A loud bang described could be the deployment of the RAT. The thing is the size of a Cessna propeller.
This is a landing during delivery/test with the RAT deployed - you can hear it clearly too but not from the rear:
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Air India Crash
- Thread starter Grim5
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A loud bang described could be the deployment of the RAT. The thing is the size of a Cessna propeller.
This is a landing during delivery/test with the RAT deployed - you can hear it clearly too but not from the rear:
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There isn’t enough time. Of the 23 second flight, gear selection would be maybe 5 second into it. Flap travel takes a while, and there wouldn’t have been long enough to make the amount of difference the aircraft suffered before stalling.
Winner I reckon. Most likely a case of action slip of retracting flaps one stage instead of gear up, and at a heavy weight and high temp as here, back down she goes unfortunately.
The only issue with this is the RAT deploying. Which if true, would indicate some kind of major failure.
Also, if the aircraft was almost stalling due to inadvertent flap retraction (I believe the 787 FBW system will not allow you to pitch to a stall), I would expect the pilots to instinctively add thrust (to maximum if possible). You would hear that in the video I think. Also, if it’s anything like the 737, it’s actually quite hard to fully retract the flaps as there is a gate at flaps 1.
But to me it looks like either that or some kind of bizarre dual engine failure.
Isn't enough time for what? Flaps/slats coming in will only take a few seconds.
I'm not sure there has been any conclusive proof of that
Absolutely conclusive, no. But there is an extremely RAT-like noise heard at the beginning of the video, and it does not sound like two GENx engines on full thrust either.
Dropping a single flap setting with two working engines is still possible to be recovered from - it's not an automatic stall. Dropping the nose to try and maintain level flight could allow for some acceleration.
Doesnt explain why (if ) the RAT was deployed.
Thats the same aircraft departing Sydney. 6 seconds after rotation the gear up is commanded, with a further 13 seconds to stow.
Almost the entire flight time of the fatal flight. So if they had an engine failure at or just after V1, >> Aviate, Navigate, Communicate. The cockpit got very very busy so gear up is not important at that time
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I only fly light aircraft and have no idea about jets but when you feel the stall coming you have it drummed into you full power and nose down attitude. It is basically second nature for me now. Not that I get close to stall speed as I make sure I am doing a decent rate of knots before rotation! I don't understand where this pull up mentality comes from unless it is something that wasn't taught "back in the day".
Although I guess when you have big powerful jets you just forget about principles of flight and just power out of it!
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If you have altitude to play with, you can recover. With a few hundred feet, you have few (if any) options that'll work.
Yup, it’s essential to reducing drag and getting in the air. Even with a single engine failure at takeoff, you’re getting the aircraft cleaned up as quickly as possible.
If the engines failed wouldn't it have dropped the RAT?
*EDIT*
This was posted three hours ago, signal must have been poor.
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Supposedly automatically dropped for two reasons - primary and aux power fails, and the second reason is the hydraulic pressure drops.
Caporegime
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Yeah in my early days I was doing a touch and go and put my flaps up too quickly. That was a fun experience and taught me a valid lesson in decreased lift but was still able to get my nose down and get airspeed back up to climb. In a heavy jet it is most likely game over at just 400 feet as everything is just multiplied by a massive magnitude.
Agreed. And even if it wasn't recoverable you would see the descent rate start at least to shallow out if engine power was increased. I've had an actual stall warning in flight shortly after take-off (it was a sensor failure, not me being an idiot). Before I even had time to think I'd dropped the nose to the horizon and added a bootfull of power - it should be instinctive, and I have no reason to believe these pilots would be any different.
The only issue with big jets is the pitch power couple of the engines mounted below the wings (and below the CoG) - as you increase power, the nose of the aircraft rises. If you've stalled with a nose high attitude, increasing to power can just cause the nose to rise even higher making the situation worse. So initially you need to get the nose down, with elevator (and rudder, if it's really bad) before applying power. None of which will work if you are just above the ground. That being said - in this case with a relative low pitch, I would expect that not to be an issue.
I don't think this was a single engine failure - you would see the aircraft yaw and a wing drop towards the failed engine before aileron and rudder are applied to correct for it. And the aircraft would still fly, and although I'm guessing here, I would think there's probably enough wriggle room in the performance calculations that the aircraft would still fly even if the gear was not up. Even if I'm wrong about that I don't think it would fall out the sky so quickly.
(I've done it in the sim in a B737, the aircraft still climbs, just very slowly)
If both engines fail it doesn't matter what you do with the gear. Loss of hydraulics means the gear wouldn't come up anyway even if you tried.
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