Air India Ahmedabad crash probe: 5 things to know from the preliminary report
The Annex 13 of Chicago Convention, to which India is a signatory, mandates that states in charge of an investigation must submit a preliminary report to ICAO (International Civil Aviation Organisation) within thirty days of the date of the accident. Preliminary reports can be marked confidential and it depends on the investigation state's discretion if they should be made public. ICAO also mandates that the final report should be made publicly available as soon as possible and if possible within twelve months.
However, these are advisories and not rules. Recently China is reported to have refused making the crash report of China Eastern flight MU5735 public citing (it could) 'endanger national security and societal stability'.
The last two crashes in India have been the Air India Express crash at Kozhikode on 7 August 2020, with the final report submitted on 13th January 2021 and the Mangalore crash on 22 May 2010, when the final report came out in November that year. These two crashes were in the landing phase, while the Air India crash at Ahmedabad was within seconds of lifting off from the runway.
The preliminary report throws light on these five things
There has been quite a lot of speculation on what were the last words from the pilots of the AI171, with various sources being cited by each one. Turns out the last words were only 'Mayday, Mayday' and the pilots did not speak about loss of power or anything else.
The aircraft which crashed, VT-ANB did not have any critical items under MEL or Minimum Equipment List. The entire MEL list was within the timeline limits. In aircraft, a Minimum Equipment List (MEL) is a document that outlines the minimum equipment required for an aircraft to legally operate with certain inoperative systems or components.
It allows for safe operation even when some equipment is not fully functional, provided specific conditions are met and the aircraft complies with the MEL's limitations.
The MEL is specific to an aircraft type and operator and is derived from a Master Minimum Equipment List (MMEL) provided by the aircraft manufacturer.
Immediately after take off, AI 171's Engine 1 and Engine 2 fuel cutoff switches transitioned from RUN to CUTOFF, one after another. In the cockpit voice recording, one of the pilots is heard asking the other why he cut off. The other pilot responded that he did not do so.
The AAIB preliminary report mentions how the fuel cutoff switches again transitioned from CUTOFF to RUN with efforts made to relight the engine, one after another.
As per the EAFR (Enhanced Airborne Flight Recorder), the Engine 1 fuel cutoff switch transitioned from CUTOFF to RUN within seconds of pilots talking about cut-off.
The APU Inlet Door began opening thereafter, consistent with the APU Auto Start logic. Thereafter the Engine 2 fuel cutoff switch also transitions from CUTOFF to RUN.
When fuel control switches are moved from CUTOFF to RUN while the aircraft is inflight, each engine's full authority dual engine control (FADEC) automatically manages a relight and thrust recovery sequence of ignition and fuel introduction.
The EGT (Exhaust Gas Temperature) was observed to be rising for both engines indicating relight. 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 and re-introduced fuel repeatedly to increase core speed acceleration and recovery.
The preliminary report on Air India plane crash does not point to any recommendations for either Boeing, the manufacturer of the plane type or GE, the manufacturer of the engines which powered the plane.
With the preliminary report out, the focus will shift on what led to the movement of switches of the Air India AI171 plane that crashes moments after take-off in Ahmedabad. If it was manual, why did that happen and which of the two pilots did it along with ways to ensure this does not repeat again.
Both the government and Air India have been criticised for the way the crash was handled. From a single press conference and lack of regular briefings to suspense over where the Black box is and the time taken to get it from Ahmedabad to Delhi, a lot could have been handled professionally. The airline on the other hand started on the wrong foot with the speech from the Chief Executive Officer being accused of plagiarism from the American Airlines incident earlier this year.
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NDTV
an hour ago
- NDTV
Should Changing Switches Have Been A Must? On Air India Crash, Expert Says...
