Black box data tells all about deadly flight Air India 171: Full sequence of events that ended in a tragic crash
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Flight AI423 had a Pilot Defect Report (PDR) entry for a status message: 'STAB POS XDCR' in the tech log.
Troubleshooting was carried out, and the aircraft was released for flight.
The pilots had adequate rest, underwent pre-flight breath analyser tests, and were found fit to operate the flight.
Fuel on board was 54,200 kg, and the takeoff weight was 213,401 kg, which was within the maximum allowed limit of 218,183 kg.
No dangerous goods were onboard the aircraft.
The aircraft began its takeoff roll at 08:07:37.
The air/ground sensors transitioned to 'air mode,' consistent with liftoff at 08:08:39.
The aircraft achieved a maximum recorded airspeed of 180 knots IAS at approximately 08:08:42.
Immediately after, Engine 1 and Engine 2 fuel cutoff switches were moved from RUN to CUTOFF positions, one after another, with a one-second gap.
As fuel supply to the engines was cut off, both N1 and N2 values began to decrease from their takeoff values.
In the cockpit voice recording, one pilot is heard asking the other, 'Why did you cut off?'
The other pilot responded that he did not.
CCTV footage from the airport showed the Ram Air Turbine (RAT) deploying during the initial climb, immediately after liftoff.
No significant bird activity was observed near the flight path.
The aircraft began to lose altitude before crossing the airport perimeter wall.
According to EAFR data, both engines' N2 values dropped below the minimum idle speed, and the RAT hydraulic pump began supplying power at around 08:08:47.
At approximately 08:08:52, Engine 1's fuel cutoff switch transitioned back from CUTOFF to RUN.
At 08:08:56, Engine 2's fuel cutoff switch also transitioned from CUTOFF to RUN.
When fuel control switches are moved from CUTOFF to RUN during flight, the Full Authority Dual Engine Control (FADEC) system automatically initiates a relight and thrust recovery sequence, including ignition and fuel reintroduction.
Exhaust Gas Temperature (EGT) began rising for both engines, indicating relight.
Engine 1's core deceleration stopped, reversed, and began recovering.
Engine 2 managed to relight but could not stop the core speed deceleration. It kept reintroducing fuel in attempts to increase acceleration and achieve recovery.
The EAFR recording stopped at 08:09:11.
At around 08:09:05 UTC, one of the pilots transmitted: 'MAYDAY, MAYDAY, MAYDAY.'
Air Traffic Control (ATCO) asked for the call sign but received no response.
ATCO then observed the aircraft crash outside the airport boundary and immediately activated the emergency response.
On June 12, tragedy struck as Air India Flight 171 crashed just moments after takeoff, despite no signs of mechanical issues or external threats like bird strikes. In a shocking chain of events, both engines shut down mid-air, cockpit confusion unfolded, and a desperate Mayday call went unanswered.A detailed sequence reconstructed from technical logs, cockpit voice recordings, and CCTV footage now reveals the terrifying final moments of the flight, offering a chilling look into what caused the deadly crash.Below is the minute-by-minute breakdown of what exactly happened from takeoff to impact.Here is the sequence of events leading to the deadly crash on June 12:
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NDTV
15 minutes ago
- NDTV
"Not Satisfied": Air India Plane Crash Victim's Father Demands Strict Action
Mehsana (Gujarat): The father of Sanket Goswami, a 19-year-old student who died in last month's Air India AI171 crash, stated that he was "not satisfied" with the preliminary investigation report released by the Aircraft Accident Investigation Bureau (AAIB), and requested the government to conduct a "thorough investigation". He also urged the government to take strict action against those responsible for the incident. Sanket's father, Atul Goswami, told ANI, "My son was 19 years old... My family is living under such difficult circumstances. We used to rely on my son a lot. He was going to London for three years to get his degree. Our whole family relied on him... We are not satisfied with the report. We request the government to conduct a thorough investigation and strict action be taken against the responsible parties..." The AI171 crash took place on June 12, when the London-bound Air India Boeing 787-8 aircraft crashed shortly after takeoff from Ahmedabad's Sardar Vallabhbhai Patel International Airport. The aircraft hit a hostel building at BJ Medical College, killing 241 of the 242 people on board. Among the victims was former Gujarat Chief Minister Vijay Rupani. It is one of the worst air disasters in India in recent years. On Friday, the AAIB released its preliminary report into the crash. It described a critical situation that developed just 90 seconds after takeoff, when both engines shut down unexpectedly during the climb. This led to a loss of thrust and a rapid drop in altitude. Flight data from the aircraft's Enhanced Airborne Flight Recorder (EAFR) showed that the fuel cutoff switches for both engines were accidentally moved from RUN to CUTOFF within one second of each other, shortly after takeoff. One pilot was heard asking the other, "Why did you cut off?" to which the response came, "I did not." The sudden shutdown caused the Ram Air Turbine (RAT) to deploy, but the aircraft began losing height immediately and could not stay in the air without engine power. According to the AAIB, the pilots tried to relight both engines by switching the fuel systems back on. While Engine 1 started to recover, Engine 2 did not stabilise. Even though the aircraft briefly reached 180 knots, it continued to descend. The final distress call, a "MAYDAY", was sent at 08:09 UTC, seconds before the crash.
