The deadly crash of London-bound Air India flight AI171 on Thursday, 12 June 2025, less than a minute after takeoff from Ahmedabad, has sparked speculation about possible causes for the first-ever Boeing Dreamliner accident.
With a preliminary report expected within a month according to international aviation rules, investigators from India, from the UK Air Accidents Investigation Branch (AAIB) and from United States’ National Transportation Safety Board (NTSB) are united in searching for an explanation for the deaths of 241 passengers and crew members, as well as at least 39 victims on the ground where the world’s second largest aircraft hit medical college accommodation.
In these situations, officials are careful not to conjecture. Evidence will be gathered from black box flight recorders about communications and flight data from the plane, as well as from witnesses, including the sole survivor. But, in the absence of information, news organisations and aviation analysts have begun to list factors the officials will be considering.
Mayday call
The pilot of AI171 is already known to have issued a mayday call—a fact which some say rules out a sudden disintegration or failure, perhaps caused by malicious interference or terrorism. Despite India being hit by a wave of costly bomb threats in 2024, Professor Philip Baum, an aviation security expert at Coventry University, told The Independent he agrees an attack of some sort is unlikely to be behind the crash.
2/The plane took off from Sardar Vallabhbhai Patel International Airport at around 1:39 PM local time.
— Jami (@expertwith_AI) June 23, 2025
Within just 40 seconds, the aircraft began descending rapidly and crashed into a densely populated
residential area—Meghani Nagar—hitting a hostel for doctors pic.twitter.com/nJktpdKwKP
Failure to gain altitude
What we do know is that the plane ceased gaining altitude just seconds after takeoff. Prof. Baum said it “seems likely” the issue could be put down to some kind of system failure affecting the engines’ ability to generate thrust.
Modern aircraft are built to be able to fly in case one engine fails and, in some cases, to be able to glide without power, witness the so-called Hudson River miracle where US Airways flight 1459 landed without loss of life after bird strikes took out both engines. Air Transat Flight 236 suffered a fuel leak, causing both engines to fail 65 nautical miles out of Lajes Air Base in the Azores, but pilots glided the aircraft there without power over 17 hairy minutes.
But if both engines failed immediately after takeoff the pilots would have had almost no chance to save the plane and its passengers. Whether that potential failure could have been mechanically in-built or be down to human error is another question. Peter Goelz, formerly of the US National Transportation Safety Board (NTSB), told press that inspecting the turbine wreckage would give investigators clues as to whether the engines were generating thrust when the crash occurred, or not.
Air India AI171 Plane Crash: What We Know Till Now
— Jami (@expertwith_AI) June 23, 2025
A THREAD 🧵
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A shocking tragedy unfolded in Ahmedabad yesterday. Air India flight AI171, a Boeing 787-8 Dreamliner bound for London Gatwick, crashed shortly after takeoff with 242 people on board pic.twitter.com/tQXY4pIVHC
Boeing’s automated thrust control
Boeing’s bespoke “thrust control malfunction accommodation” (TCMA) system is generating chatter in aviation circles. This software will automatically “correct” a thrust control malfunction, shutting an engine down to ensure that aircraft engines cease to operate at high power if they are not responding to a throttle command during takeoff, approach or landing.
Two fatal crashes involving Boeing’s 737 Max were caused by a flaw in another automated feature: the “manoeuvring characteristics augmentation system” (MCAS). Alongside recent manufacturing quality concerns, that history has prompted some to wonder if a similar flaw could have occurred with the TCMA.
At the time of writing, Boeing Dreamliners continue to fly, but India’s Directorate General of Civil Aviation (DGCA) has ordered checks on all Air India Boeing 787s fitted with GEnx engines, like those on Flight AI171, “with immediate effect”.
#ImportantUpdate
— Air India (@airindia) June 14, 2025
Air India is in the process of completing the one-time safety checks directed by the Indian aviation regulator, DGCA. These checks are being carried out on the Boeing 787 fleet as they return to India, before being cleared for their next operations. Air India has…
Bird activity
As mentioned above, bird strikes can take out aircraft engines, and did so fatally in South Korea in late 2024. The issue is a cause of enough concern to prompt bird activity detection systems to be installed around some airports.
Thol Lake and its nearby marshland, a haven for migratory birds, are under 30 km from Ahmedabad, and the Nalsarovar wetland bird sanctuary is twice that distance to the southwest. Closer is the Sabarmati River, also a known home to herons, egrets, ibises, kingfishers, and migratory species.
Most birds typically fly at under 150 metres for daily activities, below the 190-metre altitude reached by the plane. Although birds fly at altitudes many times higher than altitudes for migrating, the migration season around Ahmedabad is November to February.
Plane settings
Some commentators have pointed out that the Dreamliner’s wing flaps (the extendable panels which can be seen through plane windows moving downwards and retracting) might have been set wrongly, which could have caused AI171 to stall. The flaps not only increase drag, slowing aircraft on landing, but are deployed to increase lift on takeoff.
Alternatively, if the engine’s fuel supply had been inadvertently cut off, the engines would have failed. Information from the flight deck and black boxes will help as investigators try to ascertain what went wrong.
