Control column flailing during the flare - a dangerous practice by some pilots.
Vessbot No, I mean he is not even crabbing just making rudder displacement that looks like crabbing but in crabbing you don't use the rudder to crab and also his 'Recovery procedure i.e. a late "decrab" resulted in PIOs
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I don't follow. First you said he didn't crab, which is incorrect seeing as he was clearly in a crab before landing.
Then you said that he is "making rudder displacements that look like crabbing" but in the same sentence note (correctly, but in contradiction with the prior part) that you don't use rudder to crab.
Lastly you say that "he holds the rudder so that the nose is into the wind" but there is no rudder needed (or applied in the video) to hold the nose into the wind. Nose into the wind, aka a crab, is the default state when the wings are level and the ball is in the middle.
It takes rudder to move the nose away from the wind and toward the centerline (aka decrab, aka slip). Maybe by "hold" you meant "no displacement," but that is what a crab is, which you maintain he didn't do.
We've agreed that he decrabbed incorrectly (by doing it too late) but what is incorrect about the crabbing?
Then you said that he is "making rudder displacements that look like crabbing" but in the same sentence note (correctly, but in contradiction with the prior part) that you don't use rudder to crab.
Lastly you say that "he holds the rudder so that the nose is into the wind" but there is no rudder needed (or applied in the video) to hold the nose into the wind. Nose into the wind, aka a crab, is the default state when the wings are level and the ball is in the middle.
It takes rudder to move the nose away from the wind and toward the centerline (aka decrab, aka slip). Maybe by "hold" you meant "no displacement," but that is what a crab is, which you maintain he didn't do.
We've agreed that he decrabbed incorrectly (by doing it too late) but what is incorrect about the crabbing?
He's using the rudder back and forth to crab instead of making a coordinated turn and neutralizing all control surface except for tiny movements of the ailerons or at worst the spoilers too in order to accomadate for gusts
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"rudder back and forth to crab" 
The conditions are turbulent, which requires rudder to stabilize yaw. (Some amount coming from the pedals, some from the yaw damp; how much of each, who knows) What does this have to do with the crab?
[crab] "instead of making a ... turn" These things can't be instead of each other. They are necessarily two separate phases of the landing, regardless of any technique variation. The turn is the termination of the crab, and the initiation of alignment of the nose to the centerline
"movements of the ailerons ... to accommodate for gusts" that cause roll deviations. What does this have to do with the rudder?
The conditions are turbulent, which requires rudder to stabilize yaw. (Some amount coming from the pedals, some from the yaw damp; how much of each, who knows) What does this have to do with the crab?[crab] "instead of making a ... turn" These things can't be instead of each other. They are necessarily two separate phases of the landing, regardless of any technique variation. The turn is the termination of the crab, and the initiation of alignment of the nose to the centerline
"movements of the ailerons ... to accommodate for gusts" that cause roll deviations. What does this have to do with the rudder?
Actually there's no need to decrab....that didn't look like YD inputs to me.. I believe that that PF was trying to crab with the rudder at least that's what it looked like to me.
Gentlemen, please.
One can adjust one’s crab angle with the rudder - incorrect technique while airborne , but it can be done. After all, that’s how you do it when de-crabbing.
Maybe the PF wanted to keep the wings level to avoid a pod strike but wanted to adjust the crab angle?
One can adjust one’s crab angle with the rudder - incorrect technique while airborne , but it can be done. After all, that’s how you do it when de-crabbing.
Maybe the PF wanted to keep the wings level to avoid a pod strike but wanted to adjust the crab angle?
Uplinker then this video illustrates what improper technique could lead..and I used to feel a little bad about using the rudder to push of the crab to fly runway HDG but I did
Yes and so you should, keeping the into wind wing slightly down. Slip into wind. If the into wind wing is slightly raised from level, then you may expect a pod strike on the DW wing. Re: A320 DUS,Germany. D/W wingtip strike.
If you de crab at the last second, or don't attempt to, the main wheels then nose wheels may not contact the concrete, where you want them. I.E., on the C/L. Correct me if I'm wrong, if you aim to land on the C/L but don't, then you don't have full control of the A/C, or do you?
I prefer to gently and gradually begin to cross the controls early. Say 200 to 300 ft gal.at least. I've seen it done, by past masters of early 4 underslung eng, jets. At "max demonstrated" with no side loading on the U/G at touch down. The time and place to hone these skills is on tailwheel aircraft or aircraft on floats. Tailwheel, C of G behind the main wheels and floats, when they hit the water, you're on rails. You go where the floats are pointing.
I am well aware the book and a lot companies don't encourage the above. You have to get it right. However I can't think of anything worse, sitting in an a/c, or watching someone not attempting to decrab and hitting the R/W at high drift angles. The tyre companies love it and so do the A/C manufacturers of course.
If you de crab at the last second, or don't attempt to, the main wheels then nose wheels may not contact the concrete, where you want them. I.E., on the C/L. Correct me if I'm wrong, if you aim to land on the C/L but don't, then you don't have full control of the A/C, or do you?
I prefer to gently and gradually begin to cross the controls early. Say 200 to 300 ft gal.at least. I've seen it done, by past masters of early 4 underslung eng, jets. At "max demonstrated" with no side loading on the U/G at touch down. The time and place to hone these skills is on tailwheel aircraft or aircraft on floats. Tailwheel, C of G behind the main wheels and floats, when they hit the water, you're on rails. You go where the floats are pointing.