The Print
18 minutes ago
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Air India crash should push India to create independent board for transport safety oversight
I was on a 'deadheading' flight to Surat (VASU) just as the first newsbreaks of the crash erupted on social media. Fortunately, our crew were on 'airplane mode' and blissfully unaware about the horrific crash till we landed at Surat about an hour later. The immediate aftermath of any major air accident is often dominated by shock, confusion, devastation, (mass) casualties and, in a country like India with 1.4 bn population, a flood of curious onlookers and volunteers trying to help or rescue. Such first aid efforts must soon make way for professional rescue and fire fighting efforts. This should be followed by securing of the accident site for initial investigation. AAIB spells it out clearly on their website: ' the primary aim for the initial investigation is to gather and preserve perishable evidence, for subsequent analysis, that may be lost over time and not available to the Investigators after a delay '. This is the first fatal accident and hull loss of Boeing's Dreamliner which, as per Boeing Company website 'has carried more than one billion passengers, faster than any other widebody jet in aviation history' in over 5 million flights. Air India's ill-fated VT-ANB was manufactured in 2013 and had flown 41868 hours. On June 12, 2025, VT-ANB, a Boeing 787-8 Dreamliner operated by Air India as AI-171 from Ahmedabad to London Gatwick, crashed soon after takeoff from Sardar Vallabhbhai Patel International Airport's (VAAH) Runway 23 at about 0809 UTC (1339 IST). Amateur videos, CCTV grabs and eyewitness accounts indicated a distinct loss of thrust immediately after liftoff. The aircraft went into the ground wings level, nose up, landing gear down and impacted BJ Medical College Hostel, about 0.9 NM from departure end of RW 23. 241 of the 242 onboard (12 crew + 229 pax) and 19 on the ground perished in the crash. One passenger, Mr Vishwas Kumar Ramesh, miraculously survived with minor injuries and walked away from the burning wreckage (report classifies his injuries as 'serious'). Disaster tourism impacts investigation A team from AAIB headed by the DG himself reached Ahmedabad on the same day. It is likely that dusk/night would have set in by that time, leaving the quick reaction team from AAIB struggling to retrieve evidence from a site literally and metaphorically draped in darkness. This is about the time in India most VVIPs finalise their plan to visit accident sites. As expected, PM Modi and his entourage arrived at the crash site the very next day (Jun 13). Amidst a mountain of debris, flaming avcat, strewn body parts and pieces of wreckage screaming 'evidence', I leave it to the readers to estimate what impact such kind of catastrophe porn will have on an investigative process in its most important and fragile phase. They were literally walking all over the evidence. Such visits by political leaders are party-agnostic and maybe meant to assuage shocked citizens but it takes a bulldozer to the investigative process. Careful collection & preservation of all evidence is key to any investigation. Anyone not directly involved with rescue or investigation, incl VIPs, should keep away from the crash site. It does not happen in any part of the developed world. It should be proscribed by law in my view. AAIB India In India, the authority designated by the State as responsible for aircraft accident and incident investigations within the framework of ICAO Annex 13 is the Aircraft Accident Investigation Bureau (AAIB) headed by a Director General (DG). The AAIB works as an attached office to Government of India, Ministry of Civil Aviation. The DG, AAIB reports to Secretary, Ministry of Civil Aviation. AAIB India is relatively new, so is the current DG, an IAF officer on deputation to the AAIB who took over on 18 Dec 2023. The investigation is conducted under the framework defined in Aircraft (Investigation of Accidents and Incidents) Rules, 2017. Lack of timely updates After such an accident with mass casualties, victims' families, air travelers, and all stakeholders deserve timely updates on how the accident investigation is proceeding. Nobody expects a running commentary but in the absence of timely factual data from authorities, there is a serious risk of conspiracy theories and speculation running riot. That is exactly what happened after AI-171. An information blackout followed till release of the first update on 26th June, clear two weeks after the crash. By this time, keyboard warriors and air crash