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Air India Chief Says Preliminary Crash Report Raises Fresh Questions 101

Posted by msmash from the unsolved-mysteries dept.
Air India's chief executive urged staff to avoid drawing premature conclusions about what caused one of the airline's Boeing triangle jets to crash last month, after a preliminary investigation ruled out mechanical or maintenance issues, turning attention to the pilots' actions. WSJ: Campbell Wilson told staff that the probe into the crash was "far from over," according to an internal memo, reviewed by The Wall Street Journal, in which he set out some of the findings of a report issued by India's Aircraft Accident Investigation Bureau at the end of last week.

Wilson's memo didn't mention one of the AAIB's findings: that the airplane's fuel-control switches had been turned off one by one, seconds after takeoff, starving both engines of fuel. The switches, which sit between the two seats in the cockpit, were turned back on about 10 seconds later, but the engines apparently couldn't fully restart and gain thrust fast enough, the report said.

The crash of the London-bound Boeing 787 Dreamliner killed all but one of the 242 passengers and crew on board, as well as 19 people on the ground, when the plane slammed into a residential area beyond the airport in the Indian city of Ahmedabad. In the memo, Wilson said "over the past 30 days, we've seen an ongoing cycle of theories, allegations, rumours and sensational headlines, many of which have later been disproven."

Air India Chief Says Preliminary Crash Report Raises Fresh Questions More | Reply

Air India Chief Says Preliminary Crash Report Raises Fresh Questions

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  • I don't see anything new, compared with the previous story about this crash.

    https://tech.slashdot.org/stor... [slashdot.org]

  • I think I remember the angle of attack sensor being the pilot's fault for a while until two or three planes crashed

    • Well ultimately it still was the pilots fault as the pilot wasn't aware which system was malfunctioning, how the system worked, and didn't take appropriate action to correct for the problem. That is the reason why the FAA required recertification of all pilot training programs for each individual airline before allowing that airline to resume flying their 737 MAX 8s. See Appendix A https://www.faa.gov/documentLi... [faa.gov]

      Yeah the hardware was fucking rubbish, but there ultimately still was an element of pilot erro

      • Re: (Score:2, Informative)

        by Uberbah ( 647458 )

        Yes, it's the pilots fault for not having ESP training to know Boeing was corrupt, greedy and putting out faulty products and lying about retraining for profit. Inset eyeroll emoji.

        • Re: (Score:2)

          by Creepy ( 93888 )

          There is something seriously wrong with this crash, the pilot didn't pull in the landing gears and seems to have intentionally crashed it by descending intentionally into a housing area. Sorry, but blaming Boeing, I really want to see the evidence. No Dreamliner has ever crashed until this, and everything is suspect. Having door bolts blow out on a different plane is a totally different issue. Sorry, but I've worked with Boeing for years and while they have fucked up, they've tried to put safety first IMO.

          • There is something seriously wrong with this crash, the pilot didn't pull in the landing gears and seems to have intentionally crashed it by descending intentionally into a housing area.

            The fuck?
            Landing gear are usually pulled up ~10 seconds after rotate.
            This plane lost all power 3 seconds after.
            1) They would never have retracted, because they did not have a positive rate of climb 10 seconds after rotate.
            2) They couldn't have, even if they wanted to- velocity was far too low for the RAT to provide the power for it by the time it would have been appropriate to.
            What in the flying fuck would you have liked the pilots to do with their unpowered plane to avoid the housing area?

            Sorry, but I've worked with Boeing for years and while they have fucked up, they've tried to put safety first IMO.

            Not doing a

          • Re: (Score:1)

            by Uberbah ( 647458 )

            And the hundreds of defective parts that disappeared and most likely were installed on planes? Or the workers literally jumping up and down on top panels to get them to fit? This crash may have happened from pilot errors, but there's still a whooooole lotta Boeing execs who should be in prison.

      • It was never the fault of the pilot.
        Boeing specifically sold the MAX as not requiring training for the MCAS- both in advertising, and regulatory requirements.

        A pilot that was not required to be trained due to corruption of the regulatory regime has not made an error, short of being able to divine truth from corporate chicken bones.

