Not suggesting fault on the part of the Pilot/s decision making, etc. However if we are interested in identifying near misses and improving outcomes, it should be investigated.
From the armchair, it looks like the aircraft entered an upset. That may have been due to incorrect technique in the application of rudder? Standards should be improved in many operations in hand flying and best practice. Thats apart from Pilots taking undue risks as a result of lack of awareness, poor training or commercial pressure |
Can these changing conditions be reproduced in the Sim?
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Dogma, what is there to investigate, and to what purpose?
The debate would be on a point of judgement; a continued landing in the same circumstances may have involved higher risk, so the appropriate ‘bounced recovery’ and GA was the better option. Yet a small change in the wind gust or a few seconds of flight path would present a completely different situation. Is it possible to predict that; I doubt it. (Hence you cannot simulate the appropriate level of fidelity G-CPTN) How can you improve the outcome of a correctly executed procedure; can you better manage the risk, etc. Celebrate the success, reinforce the choice of a GA in similar situations. If you wish to judge the choice in commencing the approach then you must consider the view of the Captain, the information available, at that time, skill, qualification and the many other variables. The human is usually very good at this type of judgement, superior to automation; and yet the same human is particularly bad in judging events after the fact, generating wild conclusions based on hindsight and constructing ‘error’, whereas the behaviour was as required for the situation. Armchair views may be the greater risk to the safety in industry because they may covertly influence crews towards courses of action to mitigate media reaction vice managing the risks in flying. You cannot conclude a ridiculous view of an upset, or inappropriate use of control; you were not there, did not have the same perception as the crew, or experience in judging situations. You must start with the view that the crew choice and actions were as required; the crew were doing their best in the conditons, which from the video appeared to be by the book. Well done that crew. |
Textbook stuff from someone on top of their game.
Well done chaps (or chapesses):ok: |
Having been encouraged to post in other than Jet Blast, I will opine here on this after doing a little (not a lot) of research composed of watching the three vids avail, and gathering the weather for the location at the time. Being a high time private/comm pilot, with a flight history in windy areas like N TX, and eastern CO, this is my take.
Based on the underside look of those clouds, along with the clear evidence in the background of the vid, there is moist unstable air in the area at the time of the appr. Combine this with the reported wind of 270@26G46 also indicates that the wind conditions were quite dramatic when the gust is 20 up from the sustained, and the sustained is rather high as well. Having flown much of my time in TW aircraft(yes, I know - has nothing to do with airliners) we have been taught the cross-controlled appr with upwind wing low, and opposite rudder. Airline operators apparently either HATE this method, or they are untrained, or the company doesn't allow it because it tilts the SLF in an awkward way, hanging as they would be from the side of their belts. Understandable. In my little cloth plane, in these conditions, I would have been fully cross controlled, and trying to touch the right main and stick it on. More than likely after having stuck said right tire to the ground I would realize the folly of winding up in the grass, or a ditch, and power my way out of there and go somewhere else. Airliner? The kick-out method is accepted process, and damn the side-loading of the gear. Can it be done cleanly with min side loading? Sure, in fairly smooth sustained wind. But in conditions with G46? Oh he-ull no. In Brit-speak I would say this would be a rather 'sporting' attempt. No fault, no foul, no issue with what I see here having the guys in the pointy end getting out of Dodge(Americanism from the old west) nee Salzburg and heading somewhere else. The meatsacks all walked off the plane, the plane apparently can be used again, and if there is an inquiry, and I were in the pointy end I would simply say that conditions were beyond SAFE margin when WE made our attempt, notwithstanding any previous, or later landings. It was a semi-unstabilized approach, leading to a unstabilized flare, leading to an unstabilized touchdown, and we performed a textbook go around. Have a nice day. Skin, tin, ticket all secured, sadly the cabin creatures had to make other arrangements, but somedays one is the bug, and somedays one is the windscreen. |
We must also consider the experience of the crew, Pilots who regularly fly into "interesting" locations will cope with these conditions rather better than those from the parts of the world where landings are almost always benign.