influencers flooded the space with speculation, notching up millions of views per video and driving the 'narrative war'. The sketchy information shared by Indian media (sample below) only added to the embarrasment. For instance, in which country does air accident investigation wait for the prime minister's suggestion on due process to be followed? There were absolutely no briefs, no updates worth the loss. The usual drama & violation of crash site by ministers for photo ops, wreckage snagging in trees during transportation etc. inspired little confidence. Meanwhile a news scoop by a foreign media The Air Current couple of days prior to release of the preliminary report by AAIB at about 0200 IST on 12 Jun 25 exposed the leaky system we have. Here is what I can glean from the preliminary report Technical Scrutiny of the aircraft journey log book detailed in the prelim report does not indicate any major issues. It is not unusual for aircraft to fly with Minimum Equipment List (MEL) invoked. It includes equipment 'which may be inoperative and yet maintain an acceptable level of safety by appropriate conditions and limitations'. The approved company MEL is drawn up from the manufacturer's Master MEL and duly approved by the regulator (in this case DGCA). The category of MEL indicates the repair interval of the equipment and permissible window for operation with MEL invoked. VT-ANB was flying with four Cat C and one Cat A MEL invoked. None of them appear to have a direct bearing on the accident. All applicable airworthiness directives (AD) and Alert Service Bulletins (ASB) were complied with on the aircraft and its systems. Fuel samples taken from the bowsers and tanks used to refuel the aircraft were tested and found satisfactory. The aircraft was fully configured for takeoff, well within performance limits for that day, and used full usable length of the runway. This puts paid to needless speculation around fuel contamination, early flap retraction etc. that flew thick and fast in the wake of the accident. Pilots Both pilots were qualified and in current flying practice. The total cockpit experience was a solid 19000h (9700h on type). The pilot-in-command was highly experienced with multiple endorsements including B787, B777 and A310. He was the Pilot Monitoring (PM) while the copilot with about 3400h (1128h on type) was the Pilot Flying (PF). Both pilots had adequate rest period before their duty roster and cleared preflight breathalyser tests. Postmortem examination findings of the crew are being analysed 'to corroborate aeromedical findings with the engineering appreciation'. This is usual practice in any accident investigation. EAFR VT-ANB was equipped with dual Enhanced Airborne Flight Recorders (EAFR) in two distinct locations, forward and aft. The prelim report analyses are likely based on data retrieved from the forward EAFR, which owing to its independent power source continues to record digital flight data and cockpit voice even in the event of a total power loss. This will be important in reconstructing the events preceding and immediately following the dual engine rollback due to its uninterrupted recording capability. The aft EAFR suffered extensive damage and could not be downloaded, as per the report. Also read: Uttarakhand crash shows how cheap a pilgrim's life is. Helicopter rides cheaper than pony The final moments The aircraft started up, taxied out, backtracked and lined up on Runway 23 as per normal procedure. The takeoff roll commenced at 08:07:37 UTC and liftoff was achieved roughly a minute later at 08:08:39 UTC. The report has time-stamped data of critical speeds achieved during the takeoff roll (V1, Vr, V2). There seems to be nothing unusual while the aircraft was still in 'ground' mode. The accident sequence unravelled about 3 seconds after liftoff, immediately after the aircraft's air/ground sensors transitioned to 'air' mode. The highlighted para from AAIB report below is likely to be the focal point of further investigation: The aircraft achieved the maximum recorded airspeed of 180 knots IAS at about 08:08:42 UTC and immediately thereafter, 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 Engine N1 and N2 began to decrease from their take-off values as the fuel supply to the engines was cut off. From that point onwards, AI-171 was doomed. The first cockpit exchange following the uncommanded engine roll back is also very unusual given that both pilots would be scanning areas in and out of the cockpit that doesn't include the thrust lever quadrant. Even if the fuel switches move from RUN to CUTOFF, it would have set off a series of