The furious dispute over what caused Air India flight 171 to crash
It was a hot and dry afternoon on 12 June last year, when Air India Flight 171 departed from Sardar Vallabhbhai Patel Airport in Ahmedabad, located in the western Indian state of Gujarat. Onboard were 230 passengers, including 169 Indian nationals and 53 Britons, accompanied by 10 cabin crew members for the nine-and-a-half-hour journey to London.
The flight deck was manned by Captain Sumeet Sabharwal, a pilot with decades of experience, and his younger colleague, first officer Clive Kunder. Just 32 seconds after takeoff, the aircraft crashed, resulting in the deaths of all but one person on board. Additionally, 19 individuals on the ground lost their lives.
CCTV footage from the airport and a video circulated on social media depict the aircraft taking off in what appears to be a normal manner. However, instead of gaining altitude, the plane seems to hover momentarily before descending gently. It then disappears behind buildings and trees, followed shortly by a large cloud of flame and black smoke, revealing the scale of the tragedy. The footage, however, does not clarify the cause of the crash.
The crash claimed the lives of all but one onboard, Vishwash Kumar Ramesh.
The responsibility for determining the cause of the crash lies with India's Aircraft Accident Investigation Bureau (AAIB), which operates under the Ministry of Civil Aviation. International law, as outlined in Annex 13 of the Convention on International Civil Aviation, mandates that the country where an accident occurs leads the official investigation.
Other parties, such as the countries where the aircraft or its engines were manufactured, may participate as "accredited representatives." In the case of AI171, this includes the US National Transportation Safety Board (NTSB), which dispatched a delegation comprising technical experts from Boeing, the aircraft manufacturer, GE Aerospace, the engine maker, and the Federal Aviation Administration (FAA), the US aviation regulator.
Annex 13 emphasizes that "the sole objective of the investigation of an accident or incident shall be the prevention of accidents or incidents. It is not the purpose of this activity to apportion blame or liability."
Despite this, the stakes are high. For Boeing, already affected by previous safety controversies, the integrity of the 787 Dreamliner—a model with a previously impeccable safety record—is at risk. Air India, a loss-making airline under the Tata Group, faces potential brand damage. Families of the victims seek clarity on the circumstances surrounding the tragedy.
The final conclusions of the investigation have yet to be released, though further details may emerge soon. The inquiry has already sparked intense debate, raising broader concerns about the conduct of major air accident investigations. Questions persist about whether national authorities can be trusted to carry out impartial investigations free from political or corporate influence.
The inquiry backlash
Ideally, the investigation should be impartial and focused on enhancing passenger safety. However, the information disclosed so far has provoked significant backlash from safety advocates, pilot organizations, and legal representatives of the victims' families.
A major point of contention is the preliminary report issued by the AAIB one month after the crash. The 15-page document refrained from drawing conclusions about the crash's cause or issuing recommendations.
Nevertheless, two brief paragraphs ignited controversy.
The report noted that the aircraft's flight data recorder indicated that both fuel cutoff switches—typically used during engine start and shutdown—moved from the "run" to the "cutoff" position seconds after takeoff. This action would have cut off fuel to the engines, causing rapid loss of thrust.
It further stated:
"In the cockpit voice recording, one of the pilots is heard asking the other why did he cutoff. The other pilot responded that he did not do so."This statement, presented without a transcript or identification of the speakers, fueled speculation about pilot actions. Newsweek highlighted the "troubling possibility: that a seasoned captain may have deliberately doomed his jet – and nearly 250 lives." Former NTSB chairman Robert Sumwalt told CBS News that the report indicated "this was not a problem with the airplane or the engines. Instead…somebody in the cockpit shut the fuel off to those engines."
Subsequently, The Wall Street Journal cited sources familiar with the matter, claiming that pilot dialogue recordings suggested Captain Sumeet Sabharwal had flipped the fuel switches.
It is important to emphasize that this was a preliminary report. Within days, the AAIB condemned "selective and unverified reporting" in the international media as "irresponsible," urging the public and press to "refrain from spreading premature narratives that risk undermining the integrity of the investigative process."