Personally I would probably have thrown it away a bit earlier but wibble flip, I was not there on the day. |
I love it when a simple TOGA creates such an in-depth and irrelevant discussion and debate. Being a dinosaur I keep shtum for most of the time, but I'd like to know just what vertical g was registered upon impact. I have run the link many, many times, and still the groundspeed shrieks out at me. Not having that kinetic energy in the bank is asking for . . . well, what they got. I'm surprised by the reported wind angle, but if the wind was fairly consistent from the west and the runway was 33, then a sudden gust from 20 to mid forties does create a demanding challenge, but not one that allows the shadowed starboard wing to be bullied by the added ground-lift under the port wing. That should have been fully anticipated. I have a bad feeling the close monitoring of pilot's actions - in almost any unusual scenario these days - is becoming a very counterproductive routine. I picked the word routine with some care. I suppose these days even a tad of crossing up to counter the crosswind would be considered a cardinal sin. I rather think the SLF would prefer a touch of 'side' to being subject to that kind of thumper. |
Originally Posted by SFCC
(Post 9942524)
Textbook stuff from someone on top of their game.
Well done chaps (or chapesses):ok: That was a save! They were not far away from a pod or wingtip strike (which ever hits first) |
I am surprised that no one has pointed out that 33 is a fairly unusual runway. We always use it in the sim, because it is a tricky approach (not as tricky as it used to be when only a circling was published ). At least for us it needs to be demonstrated in the box as a cat c airport, captains only landing. However in real life over many years I have never flown it, the ILS the other end has always been in use. The only plus side is that the missed approach is a lot easier than off the ILS, which again is always practised in the sim.
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Watch the video with the audio turned up. A fair amount of wing flex, and audible interior creaking, indicates it was a rough day.
I'm not sure I've every heard that much interior creaking due to turbulence before. It was a challenging approach. |
On the NG, Flap 30 gives significantly better handling in strong crosswinds than Flap 40. The FCTM says sideslip only landings should not be attempted in crosswinds above 18kts with Flap 30 due to lack of control authority and pod strike risks.
Someone with a camera on DUB 16 in similar winds would probably get some pretty exciting footage too. |
Wind 270/26G46 gives a gustiness factor of 77% which is quite high - then add the local topography.
Gustiness factor |
From the video of the wing from inside the plane the touchdown was not that hard, which suggests he had decided to go around well before it 'landed'.
SLF, but I've been in planes that landed with no drama when the wing was working much harder than that on the approach - and enjoyed the marriage of engineering and art that makes it possible. I thought that a late go-around could result in a touch and go simply because it takes time for the engines to spool up and develop thrust? |
On most jet transports you can go around up to the point when reverse thrust is selected - so the wheel(s) could be on the ground before initiating a go around.
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Originally Posted by EGPFlyer
(Post 9942384)
On the A320, reduced flap (3) is recommended for windshear
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Those winds are the trickier approach onto 33 make for an interesting day out.
Did anyone else think the Ground Speed looked pretty high from the videos? |
What! In excess of walking speed you mean? Okay, I'm being sarcastic, but GS high?
The FCTM says sideslip only landings should not be attempted in crosswinds above 18kts with Flap 30 due to lack of control authority and pod strike risks. |
It seems GS high.
See an external video from other guy filming in HD: https://www.youtube.com/watch?v=zbUbI9ufDiM |
Certainly, there's a moment when they are still over the grass when it looks alarmingly like it is being accelerated by a TWC, (dangerous in its own right) but when the viewpoint is as the OP, then I still think there's insufficient kinetic energy to give safe reserves.
It really does need recorded data to be sure, though I don't know if this is one of the parameters directly sensed or even deducible. |
excellent video of the challenging APP and conditions of the day
looks like the field was right on the edge of a major downpour |
If you look at 1.50-1.55mins, as the a/c goes into a severe right wing down (downwind), you'll notice the left aileron UP accompanied by the flight spoilers. This suggests a large left aileron input, yet the a/c goes into sharp right bank. That would suggest some large right rudder input to remove the drift accompanied by left aileron to counteract the associated roll. Except, either SOD's law was in action and a gust from the left got under the wing, or the rudder input was too agricultural and over-rode the aileron input. We know that at lower speeds the rudder can be more powerful than aileron and needs finesse. Why the a/c then suddenly lunged onto the left wheel is speculation; either the gust was removed or the size 12 on the rudder relaxed and the a/c came under aileron control in rapid fashion.