failure captions, audio voice warnings and loss of thrust that demand immediate action rather than the query recorded in the report below: 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. Thrust lever and fuel switch movement till impact indicate a last-ditch effort to relight the engine, which includes recycling the fuel switches from CUTOFF to RUN. By then it was too late. No wide-body aircraft can safely recover from a dual engine failure at that low height. Impact, death and destruction were imminent, but there was no sign of any sharp change in attitude or a wing drop. One of the pilots transmitted a MAYDAY call 5 seconds before impact. The crew likely flew the aircraft all the way till impact. There is no sign of any kind of startle response or pilot incapacitation. How/why did the fuel control switches roll back? There is science and human factors behind the engineering design of every single switch in a cockpit. A host of safeguards such as location, shape, tactile feel, guard, detent, etc. are used to reduce or preclude inadvertent or incorrect operation of any safety critical switch or lever. It is inconceivable that ANY sane pilot would inadvertently or intentionally move a critical engine control to CUTOFF at such a point during takeoff. The trans-cockpit authority gradient was hardly shallow with a senior 15000h PIC and a 3400h first officer. Since the younger, less experienced copilot was the PF, the query 'why did he (you) cutoff' likely came from the PM. The fuel switches are nowhere near the yoke; there is no reason for the PF to reach down to the two fuel switches at that critical point in takeoff. His reply that 'he (i) did not do so' also leaves a critical question unanswered — was the 'transition'of fuel switches from RUN to CUTOFF commanded or uncommanded? The last minute relight effort also runs counter to a deliberate shut down. It also bears mention that no guarded switch with pull detent will roll back on its own. This is where the crux of the investigation lies, going forward. See the highlighted extract from the report attached below: Safety bulletins unactioned It is apparent from the report that Boeing in their wisdom decided that providing such a critical switch (with potential for inadvertent operation) with a 'pull-detent' or mechanical lock should be a Special Airworthiness Information Bulletin rather than an Airworthiness Directive or Alert Service Bulletin. This by itself is questionable. Air India, the Maharaja who had just found its new clothes, decided to not implement Boeing's SAIB NM-18-33, thus setting the stage for this disaster (as it appears at this stage). Another line from the report, viz. 'there has been no defect reported pertaining to the fuel control switch since 2023 on VT-ANB' raises more questions than it answers. This line when read with reference to SAIB NM-18-33 of Dec 2018 reveals possible operation of fuel switch in an unintended manner since Air India had not complied with the SAIB. These switches also double up as engine start switches and are used only twice in a normal flight (one for starting, second for switching off at the ramp). Without acting on SAIB NM-18-33, did Boeing and Air India set up the 'black swan' event of uncommanded or inadvertent operation of the two switches is something AAIB will have to probe deep into. On first look, this is going the B737 Max route. The usual suspects — Boeing, FAA, DGCA, and a transitioning major carrier, are at play. So are pilot shaming, conspiracy theories, scale of tragedy & dependency on Boeing, NTSB & FAA on crucial aspects related to airworthiness and certification of a critical flight/engine control. A lot to unpack. Are we prepared? AAIB has a lot on their plate with this crash. It will test the bandwidth of this nascent organisation that runs key departments on borrowed expertise. Implanting a serving air force officer cannot be expected to lift the agency out of the deep morass DGCA and MoCA have created for itself and its progeny over the years. My immediate thought after news of the crash broke was 'are they even prepared for the scale of this tragedy?' People vested with such serious, technical, investigative work should not be beholden to ministers & bureaucrats. William P. Rogers, during a pause in the proceedings of the Rogers Commission on the Space Shuttle Challenger disaster of Jan 28, 1986 famously said of an empaneled Nobel Laureate SME member: 'Feynman is becoming a real pain in the ass.' As per AAIB's preliminary report, VT-ANB crash investigation team comprises 'Mr. Sanjay Kumar Singh as Investigator-in-Charge, Mr. Jasbir Singh Larhga