        • False. It was the immediate fault of the pilot. But pilot error was never the root cause as they weren't given the required information in the systems and processes in place to handle the situation.

          But immediately pilot error very much was identified and is part of the recommendation to address by the FAA.

      • Re: (Score:2)

        by gweihir ( 88907 )

        No. It was _not_ the pilot's fault. Boeing had neglected to tell the pilots about the new system and they had no chance to find out that a system they did not know about was malfunctioning.

        Your usual level of complete lack of insight, though.

        • You're confusing fault and root cause. The fault was in the system, the fault was in the pilot not correcting for the problem, the fault was in Boeing not doing the thing right. The root cause all lead to Boeing. Pilot fault very much was not just initially but also finally implicated in the FAA report.

    • India requires switch inspection, no argument. Would expect this to be done pronto regardless but good to mandate just in case. Was brushed off as an advisory. Next up since limited audio released there are questions on whether this was intentional or other. Video footage would help so how about installing. A bit late but for next time and to calm folks who need to fly.
  • What the hell is a "triangle jet"? I see MSN edited the story to remove the word "triangle"...

  • 08:08:42 Engine 1 fuel switch flips to CUTOFF
    08:08:43 Engine 2 fuel switch flips to CUTOFF

    A question: What is the the granularity of those times given? I get the impression that it is one second, but there is quite a difference between
    08:08:42.999 Engine 1 fuel switch flips to CUTOFF
    08:08:43.000 Engine 2 fuel switch flips to CUTOFF
    and
    08:08:42.000 Engine 1 fuel switch flips to CUTOFF
    08:08:43.999 Engine 2 fuel switch flips to CUTOFF
    One of those is essentially "simultaneously" and the other pretty much two se

    • 10ths of a second means significantly more data to be recorded, especially for continuously measured values. But really what is the outcome difference you're looking for? If this were a purely software error then the timing wouldn't be 1 second off (or even 1ms off). 1 second granularity is enough to tell us they changed state mechanically, whether by hand or otherwise. What additional info are you postulating to see here?

      • Are these values "continuously measured" or is the logging event driven?
        As to what the difference between simultaneous and two seconds, the "simultaneous" end of the scale is a clear indication that the switch locking mechanism was broken.

        • Digital inputs are usually event driven, but the in flight data recorder also continuously records data from analogue signals as well including things such as the oft talked about AOA. The question is, are you proposing a defined difference between the way different inputs are recorded temporarily, e.g. 10x as often for digital events vs analogue, or just switches? That can be fine even if it ads complexity to the statement of requirements, but you have to be clear what you're measuring.

          As to what the difference between simultaneous and two seconds, the "simultaneous" end of the scale is a clear indication that the switch locking mechanism was broken.

          That data may alread

    • They don't give time stamps for the fuel cut-offs.
      Rather, the preliminary report says:

      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 granularity for the switches might be bad, but the engine core speed is 0.125 seconds, so they should be able to infer if there was a meaningful gap between the deactivations.

      • I previously read that the switches moved in adjacent 0.1(25)ms time windows. It might be that the movements were 0.01ms apart or almost 0.25ms.
        • This is not in the preliminary report.
          If true, it would be very interesting, and would imply 1 of two things.
          1) The locking mechanism failed on (both) switches, or was installed improperly- and nobody noticed this before hand, and it was all an accident.
          2) It was ultra malicious, as the operator used both hands to unlock and move the switches.

          However, I think it's probably not true since it is not in the preliminary report.
          • That's what was being discussed in a few aviation-related forums a couple of days ago. The preliminary report says "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 use of just one timestamp when everything else that happened at a different timestamp is noted suggests that both were moved to cutoff at 0

            • That's what was being discussed in a few aviation-related forums a couple of days ago.

              I'd avoid those morons like the plague.
              They're the same dumbshits that propagated the hypothesis that the pilots lifted the flaps instead of the landing gear, even though at no point should that plane have lifted its landing gear in that flight profile.

              The use of just one timestamp when everything else that happened at a different timestamp is noted suggests that both were moved to cutoff at 08:08:42, but it's a bit ambiguous.

              No, it is not ambiguous in even the slightest bit.

