The preliminary investigation report on last month's Air India crash found no mechanical or maintenance issue with the aircraft, the company's chief executive said.
In an internal memo, Campbell Wilson said the probe into the Boeing Dreamliner crash in Ahmedabad, which killed 260 people, was "far from over". He added the pilots had “passed” all pre-flight checks amid allegations that the disaster was caused by human error.
The report found "no mechanical or maintenance issues with the aircraft or engines and that all mandatory maintenance tasks had been completed," Mr Wilson said.
"There was no issue with the quality of fuel and no abnormality with the take-off roll.”
The report released by India's Aircraft Accident Investigation Bureau a month after the 12 June crash found that three seconds after taking off, the plane’s fuel switches almost simultaneously flipped from run to cutoff, starving the engines.
The London-bound Dreamliner immediately began to lose thrust and sink.
According to the report, one pilot could be heard on the cockpit voice recorder asking the other why he had cut off the fuel. "The other pilot responded that he did not do so," it said.
It did not identify which remarks were made by the flight's captain and which by the first officer, nor which pilot transmitted "Mayday, Mayday, Mayday" just before the crash.
At the crash site, both fuel switches were found in the “run” position and the report noted that there had been indications of the engines relighting before the low-altitude crash.
Rejecting allegations of pilot error causing the crash, the Air India chief said that they both had "passed their pre-flight breathalyser and there were no observations pertaining to their medical status".
The aircraft was piloted by Captain Sumeet Sabharwal and assisted by First Officer Clive Kundar. Both were experienced jet pilots with nearly 19,000 flying hours between them, including more than 9,000 on Boeing 787.
The Airline Pilots' Association of India (ALPA-India), representing Indian pilots at the International Federation of Air Line Pilots Associations, Montreal, also rejected the presumption of pilot error and called for a "fair, fact-based inquiry".
"The pilots’ body must now be made part of the probe, at least as observers," ALPA India president Sam Thomas told Reuters.
American aviation safety expert John Cox said a pilot would not be able to accidentally move the fuel switches feeding the engines. "You can't bump them and they move," he said.
ALPA India, in a letter posted on X, said the preliminary investigation report referred to a 2018 FAA advisory "concerning the fuel control switch gates, which indicates a potential equipment malfunction".
The Indian Commercial Pilots’ Association said the ill-fated flight’s pilots "should not be vilified based on conjecture", adding that the crew "acted in line with their training and responsibilities under challenging conditions". "To casually suggest pilot suicide without verified evidence is a gross violation of ethical reporting and a disservice to the dignity of the profession," it said in a statement.
"Let us be unequivocally clear,” it added, “there is absolutely no basis for such a claim at this stage and invoking such a serious allegation based on incomplete or preliminary information is not only irresponsible – it’s deeply insensitive to the individuals and families involved."
Relatives of the crash victims criticised the preliminary report as a "cover up" as they hoped for more answers from the investigators.
A cousin of sisters Dhir and Heer Baxi, who were flying home to London when they died in the crash, said they were not satisfied with the report, The Guardian reported.
Ishan Baxi said they were "still hoping for a more transparent and honest investigation that doesn’t shy away from addressing possible mechanical flaws or lapses in protocol to avoid future potential accidents”.
“I just hope the final report brings full clarity on what exactly failed and who’s accountable. It shouldn’t hide behind vague terms. More than anything, it should push for real changes so this never happens again," the Ahmedabad resident said.
Tushar Joge, whose two relatives were on the ill-fated aircraft, alleged that the preliminary report was a "cover up" to save Air India and Boeing. "We were pre-empting that they would start blaming the pilots," Mr Joge was quoted as saying by The Times of India.
In the wake of the preliminary findings, Boeing privately issued a notification stating that the fuel switch locks on Boeing planes were safe, Reuters reported.
The US Federal Aviation Administration separately said that "although the fuel control switch design, including the locking feature, is similar on various Boeing airplane models, the FAA does not consider this issue to be an unsafe condition that would warrant an Airworthiness Directive on any Boeing airplane models, including the Model 787”.
Meanwhile, South Korea is preparing to order all airlines in the country that operate Boeing jets to examine fuel switches in the focus of an investigation of the Air India crash.
Fuel switch locks have come under scrutiny after a mention of a 2018 advisory from the US Federal Aviation Administration (FAA) in a preliminary report into last month's crash of Air India's Boeing 787-8 jet.
A spokesperson for the South Korean transport ministry said the checks were in line with a 2018 advisory from the FAA, but did not give a timeline for inspections.
Boeing referred Reuters' questions to the FAA, which was not immediately available to comment outside regular hours.
The 2018 FAA advisory recommended, but did not mandate, operators of several Boeing models, including the 787, to inspect the locking feature of the fuel cutoff switches to ensure they could not be moved accidentally.
On Sunday, citing a document and sources, Reuters reported that the planemaker and the FAA had privately issued notifications to airlines and regulators that the fuel switch locks on Boeing planes were safe and checks were not required.
The Air India preliminary report said the airline had not carried out the FAA's suggested inspections as the FAA's 2018 advisory was not a mandate.
But it also said maintenance records showed that the throttle control module, which includes the fuel switches, was replaced in 2019 and 2023 on the plane involved in the crash.