By then, however, considerable damage had arguably occurred.
"When a pilot is alive he can defend himself," said Capt. CS Randhawa, president of the Federation of Indian Pilots (FIP). "When the pilot is dead, all the agencies can collude – and they put the blame on the pilot, to save the manufacturer. And this is seen the world over. It's not the first time."
The FIP, representing approximately 6,000 pilots, condemned the preliminary report as "irrevocably compromised." Alongside Captain Sabharwal's 91-year-old father, Pushkar Raj Sabharwal, they petitioned India's Supreme Court, requesting a judicial investigation into the crash.
Safety campaigners in India and the US have strongly opposed the pilot suicide theory.
Former UK air accident investigator Tim Atkinson acknowledged the common tendency to blame deceased pilots for accidents.
"It's incredibly, incredibly convenient for all concerned," he said. "You know, the regulator's off the hook, the operator's off the hook, the manufacturer's off the hook. And that's why you have to push back against it so hard."
Nonetheless, Atkinson personally believes no other credible explanation exists in this case, a view shared by many aviation professionals.
"I am in absolutely no doubt this is a homicide-suicide. And if you set out to investigate one of those, and try to show it is an aviation accident, you'll fail – because it isn't," he explained.
Conversely, safety advocates in India and the US, along with the FIP, have contested the pilot suicide theory. They cite reports of prior aircraft faults and inconsistencies in the preliminary report's timelines as evidence supporting the possibility of a severe electrical failure causing the crash.
The aircraft, registered VT-ANB, was delivered to Air India in 2014. According to the Foundation for Aviation Safety, a US organization led by former Boeing manager turned whistleblower Ed Pierson, the plane experienced multiple serious electrical issues during its service life. Air India denies these claims.
Documents reviewed by the BBC reveal an incident of "burning" in one of the aircraft's main power panels in 2022. Air India stated that repairs were "carried out in accordance with Boeing-approved maintenance procedures" and that "the aircraft was returned to service only after applicable airworthiness requirements had been satisfied."
The preliminary report also notes that the aircraft was authorized to fly despite a known fault in its "core network," a system connecting the aircraft's computers and electronics, often described as the plane's "central nervous system." Boeing has deferred all inquiries regarding the incident to the Indian AAIB.
Competing theories
One prominent theory proposed by campaigners suggests that a major electrical failure caused the aircraft's primary flight computers to reboot seconds after takeoff. This reboot allegedly led the systems to mistakenly believe the aircraft was on the ground, despite being airborne. Consequently, a safety system detected what it interpreted as dangerously high engine thrust, assumed a malfunction, and commanded fuel supply cutoff.
Under this scenario, the cockpit fuel switches were not physically manipulated; rather, the flight data recorder may have recorded an electronic command to cut fuel, not the physical switch movement.
Investigative journalist Rachel Chitra, who has published detailed technical articles in India, supports this theory. She highlights several inconsistencies in the preliminary report, including descriptions of engine relight attempts after fuel restoration.
The report states: "Engine 1's core deceleration stopped, reversed and started to progress to recovery. Engine 2 was able to relight but could not arrest core speed deceleration…" However, Chitra's research, supported by engineering documents, argues that such relight would have been physically impossible given the aircraft's speed and available power sources.
Meanwhile, lawyers representing victims' families have scrutinized the timing of the deployment of an emergency power system known as the Ram Air Turbine (RAT). The RAT is a small propeller that rotates in the airstream to supply electricity and hydraulic pressure when other systems fail. CCTV footage shows the RAT deployed immediately after takeoff.
The preliminary report indicates the RAT provided hydraulic power within five seconds of the fuel switches being cut. However, simulator tests shared with the BBC suggest it would require 14-18 seconds to deploy, implying the RAT may have activated earlier, possibly while the aircraft was still on the ground and before fuel cutoff.