              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

              That can only be read one way:
              The timestamp for N1 cut-off is 08:08:42, and N2 is 08:08:43.
              There is a time gap of 01 sec.

              • Re: (Score:2)

                by q_e_t ( 5104099 )

                That's what was being discussed in a few aviation-related forums a couple of days ago.

                I'd avoid those morons like the plague.

                Mostly commercial airline pilots.

      • Even if they were 1s apart, then given muscle memory it could be possible for someone to flip them without being fully aware. Errors in control usage like that sadly happen all the time. It may or may not have been the case here. Time and further investigation will tell. It seems a bit early to call it right now. Checking switches in the meantime might be a useful precaution even if it's not the cause.
        • Muscle memory is unlikely, since normal operation requires unlocking of them. You would not develop muscle memory to skip the locking mechanism.
          Each switch, under normal operation, must be lifted, rotated, moved, rotated, dropped- individually.
          • People are capable of surprisingly complex automatic actions. Normally on the more positive side, people report carrying out a series of trained actions when under stress that they later report they have no conscious knowledge of performing. It happened to a friend of mine who, in a car crash, put the car in neutral, parking brake on, turned the car off, removed the key and got out before collapsing. He doesn't remember taking those actions but since the car had the parking brake on, engine off, he must hav

  • A 2018 advisory was issued for those switches (Score:4, Informative)

    by david.emery ( 127135 ) on Monday July 14, 2025 @03:01PM (#65520284)

    See https://ad.easa.europa.eu/blob... [europa.eu] That's an old advisory (December 2018) that applies across a variety of Boeing aircraft. It should have been the case that all operators did and documented the required inspections.

    Model 717-200 airplanes; Model 737-700, -700C, -800, and -900ER
    series airplanes; Model 737-8 and -9 airplanes; Model 747-400, -400D, -400F, -8, and -8F series
    airplanes; Model 757-200, -200CB, -200PF, and -300 series airplanes; Model 767-200, -300, -
    300F, -400ER, and -2C series airplanes; Model 787-8, -9, and -10 airplanes; Model MD-11 and
    MD-11F airplanes; and Model MD-90-30 airplanes of the potential for disengagement of the fuel
    control switch locking feature.

    1) Inspect the locking feature of the fuel control switch to ensure its engagement. 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.
    2) 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: Replace the
    fuel control switch with a switch having P/N 766AT614-3D, which includes an improved
    locking feature.

    It's my understanding that part of the cockpit was recovered pretty much intact, so I'm sure there'll be forensic investigation into those switches.

    • Re:A 2018 advisory was issued for those switches (Score:5, Informative)

      by sirket ( 60694 ) on Monday July 14, 2025 @04:38PM (#65520582)

      The 787 switch is slightly different from the 737 switches and there have been no known cases of them being tripped accidentally on a 787.

      Additionally, the control stand on that specific 787 was supposedly replaced a couple of times over its life so it likely would have received updated switches already.

      Plus defective switches would not explain why one switch was slipped and then the other.

      • Of note is the unit with these switches were actually replaced twice since the 2018 advisory. Once in 2019 and once in 2023.

        But there is insufficient information to indicate that the switches were not slipped concurrently. Data is recorded once per second, but events in time for switches are not discrete, they are in unknown states for many 10s of ms at the time of actuation. Just the programmatic delay of reading one input from a system then the next could put the switch in a different recorded state.

        I act

    • From the preliminary report

      "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. 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."

      So the inspection recommended by the 2018 advisory you

    • Your understanding is wrong. There's pictures of the switches included in the report https://aaib.gov.in/What's%20N... [aaib.gov.in] they are very much burnt to a crisp. It may not be possible to draw any conclusions as to whether the locking mechanism was functional.

      As for your FAA advisory it is important to read the very the very first sentence at the top: "This is information only. Recommendations aren’t mandatory." It was only a recommended advisory. No airline was required to take action, and Air India have

      • The more interesting observation is that the part containing those 2 switches has been replaced twice since the advisory was issued. So presumably the questionable switches in the advisory were not used in the much newer replacement part.

        I don't know what those parts are made of, but if they're metal, they might well survive. We'll have to wait for the final accident report to see what they learn about that aircraft's switches.