An advisory had been issued by the Federal Aviation Authority (FAA) in 2018 about fuel cutoff switches moving without any force after they get worn out and, in hindsight, it would have been better if changing them had been made mandatory, a former director general of the Aircraft Accident Investigation Bureau (AAIB) has said. Speaking to NDTV on Saturday, Group Captain Aurobindo Handa (retired), former director general of the AAIB, also said that he was with the Air Force where no chances are taken on ejection seats and engines and, going by that, "a better application of mind" should have taken place. In its preliminary investigation report on the Air India Dreamliner crash in Ahmedabad, the AAIB noted that both engines of the plane had shut down mid-air within seconds of take-off and both fuel cutoff switches moved from 'RUN' to 'CUTOFF' position within a second of each other. This meant no fuel was reaching the engines, causing the plane to lose thrust. The report said that, in the cockpit voice recording, one pilot can be heard asking, "Why did you cut off?" and the other replies, "I did not". Group Captain Handa - who handled at least 100 such investigations, including the August 2020 crash of an Air India Express flight from Dubai to Kozhikode- said it is "extremely difficult" for both fuel cutoff switches to move together and then pointed to the 2018 advisory. "Way back in December 2018, there was an advisory issued by Boeing through the FAA that these gated switches get worn out over a period of time and they can move without any force. They had suggested that they should be checked and, in case they are worn out, they should be changed. But they recommended an on-condition change. On-condition means that if you see a worn-out valve, change it," he pointed out. "But what now, in hindsight, all of us are thinking is that it would have been better had they made it a mandatory change at that point in time... at the same time, there is a saying everyone is wise in hindsight. But, being from the Air Force, let me tell you one thing very clearly: On ejection seats and on engines, we do not take a chance. So, going by that, since this pertained to engine controls and flame-out in air, I think better application of mind should have taken place," the former AAIB chief said. He continued, "When this advisory was issued in the form of a bulletin, the Directorate General of Civil Aviation should have called the senior pilots operating the variants of Boeing and should have told them 'This bulletin has come, please apply your mind and tell us what we should do. So, automatically, there would have been a better collaborative decision... we would have arrived at a better decision." Transparency Group Captain Handa praised India's leadership, in civil aviation and otherwise, for coming out with the preliminary investigation report, saying it was important given how many lives were lost in the crash and because it will give grieving relatives some sense of what happened. The Air India Dreamliner 787-8 - operating as AI flight 171 to London, had crashed into a medical college's hostel in Ahmedabad on June 12, just 32 seconds after taking off. One passenger had miraculously survived, but all the other 241 people on board and at least 20 on the ground were killed. On whether the crash raises concerns about the accountability of the manufacturer, operator or regulatory bodies, the former AAIB chief said it is hard to say at this point because the investigation is only in its initial stages. "We should wait for at least four, five months because it is a long-drawn process... The evidence is comparatively low in this crash," he sai, urging everyone to refrain from speculation.
The Hindu
2 hours ago
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Air India says will review preliminary plane crash report with pilots
Air India on Saturday said it will take on board its pilot community by holding dedicated sessions in the coming days to review the preliminary investigation report of the June 12 Ahmedabad plane crash. The 15-page preliminary report by Aircraft Accident Investigation Bureau (AIIB), released early on Saturday, has found that the fuel supply to both engines of Air India flight AI171 was cut off within a second of each other, causing confusion in the cockpit and the airplane plummeting back to ground almost immediately after taking off. On June 12, the London-bound Boeing 787 Dreamliner began to lose thrust almost immediately after taking off from the Ahmedabad airport and ploughed into a medical college hostel, killing all but one of the 242 persons onboard and another 19 on the ground in the deadliest aviation accident in a decade. 'Preliminary investigation report has been officially released in the recent tragic accident involving our flight AI 171 from Ahmedabad to London Gatwick on June 12. As aviation professionals, we understand top importance from every safety event is the learning to ensure safe skies,' Air India senior vice president for flight operations, Manish Uppal, said in a communication to pilots. This tragedy, he said, has deeply influenced the aviation fraternity and Air India pilot community. 'The initial report gives the airline an initial insight. This is not the last word, but an important step in identifying factors and ensuring that all possible measures are taken to prevent such a tragedy from reoccurring,' he said in the communication. In the communication, he also said that pilots are trained to stay under pressure, to continuously learn, and to act decisively when it matters most, adding, 'Let us apply the same now. Together, we will reflect, react and rise more than before.' 'We will organise a dedicated session in the coming days to review the report together,' he said in the communication. The preliminary investigation report into the disaster revealed that fuel-control switches of the two engines moved from the 'run' to the 'cutoff' position, within the space of one second, leading to immediate loss of altitude. In the cockpit voice recording, one pilot is heard asking the other why he cut off the fuel. The other denied having done so. The investigation was conducted with assistance from the U.K.'s Air Accident Investigation Branch and the U.S. National Transportation Safety Board. Aviation experts have said it is difficult for pilots to inadvertently move the fuel switches, as there is a little mechanical gate built into the switch. Switches need to be lifted up over this little gate to shut off supply. They also asked why the report made no reference to cockpit camera footage. The Airlines Pilots Association of India raised the issue with the report, saying the investigation is 'shrouded in secrecy', appears to be biased against the pilot and has come to a conclusion hastily.