Mike Andrews, an attorney with the Beasley Allen law firm representing families of 135 victims, stated that these findings raise significant questions challenging the pilot suicide narrative.
"The RAT deployment is a symptom of something else going on," he explained. "In order for it to be out, something has happened…if it is out prior to the fuel switch allegation, our question still is: why? It is a symptom of something that has gone wrong."
Safety consultant and author Eckhard Jann considers such controversy inevitable in cases like this.
"We have gotten used to safe airline travels," he said, "and as the reason for the B787 crash in Ahmedabad is unknown, it rattles the world."
Former investigator Tim Atkinson regards the complex multiple electrical failure theory as unrealistic, citing the plane's system architecture as a limiting factor.
For Atkinson, the controversy surrounding AI171 reflects the difficulty in discussing homicide and suicide in aviation accidents.
Under Annex 13, investigators are expected to publish a final report within 12 months if possible. If not, an interim report must be issued on the accident's anniversary. Therefore, India's AAIB must release an update by Friday, 12 June.
However, widespread skepticism exists regarding the report's conclusiveness. In May, India's civil aviation minister stated the investigation was in its "last stage" and that the final report would "mostly…come after a month."
Controversy and cynicism
Regardless of the forthcoming report, it is unlikely to quell the controversy and skepticism surrounding the AI171 investigation.
Much of this stems from perceptions that involved companies are shielded from accountability.
Boeing, in particular, cannot afford doubts about the 787's safety. Despite early issues, including a major battery fire at Boston airport in 2013, the 787 had maintained an impressive safety record until AI171, which marked the first loss of a 787 due to an accident. However, production has faced challenges, including defects and manufacturing problems, with whistleblowers highlighting unsafe practices on the production line. Boeing has consistently denied allowing unsafe aircraft into service.
The manufacturer's corporate culture has faced criticism following issues with the 737 Max, which was involved in two fatal crashes, prompting regulators to mandate a comprehensive safety and quality improvement plan.
Air India has endured years of financial losses. Formerly government-owned until 2022, it was acquired by the Tata Group, which aimed to revitalize the airline. Despite this, Air India continues to face difficulties in a challenging industry environment and cannot afford further brand damage.
This is not the first time the current system for investigating major air accidents has been criticized. The AI171 case has underscored ongoing concerns about the integrity of high-profile, politically sensitive inquiries.
The Foundation for Aviation Safety, a non-profit organization, warns that entrusting investigations to the country where the accident occurred can entangle the process in local bureaucracy or political pressures. Moreover, manufacturers' technical experts, while assisting investigators, may face pressure to deflect corporate responsibility.
"Diagnosing an extremely complex airplane with an outdated playbook is impossible," said Ed Pierson, the Foundation's executive director.
Eckhard Jann notes that the current system is largely based on principles established in 1944. In today's globalized context, he believes "investigating authorities are having more and more difficulty fulfilling their duties: to investigate independently and make solid recommendations in order to improve aviation safety."
The International Civil Aviation Organisation (ICAO), the UN agency overseeing international air travel, recognizes the vulnerability of investigations to conflicts of interest. In March, it announced changes to Annex 13, providing guidance for states to enhance credibility and transparency, including delegating investigations to third parties if necessary. These measures will take effect in late 2028.
However, Jann considers these changes insufficient, describing them as "just a sticking plaster." He advocates for "a global investigation authority with enough power to demand changes based on their recommendations."
Others question the value of such investigations given their cost and complexity. Former investigator Tim Atkinson remarked:
"This cycle of an accident happens, you investigate it impartially, make recommendations, prevent future occurrences… it doesn't really happen any more. The things that prevent people dying these days are nothing to do with that. They're to do with better technology."
He advocates for greater transparency and earlier dissemination of information during investigations.
"I've always believed that," he said. "And I've never seen negative consequences of it."
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When an Air India plane heading to London crashed in a residential area of the Indian city of Ahmedabad, just seconds after takeoff, it killed all but one onboard. We hear from eyewitnesses, aviation experts, and the families of those who died.
