Air India Crash
- Thread starter Grim5
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My dad flew jets since the 80s and 787s for 5 year before he retired. I saw him tonight and just asked what his opinion was and he just came straight back with ‘fuel pumps weren’t on’. No idea if he’s right or not but I’ll just throw that one into the overclockers speculation pot
it didn't move, it stayed in the same place because it calculates it from the flap setting entered in the TAKEOFF page.
Haha, I changed one of the figures to make it easier to understand and forgot I had to change another to make them still add up
The FMC is all programmed correctly but I've not extended the flaps. As the speed increases, you see a config flaps error. No announcements.
What happens if you do set the flaps but do it wrong? Do you still get a warning?
From some videos shown of the wreckage by YouTubers the flaps are extended but at too low a level for takeoff, and they say that can't happen as a result of the crash?
Yes. If the flaps are not set the same as entered in the FMC, the warning is the same. It’s basically a flaps disagree.
I’ve said already that I think it’s flaps selected up instead of gear selected up after takeoff. That would have the same effect as what I tried, except it wouldn’t be instant.
Gear is raised so quickly after takeoff, I think the timings do work.
It's certainly a possibility but would that explain why the pilot reported losing engine power and thrust? Would losing flaps affect the engines like that?
Raising the flaps at that altitude and airspeed would be like shutting the engines off. The amount of lost lift would be unrecoverable. The plane lost lift and stalled and once they read the recorders we should hopefully find out why. Everything is really just a guess until then as there are so many variables.
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I was watching a video from Captain Steeeve last night where he was covering much of the same ground. He typically flies the 777 but apparently many of the FMC setup etc.. is the same with the 787 and he re-iterated many of the things already covered by you and others.
Namely that it's highly unlikely they either took off with incorrect flaps or no fuel as the FMC would be screaming warnings across the cockpit with Master Cautions flashing and alarms / claxons going off in the cockpit from the moment they put the power levers up to TOGA for take off.
He also mentioned the possibility of flaps being raised in error when the pilot would typically be calling for "gear up" at around 50ft or so off the ground and having achieved positive climb rate.
I personally just find it really difficult to believe that a trained First Officer (or a Captain acting as FO) would "mistakenly" sets Flaps 0, rather than raising the gear when called.
The 2 controls are rarely (if ever) located physically close to each other and typically the lever "handle" design is very different.
It just seems highly unlikely to me that such a fundamental basic error such as that would occur, It's not a task rarely handled or barely used, It's something they do routinely every single flight.
It would be akin to someone getting in their car one morning and instead of taking the handbrake off, they pop the boot release.
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That should have been a huge red flag. There's no way this plane should have been allowed to attempt a subsequent flight until these power issues were resolved.
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Soldato
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I was watching a video from Captain Steeeve last night where he was covering much of the same ground. He typically flies the 777 but apparently many of the FMC setup etc.. is the same with the 787 and he re-iterated many of the things already covered by you and others.
Namely that it's highly unlikely they either took off with incorrect flaps or no fuel as the FMC would be screaming warnings across the cockpit with Master Cautions flashing and alarms / claxons going off in the cockpit from the moment they put the power levers up to TOGA for take off.
He also mentioned the possibility of flaps being raised in error when the pilot would typically be calling for "gear up" at around 50ft or so off the ground and having achieved positive climb rate.
I personally just find it really difficult to believe that a trained First Officer (or a Captain acting as FO) would "mistakenly" sets Flaps 0, rather than raising the gear when called.
The 2 controls are rarely (if ever) located physically close to each other and typically the lever "handle" design is very different.
It just seems highly unlikely to me that such a fundamental basic error such as that would occur, It's not a task rarely handled or barely used, It's something they do routinely every single flight.
It would be akin to someone getting in their car one morning and instead of taking the handbrake off, they pop the boot release.
But it's not the same. It's more akin to every morning you take the handbrake off then a minute later pop the boot. But one morning, you're not really concentrating and you forget to take the handbrake off first and instead pop the boot. Seems very plausible to me.
