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India Today
6 days ago
- General
- India Today
Was Air India crash mechanical, accidental or…? FAQs answered
The preliminary report of the ongoing investigation into the June 12 crash of the London-bound Air India Flight AI171, soon after take-off from Ahmedabad, has raised various worrying questions, most critically around fuel cut-off to the engines of the Boeing 787 Dreamliner plane and whether this fatal development occurred from a mechanical malfunction or some other cause. INDIA TODAY breaks down the report for answers:Q. What caused both engines of the plane to fail mid-take-off?advertisementA. Three seconds after being airborne, both engine fuel-cut-off switches abruptly moved from 'RUN' to 'CUT-OFF', starving the engines of fuel. Crucially, the pilots denied touching the switches, as per cockpit voice recorder data, and the plane's wreckage showed the switches physically back in 'RUN' some observers, this points strongly to a catastrophic failure of the small latches meant to lock those switches in place—a specific risk flagged in an advisory by the US Federal Aviation Administration (FAA) back in 2018. But to some others, it suggests human error. Q. Why wasn't the risk flagged by the FAA over six years ago fixed on the Air India plane that crashed?A. That critical FAA warning was only an advisory, not a mandatory directive. Air India had the throttle-control module of this plane replaced twice (2019 and 2023), but maintenance logs show that no inspections for the faulty latch mechanism were performed either time. However, the advisory was that in some 737 (not 787) aircraft, it had been found that those switches were installed with faulty locking. The 787 series of aircraft was also mentioned in the FAA advisory because its switches were similar. From images of the wreckage, it would seem that was not the case with Flight AI171. Then again, deeper material analysis is underway to conclude either way.Q. What was so crucial about the FAA advisory?A. To quote a portion of it: 'The Boeing Company (Boeing) received reports from operators of Model 737 airplanes that the fuel-control switches were installed with the locking feature disengaged The fuel control switch has a locking feature to prevent inadvertent operation that could result in unintended switch movement between the fuel supply and fuel cut-off positions. In order to move the switch from one position to the other under the condition where the locking feature is engaged, it is necessary for the pilot to lift the switch up while transitioning the switch the locking feature is disengaged, the switch can be moved between the two positions without lifting the switch during transition, and the switch would be exposed to the potential of inadvertent operation. Inadvertent operation of the switch could result in an unintended consequence, such as an in-flight engine shutdown.'The advisory also says that based on the limited data at that time, it was considered not to turn it into a mandatory check for airline operators. Now, India's Directorate General of Civil Aviation (DGCA) has asked all airlines that have aircraft mentioned in that advisory to carry out an inspection and furnish a report of the findings by July Could the highly experienced pilots have accidentally shut off the fuel supply?A. Both the pilots' credentials and flying experience, as well as common sense strongly suggest otherwise. The two pilots were highly experienced on this specific plane. The cockpit voice recorder data has one of them expressing shock when the plane lost upward thrust and questioning the fuel switch cut-off, while the other denies doing the physical thrust levers were found jammed full forward (take-off position), supporting flight data showing maximum power was commanded until impact. The switches themselves were found in 'RUN' mode after the crash. This combination makes a simple pilot error of bumping the switches incredibly unlikely.Q. Why do modern aircraft, especially the Dreamliner, allow cut off of fuel supply manually when the aircraft is airborne? Isn't there failsafe tech to prevent such a thing?A. Experts cite a variety of reasons. For example, the pilot might need to switch off fuel to one or both engines during landing, based on the dynamic landing environment. The engine does not need full power during taxiing. So, the fuel is cut off then as well. Then there is the scenario of an engine catching fire. In such a case, the pilot might have to cut off fuel supply to that engine to save the aircraft. So the existence of the switches and the behaviour of the aircraft are not in switches are designed in a way that makes the act of turning them a deliberate, 2-3 second job. Moreover, metal guards are installed on either side of the switches to prevent accidental bumping. Some experts have also talked about failure/malfunction of a chip (microprocessor) linked to the GE engine of the Air India plane. But the report does not talk about such a thing.Q. If not a mechanical malfunction or something