The GA was an excellent decision and well executed. As in Question of Sport (and it did look sporting) is 'what happened next?' It looked do-able for a 2nd attempt. |
Loose rivets - the NG has poor pod clearance (better than a jumbo though) and will strike a pod at 15° in the landing attitude.
Boeing have obviously tested these conditions and the have decided the margin against podstrike is not enough in those wind conditions. The massively over -developed NG is assuredly not an early jet transport and if one had a pod strike ignoring the FCTM advice a meeting would surely follow even at more enlightened airlines. |
they went back to FRA and did not have another go
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Well, no one came blame the crew for deciding that was enough for today and head back to Frankfurt. Can they?
With so many of these videos on you tube often sensationalised it would be nice if the media occasionally mentioned how well the plane is protected from serious harm by the awesome power , and it is awesome power even on a 737 that can shove the aircraft up and away from danger. In fact as we have seen to some extent the greatest danger sometimes is not being able to control the aircraft as it powers away from the ground. The media cannot seem to get their head around that what really was a risky business in a piston prop or early jet with a horrid spool up lag is a far far less dangerous situation today |
JW, yes but 15 degrees would be a dramatic angle, while up to 5 degrees, even 7, might just have saved that right wing dropping - given that it had that extra speed to support the manoeuvre. One would have to be very mindful that a 60 degree crosswind might suddenly become a tail wind and speed an embarrassment. Also, I'm making the assumption that other techniques might obviate such severe compression of the gear, and all that goes with that.
Yes, it's all very different to the old days, though we had to be mindful of flaps. It occurs to me that what happened here could be as a direct result of manufacturer's strangling mandates based on early testing. Days like this one are the real world and demands on the crew might well make dramatic departures from testing envelope limits. I must make it quite clear, my prime argument is about the strangulation of crew abilities because of hard and fast rules. I've mentioned recently being thrown sideways over some buildings at about 100' during a Palma takeoff. There was zero on one ASI, and 350kts on the other. I doubt there had ever been the feedback to cover such a bizarre split from current teaching. Anyway, until there is a definitive log of the ground-speed, any thoughts I have about that issue are little more than guesswork. |
Gusts take many 3-dimensional forms and, most inconveniently for pilots, don't stay put - plus you can't see them. In fact they could be characterised as 4-dimensional forms.
It's like whitewater canoeing with a blindfold and ear muffs. You don't know what it is until you are in its teeth. Once you have been nibbled on by one of these beasts, your tolerance of the peanut gallery will be limited. |
what is the spool up time from approach idle to an appreciable fraction of toga thrust?
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About 8 seconds max.
Part 25 limits the time from flight idle to go around thrust to 8 seconds |
I think we're talking "approach idle" here, says the SLF sitting on his couch with Google. I'm trying to understand how many seconds of ground-effect hell the pilots need to endure in such a situation before the TOGA spoolup lifts them away. This is when the decision not to land has already been made. That's the duration when they are basically sitting ducks for crosswind gusts, forced to stay vaguely above the runway and stuck close to the tarmac in altitude.
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Originally Posted by edmundronald
(Post 9945023)
I That's the duration when they are basically sitting ducks for crosswind gusts, forced to stay vaguely above the runway and stuck close to the tarmac in altitude.
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What a fuss over a normal approach and well executed go around. Not even the cameraman could keep his camera steady. In the 2 minute video, while crosswind in the approach, there seems to be heavy rainfall behind him with the risk of it creating a tailwind in the last phase of final. And look at the trees how they were lashing back and forth. There was a good ceiling and visibility, they flew the crosswind and final approach in turbulent but visual conditions, and perhaps but for the last gust during the flare it would have been a good landing. The GA was a perfect decision, instead of trying to fix a bounced landing. And re the comment of some making it in and others diverting, the conditiions in that sort of weather and can and do vary inmensely from minute to minute. Well done to the crew.
