Air India Chief Says Preliminary Crash Report Raises Fresh Questions
- Reference: 0178376070
- News link: https://news.slashdot.org/story/25/07/14/187209/air-india-chief-says-preliminary-crash-report-raises-fresh-questions
- Source link:
> 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."
[1] https://www.msn.com/en-us/travel/news/air-india-chief-says-preliminary-crash-report-raises-fresh-questions/ar-AA1IzPHR
[2] https://tech.slashdot.org/story/25/06/12/1224214/air-india-boeing-787-carrying-242-passengers-crashes-after-takeoff
[3] https://tech.slashdot.org/story/25/07/12/0326234/before-air-india-boeing-787-crash-fuel-switches-were-cut-off-preliminary-report-says
Remember the 737 Max (Score:2)
I think I remember the angle of attack sensor being the pilot's fault for a while until two or three planes crashed
Re: (Score:2)
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 [1]https://www.faa.gov/documentLi... [faa.gov]
Yeah the hardware was fucking rubbish, but there ultimately still was an element of pilot erro
[1] https://www.faa.gov/documentLibrary/media/Notice/N_8900.569_FAA_Web.pdf
Re: (Score:2)
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.
Triangle jet? (Score:1)
What the hell is a "triangle jet"? I see MSN edited the story to remove the word "triangle"...
Granularity (Score:2)
> 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
Re: Granularity (Score:1)
It does not tell us they were not flipped with one hand at the same time, no.
Re: (Score:3)
Not necessarily. The granularity matters and the clock/log accuracy matters.
[SNIP]
08:08:42.999 Engine 1 fuel switch flips to CUTOFF
08:08:43.000 Engine 2 fuel switch flips to CUTOFF
[SNIP]
. . . is essentially "simultaneously" . . .
[SNIP]
And if the accuracy was +-1/1000sec OR +-100/sec (not uncommon for a log)?
Re:Granularity (Score:4, Interesting)
Actually it doesn't. That's the problem with granularity, you're chasing the difference between state (which is never defined at a single point for a switch) and scan time of the input system. If one switch is triggered within 1ms from the other, they have been triggered simultaneously, with any resulting error being the result of contact bounce. For a system that has a scan time of 1 second, it could very well have been that one switch had contacts which hadn't settled one side of the second mark while the other had to wait for the system to process its input logic again 1 second later. That's the OP's point. I don't think it makes any difference to the outcome or investigation, but it is important in some situations.
I have a real world example of this which I have experienced. On a Triconex industrial safety system there is a single switch that sets the system to OFF, RUN, REMOTE, and PROGRAM mode. It spends most of it's time in RUN, but I had to download some new code to it so I went to the system and flicked this switch to RUN. Unluckily as I flicked this single switch 2 of the system's 3 main processors saw one contact close 125ms after the 3rd processor, that was enough to trigger a diagnostic error and force the processor to reboot raising all hell in the control room as system fault alarms were coming up. One switch only, two different states in the same system.
Re: (Score:2)
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?
Re: (Score:2)
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.
A 2018 advisory was issued for those switches (Score:4, Informative)
See [1]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.
[1] https://ad.easa.europa.eu/blob/NM-18-33.pdf/SIB_NM-18-33_1
Re: (Score:3)
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.
Re: (Score:2)
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
City under the takeoff/approach path (Score:2)
is particularly bad city planning. There should always be open space like water or farm land.
Re: (Score:3)
Absolutely. They should move San Diego, it's in the way of landings and take-offs.
Re: (Score:2)
When I was in Marine Corps boot camp in San Diego we called the constant landing and taking off planes freedom birds.
Re: (Score:2)
I can't speak to this particular airport... but, for most of them, I suspect you'd find those areas were mostly open space when the airport was first designed and built.
Re: (Score:2)
Luke AFB, nominally located in Glendale, AZ, was built long before housing was built as close to it as ii is today. Mostly farms back then. In time, of course, development ensured, and now many residents complain bitterly about jet noise. They never were told, nor realized, that they bought their house next to an active Air Force base that was there decades ago, in 1941.
Until 2019 it was in Surprise, AZ city ordinance that realtors or sales agents needed to have on their person a map of the Luke AFB locale,
Re: (Score:2)
We'll inform Chicago to stop using every runway at O'Hare then, because you say so. Though, it may be a bit of a discussion since they have so many aircraft land and take off without crashing on a daily basis. But you said they shouldn't do that any more, so we'll just stop a few billion dollars a day of commerce!
Very unlikely to be a problem with the switches (Score:2)
This was not this plane's first flight. For both to have a problem at the same time, but never before, is highly unlikely.
Seems strange to allow user input (Score:2)
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: (Score:2)
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.
"Boeing triangle jet" (Score:2)
What is that...?
Nothing new (Score:2)
I don't see anything new, compared with the previous story about this crash.
[1]https://tech.slashdot.org/stor... [slashdot.org]
[1] https://tech.slashdot.org/story/25/07/12/0326234/before-air-india-boeing-787-crash-fuel-switches-were-cut-off-preliminary-report-says
Re: (Score:2)
I doubt it considering the voice recordings that exist of the pilots. Radical Jihadists aren't exactly shy about proclaiming their acts. It sounds like a pilot did something incredibly stupid that they tried (and unfortunately failed) to fix, for reasons that we'll never fully know or understand. This could be filed under the kind of brain glitch that happens all the time to no ill effect or a near miss, but because it happened to someone flying a plane it was far more catastrophic.
Re: (Score:2)
But suicide doesn't actually require this level of motivation. At the moment the audio + actions suggest it was suicide.
Nationalists might actually prefer if it was a Jihadist or if they can somehow swing the proof of that.
Re: (Score:2)
> At the moment the audio + actions suggest it was suicide.
It's possible. In some cases, a suicidal act is an impulse. Which the subject regrets moments later (based in interviewing survivors of bridge jumping, etc).
It's also possible that this was an "Oh shit!" moment. The non-flying pilot "blocks" the throttles (thrust levers) during taxi to hold them in takeoff position (forward) with his hand. Once the plane rotates (nose wheel off the ground), that pilot removes his hand. The act of pulling a hand back could* put it in contact with the fuel switches. Which, l
There is new stuff, just not on Slashdot (Score:2)
There actually was some new information published since the last time the story was featured on Slashdot. Not surprised at the vacuous Slashdot reaction, however. Perhaps more significant that I don't feel like the quality of discussion on Slashdot these days merits the effort to dig up the link.
So as a memory exercise, I'll just summarize what I can recall. It was an article written by someone closely linked to the airline involved. Retired executive? Possibly also a former pilot? Quite familiar with norma
Re: (Score:2)
Only if you don't rule out your own islamaphobia.
Usually if a jihadist is in the middle of an act of terrorism on behalf of their beliefs, they aren't shy about letting people know it, or at the very least giving some kind of indication that they know they're going to die in the process and preparing for that in the moment.
There are absolutely zero indications of that, and absolutely nobody has claimed any kind of credit for this. And if it was a jihadist pilot, don't you think they'd also try to take some
Re: (Score:2)
Go fuck off with your islamaphobia.
What's your opinion on Jews?
Re: (Score:2)
I’m ok with them. Israel is another matter.