accidental, what other reason could be attributed to the switches turning off?A. In that case, only one possibility remains—human error. Some global aviation experts seem to be veering towards this theory. Captain Steve Scheibner, a commercial pilot and leading aviation expert with a wide following on YouTube, is of the view that the only way the switches could be off is if someone manually switched them off, and not by accident. He also points out that India's Aircraft Accident Investigation Bureau has onboarded, among others, an 'aviation psychologist'—perhaps to assess the mental health and stress levels of the Flight AI171 pilots during switches are designed in a way that it takes three fingers and a bit of force to turn them. Thus, it's being argued that it's unusual for them to change position because of cockpit vibration or turbulence. The aviation community is also often quoting the infamous Germanwings Flight 9525 crash of 2015.Q. What happened in the Germanwings crash? Are there similarities to the Air India tragedy?A. On March 24, 2015, Germanwings Flight 9525, from Barcelona to Dsseldorf, had crashed into the French Alps, killing all 150 people on board. Investigations revealed that co-pilot Andreas Lubitz intentionally caused the the captain left the cockpit, Lubitz locked him out and then deliberately set the autopilot to descend rapidly into the mountains. Despite efforts by the captain to regain entry and calls from air traffic control, Lubitz maintained control and drove the plane into the ground. It was later discovered that Lubitz had a history of severe depression and had concealed his mental health issues from his is no direct similarity of the Germanwings tragedy to the Flight AI171 crash. However, investigators and experts are drawing parallels in terms of exploring all possibilities, including pilot intent or mental state. The Airline Pilots Association of India has rejected insinuations of suicide or human error and termed such theories as biased. Their argument is also that the pilots are being made to take the fall because they are not around to defend themselves. In any case, a deeper analysis is underway, with a definite outcome of the investigation at least months to India Today Magazine- EndsTrending Reel
Time of India
6 days ago
- Business
- Time of India
'Strict adherence essential...': DGCA's urgent call for Indian Boeing operators after AAIB report
India's civil aviation regulator, DGCA issued urgent directive for Indian operators of Boeing aircraft. DGCA, on July 14, mandated operators to conduct inspections of engine fuel control switch locking mechanisms. Indian Operators of specific Boeing aircraft models are required to conduct the inspection by July 21. This move came days after AAIB released its preliminary report on crash of Air India's AI 171 in Ahmedabad. Directive enforces compliance with FAA's Special Airworthiness Information Bulletin NM-18-33, issued in December 2018. Which warned of potential disengagement of fuel control switch locking feature in operators of Model 737 airplanes. AAIB mentioned in its report that Air India did not comply with FAA's advisory, as it was not a mandate. The fuel control switch design – including locking feature –shared across several Boeing aircraft families. Boeing aircraft families sharing the feature include 737, 747, 757, 767, 777, and 787, the report said. All affected operators to submit their reports to DGCA and the relevant regional officer within the timeframe. Show more Show less
India Gazette
6 days ago
- Automotive
- India Gazette
DGCA asks airlines to conduct fuel switch inspections on Boeing aircraft by July 21
By Shafali Nigam New Delhi [India], July 14 (ANI): India's civil aviation regulator, Directorate General of Civil Aviation (DGCA) on Monday issued an urgent directive mandating Indian operators of specific Boeing aircraft models to conduct inspections of the engine fuel control switch locking mechanisms by July 21. The move comes days after report of preliminary investigation into the crash of Air India flight AI 171 in Ahmedabad in which killed 260 people. The directive enforces compliance with the Federal Aviation Administration's (FAA)'s Special Airworthiness Information Bulletin (SAIB) NM-18-33, issued in December 2018, which warned of the potential disengagement of the fuel control switch locking feature in operators of Model 737 airplanes Boeing aircraft, as mentioned in AI 171 preliminary report. The fuel control switch design, including the locking feature, is similar on various Boeing airplane models including part number 4TL837-3D which is fitted in B787-8 aircraft VT-ANB, the preliminary report added. The fuel control switch design--including the locking feature--is shared across several Boeing aircraft families, including the 737, 747, 757, 767, 777, and 787, the report said. AAIB's findings reignited concern over why many airlines had delayed or skipped the inspections, even after the issue had been flagged internationally. The order mandates all affected operators to complete inspections in line with the FAA's SAIB NM-18-33 and submit their inspection plans and final compliance reports to both the DGCA and relevant regional offices. The DGCA noted in its directive that several international and domestic operators had voluntarily begun compliance following the FAA bulletin. The order explicitly refers to India's Civil Aviation Requirement (CAR) M-M.A. 301, which obligates operators to comply with safety directives from aircraft manufacturers or regulators of the aircraft's state of design, in this case, the U.S. FAA. 