  • This was not this plane's first flight. For both to have a problem at the same time, but never before, is highly unlikely.
  • At that particular time after take-off. I was listening to NPR story this weekend. Airline investigator was talking about how after a particular velocity on the runway, the jet must take off there is no room to abort. The plane in question was past that point and in the air. Also known that the jet could not get lift from gliding, i.e., one engine has to have fuel to get lift. Why allow both fuel switches to be shut off at this point? Surely modern craft has so many safety lockouts yet not this one.

    • Re:Seems strange to allow user input (Score:5, Insightful)

      by smooth wombat ( 796938 ) on Monday July 14, 2025 @04:40PM (#65520590) Journal
      Why allow both fuel switches to be shut off at this point?

      Fire? From my perspecitve (non-technical, non-aeornautical) you should not want something like this to be locked down. You should always allow for something unexpected to occur which would necessitate moving these switches in all circumstances. Locking them down would seem to deprive the pilot/co-pilot the ability to react to a situation.
    • Actually, it might be quite sensible to have some sort of interlock that causes the fuel switch to be locked in the RUN position while the power lever for that engine is at the full thrust position. Then needing to turn fuel off due to a "Fire" situation becomes a training procedure issue. i.e. In case of engine fire, step 1. Identify which engine is on fire. Step 2. Pull Power Lever back to idle. Step 3. Fuel switch to "Off". I can't think of a good reason why you would want to keep the power lever forwar

      • I can't think of a good reason why you would want to keep the power lever forward when you were about to turn off the fuel anyway...

        One reason is to have the engine try to burn the fuel in the lines until the residual pressure of the pumps bleeds off. If there's a fire caused by a leak between the pumps and engine, this is the best course of action rather than let that fuel get entirely pushed out of the leak. It will also give you a few extra seconds of power, which might be the difference in getting back to the airport or crashing just short.

        Aviation safety usually is geared to giving the pilots the most options in an emergency. If th

    • These are safety systems. You can't consider what situation they are in for locking mechanisms. Imagine taking off and having a bird strike in both engines. Fuel cut-off is standard procedure then, and if it weren't in a city (as it would be in some airports) you could glide into a semi-controlled crash landing.

      You always need to consider what situation you would allow something to be bypassed and if that could have knock on implications for how it would be used. Note there were already 2 independent mechan

  • What is that...?

  • Release the audio (Score:3)

    by hambone142 ( 2551854 ) on Monday July 14, 2025 @08:04PM (#65521150)

    India is purposely obscuring the situation. They KNOW who was talking but they won't say. Each pilot has a separate Com. channel.
    I suspect there's a lot of information on the cockpit voice recorder that they're filtering out. Again, they won't even say "who said what".
    They're hiding something and it's likely that the Captain did the deed because the First Officer was flying the plane into a rotation keeping busy.

    • The pilots names sound Hindu + Christian. However, it could be probable sabotage by Turkish ground maintenance company. Turkey supported Jihadi Muslim Pakistan/Pukistan's Islamic terrorist atfack against Hindu + Budfhist Yogic India.

      Radical Islam is the snake hiding in the grass
      Moderate Islam is the grass hiding the snake. Mamdani is a traitor to India+USA, a viper in human clothing, he celebrated the terrorist attacks by Islamic terror rogue nation Pakistan/Pukistan against freedom loving dharmic/democrati

    • Each pilot has a separate Com. channel.

      The conversation wasn't the result of recording over comms, it was the ambient recorders. Stop jumping to conspiracies. India involved the NTSB and Boeing to read out the data recorder. Do you think an American organisation and an American company give a fuck about some pilot conspiracy?

      Let the investigation conclude. It changes nothing for you to wait. The dead people aren't getting any deadder.

    • Re: (Score:1)

      by ralic ( 1256888 )
      Why? The audio is no evidence of who performed the action. I could move the cheese and then ask you why you moved the cheese, leading to you responding that....

  • "after a preliminary investigation ruled out mechanical or maintenance issues,"

    Totally false reporting. Nothing was ruled out. It's entirely possible that there was something faulty about those switches. What is new is that pilots are squawking at laying the blame at pilots' feet.

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