When I was doing upgrade training one of our checkies used to have you fly downwind properly trimmed at 1500 ft in the B767. Then he would quickly slam the controls from stop to stop and nothing happened. A good lesson in leaving it alone. He also taught me to let go the column about every 15 seconds to ensure that we were in trim. Boeings tend to PIO if you waggle the ailerons.

If I can brinag a contribution to the discussion, such a "practice" was blamed announcing: "don't self masturbate", historical "callout" of the 2nd W.W italian air Force pilots, which has still some fans nowadays...

VinRouge and wiggy,

I certainly don't look down on fast jet pilots, or indeed pilots from any other background. What disturbed me about the ex-Lightning bloke I mentioned is that no-one could find a way round his problem however hard they tried. He was the exception - nearly all the others were excellent.

This is from my line training: (skip to 8:05)

I would say utterly boring rather than interesting. Good example of the worst in back seat drivers.

What about old captains flaring with stab trim starting at the 50 ft RA callout?

True. Seen it a hundred times in the 737 and 727 and you get to know the pilots that have that habit. They cannot help themselves. Perfectly stable approach, a well judged flare then suddenly a completely unnecessary stiff arm burst of power followed half a second later by rapid throttle closure. It becomes a reflex movement by some pilots who think they sense a windshear and apply power to prevent the aircraft from falling out of the sky from six inches above the runway. All it does is cause a float.

Any FOQA/FDM data, (always de-identified), will show this - with AP engaged, there is minimal flight control movement until disconnection.

Whether such movements have a material effect upon the flight path can also be examined, but perhaps all the fore-aft and/or left/right movements cancel one another out. Besides, mass alone would tend to dampen changes in the flight path, (but not pitch/roll attitude!).

PJ2

This has been a lively, excellent discussion - I've enjoyed reading all of it - especially some of the old boy's stories.
I've always felt the "Mastaflailers" are doing something more than simply flying the aircraft. It's a nervous thing if you ask me.

Stick shake as you flare and stick push to get the nose wheel on. That the way to do it!!!

When I started in the CRJ, I had a similar nervous habit: I would flail not on the elevator, but on the trim. With a tunnel visioned field of attention, I would trim for an elevator pressure (just what you're supposed to always do, right?) except that was the elevator pressure was what existed only in the last milliesecond. But when you're new, nervous, and tunnel visioned, that last millisecond is effectively your whole world.

Of course, with any amount of turbulence, there are constantly varying elevator pressures, and when trimming for them all, I would never establish a baseline. The trim and elevator were in constant motion (the trim being appropriate for a parcel air already far behind me) toward no particular end, and my already high workload was therefore only increasing, in a chaotic and positive feedback loop.

After I realized this, I taught myself after trimming to not touch the trim for at least a few seconds -- and handle any pitch needs with the elevator only. Then, if and only if I notice that a preponderance of my inputs were in one direction, I would retrim for that... and then repeat: leave the trim alone, fly for a bit, and then reevalutate whether my last few seconds of elevator use are equally up/down, or biased one way; rinse and repeat. Then things calmed down a lot, my workload decreased, which allowed more of my attention to the bigger picture, etc.

If you wait until you are at the end of an escalator before starting to walk, you risk stumbling badly, so we all learn to start walking before we need to - it's easier and faster for the body to adjust your gait to recover from the stumble, than it is to initiate a discrete movement to recover (whilst of course starting to walk).

On what I assume is the same basis, somebody advised me to alternate gentle light left/right pressure on the pedals prior to landing my tailwheel aircraft - if it starts to diverge to the left then I'm more likely to make a good recovery if I make the next rightwards stroke slightly longer and heavier than if I wait for the aircraft to diverge, then have to consciously recognise that I'm turning to the left and that I have to wake up my lazy right foot and mentally calculate how much I have to push it down.

I suspect the neuroscientists would explain this in terms of 'central pattern generators' which are fairly autonomous mechanisms in the spinal cord that control walking and many other repetitive movements. Whether similar mechanisms are enlisted for the manipulation of joysticks, I couldn't say, but I wonder whether making continuous movements is a fundamental part of how we fly - just that some people perhaps take things a little too far.

He never actually crabbed.

You mean never de-crabbed

And he actually tried, (see the big initial left rudder application) but it was way too late; it was a fraction of a second before touchdown which is not enough time for the yaw to occur. Then the yaw due to left rudder combined with the yaw due to the tricycle directional stability added up to way too much. Big overshoot to the left, late recognition and then the opposite yaw to the right happens, etc. and off into the PIO

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

Crabbing does not involve rudder displacement. What kind of rudder displacement "looks like crabbing?"

I know how to crab...what I'm trying to say is that he holds the rudder so that the nose is into the wind...he's crabbing incorrectly

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?

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

"rudder back and forth to crab" :confused: 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.

What does "crab with the rudder" mean? This phrase makes no sense. It is like saying that someone was "trying to cruise with the rudder."

I perhaps should have put the word 'Crab' in quotes.

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.

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.

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..

Generally agree with that technique. One has to be careful of the amount of wing down aileron that is used since spoiler operation has been known to give increased sink. Pilots forget there is a fair amount of inertia taking place once you starting applying rudder to straighten up before touch down whether you are squeezing in some aileron to have the upwind landing gear touching the runway just before the other wheels or not.

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.

True statement indeed. However there is a psychological aspect to be considered. It is not uncommon to fly with a pilot who is quite apprehensive when faced with a significant crosswind landing. Indeed I know of one case recently where the captain offered his first officer the "leg" into a capital city airport where the forecast at the flight planning stage indicated the probability of a 15 knot crosswind. The F/O had 1000 hours on type. The F/O declined to take up the captain's offer.
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...

In my experience, the 737 autopilot itself is quite a high-gain controller, stirring the pot all over the place in comparison to the 777 I flew before. Of course that's partly due to its much lower mass (hence inertia), but I think it's also just a characteristic of its control system.

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.