India Gazette
2 hours ago
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"Pilots did everything right": Captain Umang N Jani on AI 171's crash report
Ahmedabad (Gujarat) [India], July 12 (ANI): Captain Umang N Jani, Head of Department (HoD) Aviation at Indus University, on Saturday said that the pilots of the crashed Boeing 787-8 Air India flight 171 did 'everything right' by attempting to restart the engines. He said that the preliminary report by the Aircraft Accident Investigation Bureau (AAIB) mentions that the fuel switch was at the 'run' position. 'The pilot did everything right. It is part of the training that when engines fail, you attempt to restart them. The report also suggests that the fuel switch is in the run position. This aircraft has an FADEC (Full Authority Digital Engine Control) system in place. When you start the engine, there is a complete sequence that needs to be followed, and this system automatically follows this entire sequence,' Captain Jani told ANI. He informed that the engines stop working when the fuel supply stops, which makes such types of incidents possible. He said that the fuel switch is situated on the throttle quadrant in the aircraft, which was found to be in the 'run' position, indicating that the pilot tried to restart the engine. 'It mentions fuel cutoff. When the fuel supply stops, both engines stop working, and then the type of incident that happened is possible. If I talk about the throttle quadrant, there is a fuel cutoff switch here. In the crash, it has been found that the fuel switch was in the 'run' position. It seems that the pilot tried to restart the engine. This process of whether to supply fuel to the engine is controlled manually from the cockpit,' Jani added. 'Generally, the fuel switch is not put on cutoff after takeoff. This is done in two situations: normal and emergency. You put the switch on cutoff once the aircraft has landed and parked during normal times,' he stated. The Captain said that further investigation was required into the flight crash. 'This is a preliminary report. Now, there may be further investigation and the final report that will come, it is possible that we may get to see more information and more details in it,' Jani said. The AAIB's Preliminary Report, released on Friday, said that both the engines of the aircraft were moved from 'run' to 'cutoff' in quick succession, which resulted in the fuel supply being cut off. The report says that in the cockpit voice recording, one of the pilots is heard asking the other why he did the cutoff, which the other pilot denied ever doing so. '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,' the preliminary report said. 'In the cockpit voice recording, one of the pilots is heard asking the other why he cut off. The other pilot responded that he did not do so,' the report added. As per the Enhanced Airborne Flight Recorder (EAFR) accessed by the AAIB, engine 1's fuel cut switch transitioned from 'cutoff' to 'run' at about 8:08:52 UTC (Coordinated Universal Time), and at 8:08:56 UTC, Engine 2's fuel switch also went from 'cutoff' to run'. According to the report, just 13 seconds later, at 8:09:05 UTC, one of the pilots transmitted the Mayday call, which the Air Traffic Control Officer (ATCO) enquired about, but did not receive a reply. Shortly after, the aircraft was observed crashing outside the airport boundary, and the emergency response was activated. The Airline Pilots' Association of India on Saturday also called for a 'fair, fact-based inquiry,' into the incident and rejected the 'tone and direction of the investigation' which suggested a bias towards pilot error. 'The report was leaked to the media without any responsible official signature or attribution. There is a lack of transparency in investigations as investigations continue to be shrouded in secrecy, undermining credibility and public trust. Qualified, experienced personnel, especially line pilots, are still not being included in the investigation team,' the association said in a statement. Notably, Minister of State for Civil Aviation Murlidhar Mohol urged people not to draw conclusions based on the preliminary report. While speaking to mediapersons, the MoS said, 'The AAIB has brought out a preliminary report. This is not the final report. Until the final report comes out, we should not arrive at any conclusion. AAIB is an autonomous authority, and the ministry does not interfere in their work.' (ANI)