'Strict adherence is essential for continued airworthiness and safety of operations,' the DGCA stated. India's Aircraft Accident Investigation Bureau (AAIB) released the preliminary report into the tragic crash of Air India flight AI171, a Boeing 787-8 aircraft, which crashed shortly after takeoff from Ahmedabad's Sardar Vallabhbhai Patel International Airport on June 12. The crash killed 260 people, including 229 passengers, 12 crew members, and 19 people on the ground. Flight data recovered from the aircraft's Enhanced Airborne Flight Recorder (EAFR) revealed that the fuel cutoff switches for both engines were inadvertently moved from RUN to CUTOFF, one after another within a 1-second interval, at an altitude just moments after liftoff. One pilot was heard asking the other, 'Why did you cut off?' to which the response was, 'I did not.' This uncommanded shutdown triggered the deployment of the Ram Air Turbine (RAT), and the aircraft began losing altitude almost immediately, unable to sustain powered flight. According to the AAIB, the pilots re-engaged the fuel switches in an attempt to relight both engines. Engine 1 showed signs of recovering thrust, but Engine 2 failed to stabilise. The aircraft, which had briefly reached a speed of 180 knots, was already descending and failed to regain altitude. The final distress call -- a 'MAYDAY' -- was transmitted at 08:09 UTC, just seconds before the aircraft crashed into residential buildings outside the airport perimeter. (ANI)
NDTV
12-07-2025
- Automotive
- NDTV
"Was Advisory, Not Mandatory": Air India On US Report On Fuel Control Switch
Fuel control switches to the engines of an Air India flight that crashed shortly after takeoff, killing 260 people, were moved from the "run" to the "cutoff" position moments before impact, a preliminary investigation report said early Saturday. The report, issued by India's Aircraft Accident Investigation Bureau (AAIB), said that the US Federal Aviation Administration (FAA) had issued an information bulletin in 2018 about "the potential disengagement of the fuel control switch locking feature". Though the concern was not considered an "unsafe condition" that would warrant a more serious directive, Air India told investigators it did not carry out suggested inspections as they were "advisory and not mandatory". Fuel control switches regulate the flow of fuel into an aircraft's engines. Air India Boeing 787-8 Dreamliner was headed from Ahmedabad to London when it crashed, killing all but one of the 242 people on board as well as 19 people on the ground. "The FAA issued Special Airworthiness Information Bulletin (SAIB) No. NM-18-33 on December 17, 2018, regarding the potential disengagement of the fuel control switch locking feature," said the preliminary report. Air India was compliant with all airworthiness directives and alert service bulletins on the aircraft, the report said. "This SAIB was issued based on reports from operators of Model 737 airplanes that the fuel control switches were installed with the locking feature disengaged. The airworthiness concern was not considered an unsafe condition that would warrant airworthiness directive (AD) by the FAA," it said. "As per the information from Air India, the suggested inspections were not carried out as the SAIB was advisory and not mandatory. The scrutiny of maintenance records revealed that the throttle control module was replaced on VT-ANB in 2019 and 2023," it added. The fuel switch has two positions -- 'RUN' and 'CUT OFF' -- and are used to start or shut down engines. In its 15-page report, the investigation bureau said that once the aircraft achieved its top recorded speed, "the Engine 1 and Engine 2 fuel cutoff switches transitioned from RUN to CUTOFF position one after another with a time gap of 01 sec". The switches then returned to the "RUN" position and the engines appeared to be gathering power, but "one of the pilots transmitted 'MAYDAY MAYDAY MAYDAY'", the report said. The report did not offer any conclusions or apportion blame for the June 12 disaster, but indicated that one pilot asked the other why he cut off fuel, and the second pilot responded that he had not. Boeing said in a statement it will "continue to support the investigation and our customer", adding "our thoughts remain" with those affected by the disaster. Air India said it was "working closely with stakeholders, including regulators." "We continue to fully cooperate with the AAIB and other authorities as their investigation progresses," it said in a statement on X.