as Chief Investigator and, Mr. Vipin Venu Varakoth, Mr. Veeraragavan K and Mr. Vaishnav Vijayakumar as Investigators. Experienced Pilots, Engineers, Aviation Medicine Specialist, Aviation Psychologist and Flight Recorder Specialists have been taken on board as Subject Matter Experts (SMEs) to assist the Investigation in the area of their domain expertise'. The area of expertise of investigation team or SMEs has not been mentioned, but one expects AAIB to cover all bases while also ensuring no conflict of interest. Under a MoCA run by bureaucrats, with a regime known to be economical with facts & hard data, the only hope for a deep, impartial investigation rests with at least a few 'pain in the a**' members who are loyal only to science and truth, not any maharaja (emperor). Let us not forget how biased media & Boeing aficionados tried to push the blame for 737 Max on Lion Air & Ethiopian pilots till evidence hit them on the nose. It is far too early, indeed malicious, to blame pilots of AI171. Let AAIB do its work. GoI on its part must ensure zero interference. Much as the preliminary report sounds ominous in content, stranger things have happened. Remember 'kid in the cockpit'? AI-171 is a national tragedy, but hopefully one that should spur India to set up an independent transportation safety board that will serve the cause of promoting safety across ALL modes of transportation, including space travel. The existing system of silos is incompatible with needs & aspirations of 1.4bn. In closing, with the available information at this stage, I complement AAIB India on not bucking to pressure, quietly doing their duty and presenting factual information within the prescribed framework of ICAO Annex 13. I look forward to the final report with a hope spelt out by former NTSB Chair Robert Sumwalt: 'human error should be the start point of any investigation and not its end'. Cdr KP Sanjeev Kumar is a former Navy test pilot and alumnus of Air Force Test Pilots School, ASTE. He has flown over 5,000 hours on 24 types of aircraft and helicopters. He calls himself 'full-time aviator, part-time writer' and blogs at Views are personal.
India Gazette
an hour ago
- India Gazette
"Not satisfied": AI171 crash victim's father demands deeper probe, stricter action
Mehsana (Gujarat) [India], July 13 (ANI): The father of Sanket Goswami, a 19-year-old student who died in last month's Air India AI171 crash, stated that he was 'not satisfied' with the preliminary investigation report released by the Aircraft Accident Investigation Bureau (AAIB), and requested the government to conduct a 'thorough investigation'. He also urged the government to take strict action against those responsible for the incident. Sanket's father, Atul Goswami, told ANI, 'My son was 19 years old... My family is living under such difficult circumstances. We used to rely on my son a lot. He was going to London for three years to get his degree. Our whole family relied on him... We are not satisfied with the report. We request the government to conduct a thorough investigation and strict action be taken against the responsible parties...' The AI171 crash took place on June 12, when the London-bound Air India Boeing 787-8 aircraft crashed shortly after takeoff from Ahmedabad's Sardar Vallabhbhai Patel International Airport. The aircraft hit a hostel building at BJ Medical College, killing 241 of the 242 people on board. Among the victims was former Gujarat Chief Minister Vijay Rupani. It is one of the worst air disasters in India in recent years. On Friday, the AAIB released its preliminary report into the crash. It described a critical situation that developed just 90 seconds after takeoff, when both engines shut down unexpectedly during the climb. This led to a loss of thrust and a rapid drop in altitude. Flight data from the aircraft's Enhanced Airborne Flight Recorder (EAFR) showed that the fuel cutoff switches for both engines were accidentally moved from RUN to CUTOFF within one second of each other, shortly after takeoff. One pilot was heard asking the other, 'Why did you cut off?' to which the response came, 'I did not.' The sudden shutdown caused the Ram Air Turbine (RAT) to deploy, but the aircraft began losing height immediately and could not stay in the air without engine power. According to the AAIB, the pilots tried to relight both engines by switching the fuel systems back on. While Engine 1 started to recover, Engine 2 did not stabilise. Even though the aircraft briefly reached 180 knots, it continued to descend. The final distress call, a 'MAYDAY', was sent at 08:09 UTC, seconds before the crash. (ANI)
