Experts examine what could have gone wrong

Hindustan Times

12-06-2025

The Boeing 787 aircraft that crashed soon after taking off — it spent all of 33 seconds in the air — from Ahmedabad's Sardar Vallabhbhai Patel International Airport has left the aviation industry stunned, with experts examining what could have gone wrong with the 11-year-old aircraft carrying 230 passengers and 12 crew.
Video evidence from a surveillance camera at the airport showing the aircraft's final moments provide some crucial clues about the accident sequence. It reveals the plane following a normal take-off trajectory before suddenly losing its ability to climb. Moments later, it slowly descends into the horizon and erupts into a ball of fire.
According to officials aware of the matter, a Mayday call was issued by the pilots shortly after take-off.
HT spoke to multiple experts on the possible scenarios that may have unfolded in the moments before the crash and while each of them cautioned that early clues were insufficient to draw conclusions, they agreed that the profile of the flight in its final moments — maintaining a nose-up attitude while descending — was consistent with sudden, severe power loss.
'A B787 aircraft has extremely powerful engines. It is hard to guess what went wrong. It looks like the pilot could not get adequate thrust and realised the issue immediately after take-off,' said Amit Singh, aviation safety expert and founder of Safety Matters Foundation.
What led the plane to lose power would likely be at the centre of the investigation, said another expert. 'While nothing can be said by merely looking at the video, it could be possible that the crash was because both engines stalled. Investigations will reveal what led to the situation,' said Sam Thomas, president of the Airline Pilots Association of India (ALPA). That's an extremely rare event on a 787, with a probability of a 1 in billion flying hours.
A third expert, Mohan Ranganathan, agreed that from the visuals, that it appeared there was 'a loss of thrust and compressor failure' — referring to the scenario when not enough air enters the engine, reducing thrust.
One of the other scenarios that HT brought up was a bird strike which can potentially disable one, or in the extremely rare case of the December 2024 crash of Korea's Jeju Air Flight 2216, both engines.
Thomas said the possibility was extremely slim. 'It is highly unlikely that a flock of birds hit both the engines leading to the crash,' he said.
Ranganathan, however, added that 'during monsoons, bird activity around the airport increases and the airport is known for flocks of birds flying in its vicinity.'
The runway surveillance footage did not have the typical signs of a bird hit, where flames or smoke is momentarily seen from an engine when birds are ingested.
Another scenario involves determining what some experts said was a peculiar configuration of the plane in its final moments. In another video shot by a bystander with a closer view of the crash, the plane's landing gear is still extended but its flaps – a sort of wing deployed to generate lift – are retracted. 'That should not have been the case at all,' said Singh.
A senior pilot, who asked not to be named, too drew attention to the landing gears having not been retracted as a crucial indicator. 'Landing gear is retracted after an average of 35-100 ft of climbing since the aircraft achieves what is known as a positive climb rate. As per Flightradar24, the aircraft achieved a height of 650 ft. The Ahmedabad airport is at an elevation of 180ft which essentially means aircraft achieved a height of around 400 ft. This indicates that something more systemic could have happened and was detected immediately after take-off,' said this person, suggesting the pilots may immediately have planned for a return.
Other scenarios, experts said, would require investigation of whether there were problems with the fuel or the take-off weight, both of which could hamper an airliner's ability to climb.
Aviation expert Vipul Saxena said that the aircraft would have had 100,000 litres of fuel for its non-stop flight to London.
Saxena noted that the aircraft took off in clean configuration but faced challenging conditions. 'The aircraft experienced strong cross winds at atmospheric temperatures of above 30 degrees, which in itself could have caused certain amount of loss of lift,' he said.
He highlighted the unusual landing gear configuration as a critical factor. 'Till the aircraft crashed, the undercarriage were still not retracted, which was very unusual and which too would have required more lift and, thus, more engine power,' he explained.
The expert suggested a possible control system failure contributed to the aircraft's inability to recover. 'The situation seems complicated since the aircraft started sinking in a take-off attitude, which points to failure of one of the controls (may be flaps or elevators) that increased descent in take-off attitude,' Saxena said.
The accident has raised broader questions about aviation safety standards. 'The 787 has been in revenue service with Air India under government management for 15 years, and it has been one of the safest Gen5+ passenger airliners ever made,' said Mark D Martin, MRAeS and CEO of Martin Consulting. 'It's shocking that, with qualified crew having extensive experience in flying hours and maintenance, we see a catastrophic incident such as this.'
The pilots operating the aircraft were Capt Sumeet Sabharwal and First Officer Clive Kundar. According to the Directorate General of Civil Aviation, Capt Sabharwal was a line training captain with 8,200 hours of flying experience, while the co-pilot had 1,100 hours.
Officials who knew Capt Sabharwal, who joined Air India in the late 1990s, described him as 'one of the best pilots of Air India' who 'always followed the rule book and was always sincere towards his work.'
Only a detailed analysis of data from the flight data recorder, when it is found, will answer the questions that remain about Flight 171.