Air India flight 171.
Speaking to the BBC, Haokip explains that he has been trying for hours to get some information about Singson but has been unsuccessful.
He says: “Her parents are worried. She only has a mother, her father ed away. Her brother has cancer. She was the only breadwinner in the family. Her family was wholly dependent on her."
There’s been a steady stream of bodies coming into the hospital for post-mortems after the crash.
“Ever since the bodies started coming in, we’ve been examining them. We are exhausted. We have lost track of time," a doctor in the hospital tells us.
Official death toll to be released once DNA testing complete, minister sayspublished at 20:09 British Summer Time 12 June
20:09 BST 12 June
DNA testing of the victims of the plane crash is currently under way, a press release from Indian Home Affairs Minister Amit Shah says.
Shah, who has now visited the crash site after earlier speaking to survivors in hospital, says that only once DNA testing is complete will an official death toll be released.
"On behalf of the government of India, the government of Gujarat, and the prime minister, I express deep condolences to all those who lost their lives," the statement reads.
'It sounded like a bomb blast'published at 19:53 British Summer Time 12 June
19:53 BST 12 June
Image source, Getty Images
Warning: This post contains distressing details.
BBC correspondent Roxy Gagdekar has been speaking to people at the scene of the crash in Ahmedabad.
“We heard a loud noise. It sounded like a bomb blast,” one man says.
“There was smoke and fire. I said, ‘let's go and see’. Someone said that the plane had fallen,” he says, adding: “As soon as I got there, I saw that the plane was on fire. There were three people lying nearby.”
Another man, a taxi driver who was working nearby, says: “When I saw the smoke, I ran there. I couldn't go near the plane, there were dead bodies outside.”
“The plane’s wing had come out on the main road. There was smoke everywhere,” he says.
Investigators will be searching for the plane's black boxespublished at 19:05 British Summer Time 12 June
19:05 BST 12 June
Image source, EPA
Image caption,
Contrary to the name, black boxes are often brightly coloured to make them easier to find
The answer to what went wrong for Air India Flight 171 may lie in the plane's black boxes - small but sturdy electronic data recorders.
Planes generally carry one to record sound from the cockpit so that investigators can hear what the pilots are saying and listen out for any unusual sounds that may give them a lead. A second also records flight data, like altitude and speed.
Typically, black boxes are kept in the tail of the plane, thought to be the section that is typically least damaged in the event of a crash.
We're yet to hear whether the black boxes for Flight 171 have been recovered, but if they are, don't expect immediate answers - it can sometimes take days or weeks to analyse the data.
Boeing CEO offers condolences to the victims and familiespublished at 18:56 British Summer Time 12 June
18:56 BST 12 June
Image source, Reuters
Boeing President and CEO Kelly Ortberg has now issued a statement about the crash, saying his thoughts are with the victims.
"Our deepest condolences go out to the loved ones of the engers and crew on board Air India Flight 171, as well as everyone affected in Ahmedabad," he says.
Ortberg says he spoke with Air India Chairman Natarajan Chandrasekaran "to offer our full ", and reiterates that Boeing will an investigation led by India's Aircraft Accident Investigation Bureau.
Air India plane crash - what we know so farpublished at 18:45 British Summer Time 12 June
18:45 BST 12 June
Image source, Reuters
Image caption,
The wreckage of the tail section of the crashed Air India plane seen stuck in a building in Ahmedabad
Here's a quick recap of what we know at this point about the Air India plane crash at Ahmedabad's airport:
The London-bound Boeing 787-8 Dreamliner with 242 people on board crashes into a residential area just moments after take-off at about 13:38 local time (09:08 BST) on Thursday
Dramatic footage later emerges showing the aircraft taking off before slowly coming down in a built-up area. Plumes of black smoke are then seen rising high into the sky after an explosion upon impact
Local police say 204 bodies have since been recovered from the crash site - it's not known how many of those victims were on the plane, or were on the ground when the plane crashed
Ahmedabad's police chief tells Indian media there is one survivor from the plane - he is reported to be a British national named Vishwashkumar Ramesh
There were 169 Indian nationals, 53 Britons, seven Portuguese nationals and one Canadian on the flight
At least 50 injured medical students are being treated in hospital after the plane crashed into a doctors' hostel in the western Indian city
A search operation is continuing overnight at the massive crash site
Teams of US and UK specialists are heading to India to assist with the investigation
Stay with us, as we'll continue bringing you all the latest developments as well as photos and videos - as soon as we get them.
This really just feels like an apocalyptic scenepublished at 18:37 British Summer Time 12 June
18:37 BST 12 June
Yogita Limaye South Asia and Afghanistan Correspondent, reporting from Ahmedabad
Media caption,
BBC journalist shows devastation on the ground after India plane crash
What strikes you as soon as you enter the area where the crash happened is this kind of burning smell in the air, which grows stronger and stronger.
Where we are, there are still very acrid fumes. In front of me I can see the fire brigade, which is pointing a giant hose towards one of the buildings to put out the fire that is still burning, blazing inside.
There's a charred tree but I can see parts of it right at the top still smoking. I can see sparks from there and right next to me, there's also a fallen tree, which is also smoking.
Ever since I've walked in, I've just seen hundreds of rescue workers, scores and scores of police officers everywhere, ambulances.
This is a massive plane that crashed - a Dreamliner aircraft - but you've got to be on the ground to just see the scale of devastation.
The scale of the tragedy is just truly, truly, much more massive than perhaps what I had imagined when I got here.
All you can see is charred bits and pieces, metal bits, bits of concrete blocks, bricks, strewn all about.
I can see what appear to be parts of charred bits of the body of a plane, but I don't think anybody can be sure of what that was. This really just feels like an apocalyptic scene.
I'm not sure I've ever seen a scene of such devastation from one incident which looks like this before.
UK investigation team dispatched to India, PM sayspublished at 18:28 British Summer Time 12 June
18:28 BST 12 June
Image source, PA Media
UK Prime Minister Keir Starmer says the news from India following today’s crash of a plane bound for London Gatwick in Ahmedabad is “absolutely devastating” and he “speaks for the entire country in saying our thoughts are with everyone involved”.
Speaking to broadcasters, he says a UK team had been dispatched to Gujarat to the investigation, and urges families and friends of anyone affected to the Foreign Office.
“Our hearts and our thoughts are absolutely with the friends and families of everyone affected who’ll be absolutely devastated by this awful news”, he says.
Indian minister meets British survivor in hospitalpublished at 18:15 British Summer Time 12 June
18:15 BST 12 JuneBreaking
Indian Home Affairs Minister Amit Shah has met people injured in the crash - including the man who seems to be the only survivor from the plane itself, British man Vishwashkumar Ramesh.