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I think we're talking "approach idle" here, says the SLF sitting on his couch with Google. I'm trying to understand how many seconds of ground-effect hell the pilots need to endure in such a situation before the TOGA spoolup lifts them away. He went on to say: This is when the decision not to land has already been made. That's the duration when they are basically sitting ducks for crosswind gusts, forced to stay vaguely above the runway and stuck close to the tarmac in altitude. A reply from FIRESYSOK: Seriously? You think we are taught to ‘milk it’ until one or both wings stall or engines spool up, whichever occurs first? 4djd9 What a fuss over a normal approach and well executed go around. I accept I'm beating an old drum while in a new science. I'd be reasonably confident on that day in an aircraft with conventional controls but telling a computer how to input to the flight surfaces is perhaps something I should bow out from. I'll read in with continued interest. |
Originally Posted by 4djd9
(Post 9945678)
What a fuss over a normal approach and well executed go around. Not even the cameraman could keep his camera steady. In the 2 minute video, while crosswind in the approach, there seems to be heavy rainfall behind him with the risk of it creating a tailwind in the last phase of final. And look at the trees how they were lashing back and forth. There was a good ceiling and visibility, they flew the crosswind and final approach in turbulent but visual conditions, and perhaps but for the last gust during the flare it would have been a good landing. The GA was a perfect decision, instead of trying to fix a bounced landing. And re the comment of some making it in and others diverting, the conditiions in that sort of weather and can and do vary inmensely from minute to minute. Well done to the crew.
Due to the greater chance of a tip strike due to the scimitar winglets the crab to touchdown technique will be mandated. Every jet I've flown, from 737 to A320 to 767 I have kicked out the crab starting in the flare and touched down with one wing slightly low, to prevent side gear loading. I've seen the videos of the 380s landing crabbed and the guys I fly with that flew B52s say they land that way all the time. These guys did a good job with the conditions they were in. They did a great job not trying to save the bounce. Going around and diverting was the best move. |
I accept I'm beating an old drum while in a new science. I'd be reasonably confident on that day in an aircraft with conventional controls but telling a computer how to input to the flight surfaces is perhaps something I should bow out from. I'll read in with continued interest. |
Thank you for your generosity.
I'm sure the pilots handled a situation well within parameters with a standard procedure that was well executed - I am just trying to understand it. As an SLF armed only with Google and Mark I brain, I'm trying to figure out from basic physics how trained professionals fly me from A to B repeatably and safely. They come down to close zero altitude above hard pavement at "approach idle" thrust with little energy and DECIDE conditions are not conducive to wheels down. The pilots hit the TOGA thrust buttons, but then have to fly the aircraft attitude themselves, with hands and brains, not computer. The wind is gusting unpredictably. My naive guess is that in still air they could rotate away 1-2 seconds after TOGA, trade some of their remaining airspeed for a few feet of altitude, and quickly get a kick in the seat from the engine spool up and be away. But here they cannot risk rotating up precisely because as FIRESYSOK says if they slow down, an unpredictable tailwind gust could stall one or both wings while they are just above the tarmac- so they need to keep airspeed, which can now be very different from groundspeed. So they are trapped in crosswind hell, fairly near the ground, for a longer time, something like 4-6 seconds, the thrust lag making it more risky to try to go up than to stay level, even with TOGA already set. After 4 seconds or so, they rotate and the engines take them away. I'm sure someone with real knowledge will be happy to explain the errors in my understanding. One thing I do understand is that this is a case where the guys sitting in the seats in front of first class are earning their pay. |
You are missing a lot of information.No one lands at idle in that situation. You don't pull the thrust levers On a normal approach back to idle until you are within 20 feet. When you are making a crosswind landing there is power on until close (really close) proximity to the runway. No 'chop and plop".That is why the flap setting on approach is critical. Flaps out provides drag at landing flap settings, necessitating thrust on the engine to maintain approach speed. On the 757 that would be about 3000#/hr per side (I use EPR on the RB211 - landing weight in Thousands of pounds mover two decimal points over, I.e. 185k pound landing weight would have 1.18 EPR for a ballpark power setting)
You can't go around like they did from a dead idle. They had the engines still spooled and hitting the go around switch resulted in instant power. Someone else pointed out the lack of spoiler deployment. That's because the TLs were up and not at idle. Don't over analyze this. It was a crappy day and they did their jobs. |
Originally Posted by cactusbusdrvr
(Post 9946831)
You are missing a lot of information.No one lands at idle in that situation. You don't pull the thrust levers On a normal approach back to idle until you are within 20 feet. When you are making a crosswind landing there is power on until close (really close) proximity to the runway. No 'chop and plop".