No it wouldn't. It would be recoverable in seconds if the flaps were put back in their original place. Raising flaps by one notch doesn't reduce airspeed as it reduces drag.
I don't know how people are still running with the flaps ideas. You can hear the RAT, you can't hear the engines (hence the RAT out), supposed mayday call for "loss of thrust"... everything points to dual engine failure.
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I can’t say for certain on the 787, but other airliners I’ve worked on will run quite happily without the pumps on with mavity feed from the tanks, and I’d like think this sort of thing is shown during certification. The engine driven fuel pumps would be sucking the fuel in.
It also wouldn’t cause you to lose both engines at exactly the same time, and there would have been low pressure warnings given.
Sorry mate, but all this is academic. Electronic checklist on the 787 has a check for flaps as part of "Before Takeoff". That step can't be completed until the flaps are in the same position as entered into the FMC. Unless you're suggesting they didn't bother with the checklist which would also throw a warning on TOGA button.Two more screenshots from Aerowinx precision simulator, set up for a for a ten hour flight.
Again, this is a 744 but the principles can all be carried over to the Dreamliner (except the number of engines)
The FMC is all programmed correctly but I've not extended the flaps. As the speed increases, you see a config flaps error. No announcements.
I then hit TOGA, and rotated at V1.
Immediately at takeoff, the aircraft was pretty much in stall and there was no way the aircraft could build speed quickly enough to get above stall speed, even though I manually firewalled the thrust levers. I started gear retraction to reduce some drag but there wasn't enough time. I'm getting Pull up announcements and PULL UP is shown on the ND but the aircraft is dropping even though the nose is up. Only one thing will happen here.
The flight profile looks pretty much identical to the Air India one.
They took off with flaps.
If you really want to try an exercise in PSX, get loaded for a flight from Ahmedabad to London, you'll probably get a flaps 20 takeoff calculation. Take off with flaps 20. At gear up call, notch up to flaps 10. Do you die? What's the speed change on the stall warning markers on the speed tape?
Run the same again, but at gear up, select flaps up. Given how long it takes the flaps to retract, do you die?
But, and this is just a question, has the cockpit actually at that moment in time identified a literal loss of thrust. Or does the aircraft simply feel and behave like it has lost thrust.
To use this example if I am driving a car down the motorway and a passenger quietly and discreetly begins to engage the handbrake, the first sensation I would report is that I'm losing power - I'm unaware the brake is applied, so to me as the driver, my initial reaction is "I've got my foot down, the engine is labouring, but we're losing momentum, therefore the issue, as far as I can ascertain, is propulsion - I'm not expecting someone to have put the brakes on.
Obviously in a 787 I have a lot more instrumentation to warn me of the exact issue, but I'm wondering if it's a possibility. After all, plenty of air crashes have been lack or loss of situational awareness by crew who believe something is occurring when actually it's something totally different.
If the flaps started raising, it'd be felt like a growing sinking feeling, not a deceleration like with loss of thrust.
That pilot assessment earlier in the thread had stated you can’t see the front or rear flaps clear enough.
personally just find it really difficult to believe that a trained First Officer (or a Captain acting as FO) would "mistakenly" sets Flaps 0, rather than raising the gear when called.
The 2 controls are rarely (if ever) located physically close to each other and typically the lever "handle" design is very different.
It just seems highly unlikely to me that such a fundamental basic error such as that would occur, It's not a task rarely handled or barely used, It's something they do routinely every single flight.
It would be akin to someone getting in their car one morning and instead of taking the handbrake off, they pop the boot release.
History of aviation is littered with mistakes that are unlikely, unfathomable yet happened. The other scenario of dual engine failure is also highly unlikely, any outcome is highly unlikely that's how these things happen, the holes of the Swiss cheese line up to produce an unlikely outcome.
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If the engines have suddenly gone from take off thrust to nothing the feeling would be akin to hitting a wall by all accounts. They’d have felt that instantly, and the flight deck would suddenly light up like a Christmas tree with all sorts of warnings, especially when the generators tripped offline.
It would give them just enough time to get the mayday call out but that’s about it - pulling back to try to arrest the decent is about as much as they could do at that point.