News18
12-07-2025
- Automotive
- News18
FAA Warned In 2018 Of Boeing Engine Shutdown Risk But Air India Ignored Fuel Switch Advisory
Last Updated: To move the switch from one position to the other where the locking feature is engaged, it is necessary for the pilot to lift the switch up while transitioning the switch position Did the fuel control switch in the ill-fated Air India 171 Boeing aircraft malfunction because it was disengaged and not locked? The preliminary inquiry report into the incident points to an FAA warning in 2018 that said inadvertent operation of the switch could result in an unintended consequence, such as an in-flight engine shutdown. But the report has stopped short of blaming this as the cause for the crash. CNN-News18 has accessed the 2018 warning by Federal Aviation Administration (FAA) that Boeing received reports from operators of Model 737 airplanes that the fuel control switches were installed with the locking feature disengaged. The fuel control switches (or engine start switches) are installed on the control stand in the flight deck and used by the pilot to supply or cut off fuel to the engines. The fuel control switch has a locking feature to prevent inadvertent operation that could result in unintended switch movement between the fuel supply and fuel cut-off positions. To move the switch from one position to the other under the condition where the locking feature is engaged, it is necessary for the pilot to lift the switch up while transitioning the switch position. 'If the locking feature is disengaged, the switch can be moved between the two positions without lifting the switch during transition, and the switch would be exposed to the potential of inadvertent operation. Inadvertent operation of the switch could result in an unintended consequence, such as an in-flight engine shutdown," the FAA warning said. 'While the airplane is on the ground, check whether the fuel control switch can be moved between the two positions without lifting up the switch. If the switch can be moved without lifting it up, the locking feature has been disengaged and the switch should be replaced at the earliest opportunity," the FAA said. For Boeing Model 737-700, -700C, -800, and -900ER series airplanes and Boeing Model 737-8 and -9 airplanes delivered with a fuel control switch having P/N 766AT613-3D, it was advised that the fuel control switch be replaced with a switch having P/N 766AT614-3D, which includes an improved locking feature. Was this Done? The AAIB report says that the fuel control switch design, including the locking feature, is similar on various Boeing airplane models including part number 4TL837-3D which is fitted in B787-8 aircraft VT-ANB that crashed in Ahmedabad. 'As per the information from Air India, the suggested inspections were not carried out as the FAA directive was advisory and not mandatory. The scrutiny of maintenance records revealed that the throttle control module was replaced on VT-ANB in 2019 and 2023. However, the reason for the replacement was not linked to the fuel control switch. There has been no defect reported pertaining to the fuel control switch since 2023 on VT-ANB," the AAIB report says. What Happened on AI-171 After the AI-171 aircraft achieved the maximum recorded airspeed of 180 Knots, immediately thereafter, the Engine 1 and Engine 2 fuel cut-off switches transitioned from RUN to CUTOFF position one after another with a time gap of 01 sec, says the AAIB report. The Engine N1 and N2 began to decrease from their take-off values as the fuel supply to the engines was cut off. '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," the report says. The pilots then tried to restart the engines—but it was too late. view comments First Published: Disclaimer: Comments reflect users' views, not News18's. Please keep discussions respectful and constructive. Abusive, defamatory, or illegal comments will be removed. News18 may disable any comment at its discretion. By posting, you agree to our Terms of Use and Privacy Policy.
