Best video I've seen of it yet, from the car behind the Taxi in the link above.
Troubleshot wrote:Just curious for a pilots thoughts on why the aircraft could not maintain flight after an apparent engine failure? I thought transport cat. aircraft are certified to that level of safety.
I understand there could have been (and likely) several variables that lead to the crash but just a "black and white" view, should that aircraft been able to climb to a safe altitude? I'm not asking for the cause, just the performance numbers. On paper that plane should be able to maintain flight with a flame out....correct or no?
thanks
Yes they are, but that is predicated on systems operating as designed (ie Autofeather and or alternate feather), and proficient pilot skill. Any number of reasons why it got to this point- I'm reasonably sure by the videos that it stalled. The question is why? Flap retraction initiated below V_fri? Wrong engine identified during the 'drill'? #1 engine not fully feathered? Improper control inputs by the PF?
I'm a Q400/DH8 guy, but as I understand it, the ATR600 does not have excessive power like the Q (similar size aircraft/capacities). Regardless of the power available when an engine fails after V1, improper control inputs will make your job of climbing away hellish. I have seen many times in the sim where a pilot will ignore basic twin-engine piloting technique with an engine failed, and try to climb out with too much rudder input which invariably leads to (trying) to climb out in a cross-controlled type scenario. The VSI hovers around 50-100 FPM, perhaps the stick shaker activates, the EGPWS starts yelling about not sinking- it can get ugly. The advantage I have at that point is to hit flight-freeze, point out some observations from my seat, reposition to the threshold and say "let's try that again".
I'm not saying that's necessarily what I think happened here, but if all the systems operated normally, the aircraft was within its CofG and weight limits, and it was a simple "flame out" (words from flight), then the next probability would be a pilot issue.
This flight apparently made it to 1000' or more, which leads me to think they obviously did things right to that point. Next would be cleaning up the mess (accelerate, flap retract, shutdown drill etc.). It would seem that maybe this is where things went sideways.
Just my opinion.
Thanks that's all I was looking for, the "on-paper" capabilities of single engine performance on a turbo prop that size. Like you say, seems like more to the story than just power. Have to wait and see.
Does aileron position really matter at that point, though? It can't be helping matters, but the damage to stable flight was done several seconds previously, so I think they were stuffed in any case..
Will increase the roll rate into the spin substantially, possibly many 10s of degrees per second above and beyond what was already happening. Does that matter.. may have saved a few more lives.
A number of years ago we lost the #1 just after rotation departing Sault St Marie. It was on the ATR 42-300. Autofeather and uptrim worked liked it was supposed to and the aircraft flew quite nice as it should.
Looking at the video from behind the taxi -- to me it appears that the aircraft had stalled even before it comes into clear view in the video -- will be interesting to see crew experience levels -- with a short flight he should be well under max gross unless they were tankering fuel. Interesting also that they were able xmit a mayday -- why would they take time to do that -- means to me someone was not doing their job or had given up long before he should have --------
Liquid Charlie wrote:Looking at the video from behind the taxi -- to me it appears that the aircraft had stalled even before it comes into clear view in the video -- will be interesting to see crew experience levels -- with a short flight he should be well under max gross unless they were tankering fuel. Interesting also that they were able xmit a mayday -- why would they take time to do that -- means to me someone was not doing their job or had given up long before he should have --------
Or perhaps they had the situation under control until something else occurred. I believe I read somewhere that the Captain had over 4k hours.
The pilot flying had accumulated 4,914 flight hours and his co-pilot, 6,922 flight hours, says Lin. There was also a third pilot in the jump seat with over 16,000 flight hours of experience.
Napoleon So Low wrote:The pilot flying had accumulated 4,914 flight hours and his co-pilot, 6,922 flight hours, says Lin. There was also a third pilot in the jump seat with over 16,000 flight hours of experience.
Our ATR 42 SOP's had us turn the autofeather off at top of the second segment and this aircraft actually made it a little bit from the airport when the issue happened. So just thinking out loud here...........it appears the #1 is feathered but maybe the #1 was not the engine that failed. It may have been the #2 that failed and it did not autofeather and the crew feathered the good engine. CRV/FDR should answer this pretty quick.
However........it does appear that the #2 is still rotating. Lets wait for the report I guess.
Napoleon So Low wrote:Media reports (National Post) now praising the crew as heroes.
They were aiming for the river to save lives on the ground. So says a Taiwanese aviation expert.
I predict the crew was busy trying to keep the blue side up and get the altimeter going up. I don't think they had much control about where they were going, or how they 'knife-edged' through the lamp-standards on their way into to the river...
So I'm no pilot, just an Ame....... When you look at the extended video, that bad boy was pancaking pretty good for quite a while before the crash. The sick shakers would be going mad and the stick pusher would also be coming into action.... Would they not? I'm only assuming here.
At the altitude and speed depicted in the video, would it even be possible to come out of that? I guess it is possible that in order to recover, they would have had to fly through high rise buildings.
Looks like it stalled at the top of the second segment climb and held it there. Radar data shows a speed decay down to about 75knots GS correlating with the initial decent. Looks like they held it there up until impact. The stall speed clean on this thing is 105 knots and the Vso is 88 knots at MTOW. Pure speculation however.
ourkid2000 wrote:So I'm no pilot, just an Ame....... When you look at the extended video, that bad boy was pancaking pretty good for quite a while before the crash. The sick shakers would be going mad and the stick pusher would also be coming into action.... Would they not? I'm only assuming here.
At the altitude and speed depicted in the video, would it even be possible to come out of that? I guess it is possible that in order to recover, they would have had to fly through high rise buildings.
Sounds to me like your assumption is pretty much correct.
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ourkid2000 wrote:I guess it is possible that in order to recover, they would have had to fly through high rise buildings.
If you look at the track, it looks as if they flew a fair distance back and forth over the river on one engine at the edge of the stall. So they could have pushed the nose down and flown low over the river, which would have probably given them enough speed, or failing that they could have put it down in the river.
My guess is that they let the speed decay too much and then their instinct was to hold the thing in the air, and by the time they got to those buildings they were out of options.
ourkid2000 wrote:So I'm no pilot, just an Ame....... When you look at the extended video, that bad boy was pancaking pretty good for quite a while before the crash. The sick shakers would be going mad and the stick pusher would also be coming into action.... Would they not? I'm only assuming here.
At the altitude and speed depicted in the video, would it even be possible to come out of that? I guess it is possible that in order to recover, they would have had to fly through high rise buildings.
Shakers for sure. Not sure if it's equipped with a pusher-system (usually dependant on the stall characteristics during design/flight test), but if it has one, it's likely inhibited below an altitude off the radalt, say maybe 400'. Pusher systems are complex systems with regards to when they push. They have a myriad of inputs and processing that determines when to activate. Just because it's stalled, doesn't mean a push will occur.