I am well aware the book and a lot companies don't encourage the above. You have to get it right. However I can't think of anything worse, sitting in an a/c, or watching someone not attempting to decrab and hitting the R/W at high drift angles. The tyre companies love it and so do the A/C manufacturers of course.
Last edited by Dan_Brown; 25th Aug 2018 at 19:05.
Below the Glidepath - not correcting
Unsurprisingly this is also a characteristic of low-hour rotary pilots when hovering. The cyclic is whipping around the cockpit like something from a cooking lesson, rather than a flying lesson. Eventually, they begin to understand that rapid application of left cyclic followed immediately by right cyclic equals exactly zero, and as confidence grows, they begin to calm down. The other parallel with these videos and comments is when on more advanced helicopters the auto stabilization was deselected, most pilots reverted to stick-stirring, but pilots who had more hours on manual only control systems instinctively understood that less control inputs made for smoother flight.
It all comes down to understanding primary and secondary effects of controls, understanding input lag and aerodynamic reaction times, and ultimately understanding that inertia is your friend, not your enemy. Plan early, plan often. Experience is almost certainly a factor of confidence, and unfortunately if flying with the autos disconnected is rarely practiced, it's hardly surprising experience and confidence levels suffer.
Sometimes it's just better not to know what's going on the other side of that door.
It all comes down to understanding primary and secondary effects of controls, understanding input lag and aerodynamic reaction times, and ultimately understanding that inertia is your friend, not your enemy. Plan early, plan often. Experience is almost certainly a factor of confidence, and unfortunately if flying with the autos disconnected is rarely practiced, it's hardly surprising experience and confidence levels suffer.
Sometimes it's just better not to know what's going on the other side of that door.
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This landing is in extreme and variable conditions. So the required crab angle is also varying. In these conditions recommended technique is not to fully decrab but land with partial crab (five degrees). I am sure the pilot knows the technique but it hasn't worked to perfection due to conditions..
I prefer to gently and gradually begin to cross the controls early. Say 200 to 300 ft gal.at least
The problem we see in the simulator is the hurried shove on the rudder at the flare and the aircraft hits the deck with drift still there because the rudder should have gently be applied earlier. Often during type rating training in the simulator copilots are given practice at only a 10-15 knot crosswind on landing instead of a steady 35 knot crosswind. The rationale being that in many airlines, copilots are only allowed to land in nothing more than 15 knots. This policy ignores the fact that the type rating should be a command type rating - not a co-pilot rating. In event of incapacitation of the captain, where the co-pilot is now flying solo, it may be a grim experience for the passengers if the co-pilot is not fully qualified and competent to be able to land his aircraft up to the AFM maximum.
In true proon style we have drifted from flogging joysticks to tramping on rudder pedals. There is a new thread on crosswind landing technique elsewhere here.
As much as I am a true believer, I have yet to find a simulator that properly replicates the way an aircraft reacts to inputs during a maximum crosswind component landing. Perhaps the latest sims do, but even the good level D devices from earlier days do not. I never bother to give trainees more than 20 knots crosswind because it is easy enough for the instructor to observe correct technique at that value, regardless of what the sim thinks.
As much as I am a true believer, I have yet to find a simulator that properly replicates the way an aircraft reacts to inputs during a maximum crosswind component landing. Perhaps the latest sims do, but even the good level D devices from earlier days do not. I never bother to give trainees more than 20 knots crosswind because it is easy enough for the instructor to observe correct technique at that value, regardless of what the sim thinks.
I never bother to give trainees more than 20 knots crosswind because it is easy enough for the instructor to observe correct technique at that value, regardless of what the sim thinks.
The captain detected the F/O was worried and insisted the F/O operate the leg and added he would take over if the crosswind was beyond the capability of the F/O. On long final for the landing runway the ATIS indicated a 15 to 20 knot crosswind as forecast. The F/O became increasingly agitated and it reached the situation where the captain took over and landed. During later talk over a beer, the F/O admitted he had lost confidence in his ability to handle crosswinds correctly. Moreover his captains were always happy to conduct the landings themselves thereby relieving him of the possibility of making a fool of himself trying to land without drift. He did not seek extra simulator training at strong crosswind landings because he was concerned it would go on his records. This fear had festered for years.
Some pilots need to build up their confidence and the simulator can work miracles if the instructor is understanding and patient. All in takes is about ten strong 35 knot crosswind landings in the simulator and these can be done by starting from a short two mile visual final which gives the candidate practice at tracking the centre line rather than the usual curve of pursuit. Ideally manually flown without autothrottle and flight director.
Once the candidate can perform the approach and landing in a 35 knot consistently well in the simulator his confidence will soon return and he should take this new found confidence into the real world of crosswind landings on the line. Been there-done that. Until that remedial simulator training is provided a nervous pilot will sweat out every crosswind landing on line. So will his hapless passengers and the airline reputation on social media...
During my first 737 approach in turbulent and windy weather conditions I actually decided to disconnect the AP earlier than I had planned, believing that the rapid fluctuating control inputs were signs of some control system malfunction. I later learned that these kind of control inputs are normal system behaviour for the 737 autopilot.
Last edited by xetroV; 26th Aug 2018 at 12:10.