...which is true, and what you said ("within 20 feet") is consistent with that, so I don't see where the disagreement is. Incidentally, my airplane specifies idle and Vref at 50 feet, with no deviation for crosswinds or gusts. You're speaking in absolutes that aren't true. |
What airline and what jet do you fly? I've never pulled power at 50' gear above the pavement . And flying Vref in a gusty wind like that is a recipe for a tailstrike on a long jet like an A321 ORD a 757.
There is no way they were at idle on that approach. |
CRJ at an American regional. The particular procedures for your plane/airline can not substantiate your absolute statements that "no one" lands at idle in that situation, or that even on a normal approach you don't pull to idle until 20 feet.
Edmundronald actually has demonstrated a very good grasp of the problem/situation, which is that the spool up lag of a jet creates a vulnerable time gap between setting idle power and touching down, during which you cannot climb and might very well be committed to touching down even after a go-around decision has been made, and power applied. That somebody's procedures for a gusty crosswind would call for a later pull to idle so as to shrink this time gap and mitigate the problem, is a confirmation of his reasoning and not a refutation. But what I see is not reasoned responses to his posts, but instead people looking to make the most obtuse, willful misinterpretations of them, so as to conjure up justification to jump down his throat for having the temerity to post where only the vaunted professionals are allowed. |
Originally Posted by Vessbot
(Post 9946864)
CRJ at an American regional. The particular procedures for your plane/airline can not substantiate your absolute statements that "no one" lands at idle in that situation, or that even on a normal approach you don't pull to idle until 20 feet.
Edmundronald actually has demonstrated a very good grasp of the problem/situation, which is that the spool up lag of a jet creates a vulnerable time gap between setting idle power and touching down, during which you cannot climb and might very well be committed to touching down even after a go-around decision has been made, and power applied. That somebody's procedures for a gusty crosswind would call for a later pull to idle so as to shrink this time gap and mitigate the problem, is a confirmation of his reasoning and not a refutation. But what I see is not reasoned responses to his posts, but instead people looking to make the most obtuse, willful misinterpretations of them, so as to conjure up justification to jump down his throat for having the temerity to post where only the vaunted professionals are allowed. I don't want to beat this into a dead horse, but..... When you do a Cat3 approach in the sim what happens when you get a failure inside of 100'? You go around, right? In a large jet, or even a RJ, you will get contact with the runway if the go around is triggered at a low enough altitude. But you are committed to the go, you never, never attempt to land after the go around is initiated. The power comes up from the approach power setting and off you go. I've done a hundred of them, the sim IPs just love to do the "no flare" failure. Or the proverbial "truck on the runway, go around". I can assure you that if you ever try to abort a go around once you have hit the TOGA switch you will get a bust for that maneuver. The only time you would reject out of a go around is if you totally cocked it up and stayed on the ground long enough to trigger the spoilers or you had selected reveres thrust. The Air/ground switch switches to landed mode after about 3 seconds (sorry, that's off the top of my head). So you have a second or two on the runway to allow for thrust to fully come up if ground contact was made. I am sure that these guys were spring loaded to do a go around if things did not work out, which is what transpired. When that wing dipped in the gust there were probably two hands ready to push up the levers. You can just tell by how quickly it climbed that the engines were up enough to quickly reach go around thrust. |
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