Backcountry Pilot • A gust just picked the airplane up.

A gust just picked the airplane up.

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A gust just picked the airplane up.

Personal experience with wind, and videos of loss of control accidents, point to a common problem with gust on short final deceleration or deceleration after round out. Acceleration on the ground and in low ground effect makes takeoff upset less common. The wing dropping suddenly into a thirty degree bank near stall airspeed is an upset. Unfortunately the bank, rather than potential loss of directional control, is what often gets the pilot's attention. Occasionally the pilot's misunderstanding of how the controls work, and poor muscle memory, lead to use of the aileron with enough adverse yaw to cause loss of directional control.

In the words of Monk, the TV detective, "This is what happened." Either during deceleration on short final or after round out, the gust put a wing down 30 degrees. The pilot used full aileron against the bank followed by some rudder. That startle aileron, without rudder to the stop, resulted in the wing not coming back up smartly. Rather, adverse yaw resulted in an uncontrolled turn or loss of control or unwanted control result. The airplane simply turned off runway and into the ground. In some accidents, startle aileron adverse yaw led to startle pitch up to keep the wing from hitting the ground. Thus, the wing stalled with adverse yaw causing spin. This spin brings the nose down enough to cause the airplane to go on its back. It really looks like a gust just picked the airplane up and flipped it. Either way, it was pilot controlled loss of control.

The probable cause of the accident was that the pilot lost directional control. The pilot lost directional control because he was more interested in levelling the down wing. His use of aileron before rudder sealed his fate. Had he been walking the rudder dynamically and proactively to bracket the centerline no matter what, the gust would not have banked the wing excessively. He would have already reacted to the gust. Already reacted is proactive and because it is proactive it needs to be dynamic. With good rudder movement, moderate instability does not become severe. Aileron orientation as the wing leveller control causes moderate instability to become severe instability. Pilots who always walk the rudder on short final, touchdown, and roll out find gust spread to be less severe. Dynamic proactive rudder movement will keep the centerline between our legs and the wing level. This is basic directional control (lateral control). Gust spread balloon and sink must be vertically controlled with reactive throttle. Dynamic proactive throttle control doesn't work because of the slower reaction of RPM change. We can react with too much and then adjust to boost throttle reaction a bit.

All this is not to say a gust or dust devil cannot pick an airplane up. I lost a parked but not tied down Champ to a dust devil. I just haven't seen as many wind induced rather than pilot control error loss of control accidents. On the ground with little airspeed, we are at the mercy of the wind. A fuel truck blocking crosswind helped with taxi when they were available. In the air, as with the falling leaf, rudder alone will provide directional control and keep the wing level.

instructors may be constrained by school rules about wind training. If the school will not support concurrent instructor training, get out in the wind on your own dime. It will save the school airplane in the long run. Some day you will come back and there is wind and you won't have fuel to go where there is no wind. It is unlikely we will teach that the wind is our friend if we don't believe that the wind is our friend. That would be a big loss for both the instructor and the student. Professional pilots fly in windy conditions. It should be part of the curriculum.

Yes, we avoid big winds like the 75 knots on the front range last week. Actual wind speed and gust spread is generally less of a problem than rapid gust spread. A crosswind of 40 gusting to 60 would put our angle across from downwind corner to upwind touchdown zone white marker groundspeed at 20 and occasionally 0. Other than getting rapid throttle sink rate and glide angle control, I have a very hard time seeing the problem with touchdown at 20 to even zero groundspeed. The 60 gust would, at 120 airspeed, keep the wing flying fine. We just have to lower the nose to prevent going backwards but still flair just a bit to protect the nose gear. Don't let the airplane just setting there at ten feet and zero airspeed unnerve you. When the gust abates, add some power to touchdown on the exact downwind corner slowly and softly.
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Re: A gust just picked the airplane up.

Another great Sunday sermon .
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Re: A gust just picked the airplane up.

As I have stated before, the big crosswind is less of a problem than the light wind. It is easier to train in because it is very obvious how important the rudder is to direct our course in the strong crosswind. It causes less bent tin and skin for the same reason. It is the light crosswind with light gust spread that is the culprit. The one where we may think we can, at slow enough airspeed to actually land on the runway available, use coordinated turns or even aileron alone to level the wing. First rule, use rudder to prevent the wing becoming unhinged. Walk the rudder to bracket and thereby insist on precise directional control. The wing is automatically level or stays in a stabilized bank angle to counter drift in the side slip.

Aileron to cause bank and rudder to control adverse yaw is how it goes at altitude and airspeed in the aerodynamics book. That aileron orientation and practice is not only sloppy at altitude and airspeed, it is dangerous without altitude and airspeed. There needs to be a low altitude orientation and practice. Go fast on takeoff and decelerate to land slowly and softly where desired. Learn how the controls work with various altitude and airspeed considerations. No, we don't want to do the falling leaf on short final. The control response, however, is the same at slow to stall airspeed. And yes, we want to slow to stall to land. Otherwise we don't land...we bounce.

Go get some wind, young instructor. It will be fun and the slower groundspeed is safe.
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Re: A gust just picked the airplane up.

I think a good way to develop good muscle memory is for the pilot to use rudder to maintain straight and level flight in cruise. I think the vast majority of pilots use aileron to keep the wings level in cruise and that is where the bad habits result. Early in my flying it was mostly aileron to keep wings level in cruise now it is mostly rudder. The other day a gust picked up a wing at near a stop and without thinking hit full rudder and cured the problem instantly. I thought to myself did you just do that, full rudder no aileron, yup I did no change in direction still headed the way I wanted. I can only attribute this to my consistent use of rudder to keep wings level in cruise.
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Re: A gust just picked the airplane up.

Absolutely correct, Coyote. My mind goes to "cousin coyote," from my time on the rez. Do you know how many coyote stores Navajos have?
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Re: A gust just picked the airplane up.

Coyote wrote:I think a good way to develop good muscle memory is for the pilot to use rudder to maintain straight and level flight in cruise. I think the vast majority of pilots use aileron to keep the wings level in cruise and that is where the bad habits result. Early in my flying it was mostly aileron to keep wings level in cruise now it is mostly rudder. The other day a gust picked up a wing at near a stop and without thinking hit full rudder and cured the problem instantly. I thought to myself did you just do that, full rudder no aileron, yup I did no change in direction still headed the way I wanted. I can only attribute this to my consistent use of rudder to keep wings level in cruise.
I agree. Most instructors teach aileron for level which the student picks up and muscle memory kicks in. I enjoy flying hands off, and in order to do that you need to keep the wings level with rudder. It's fun taking lower time guys up and showing them what the rudder can really do...
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Re: A gust just picked the airplane up.

Well done David. We need to start the rudder mafia.
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Re: A gust just picked the airplane up.

I learned to fly back in the 80's with an ultralight (Eipper MX). It was 2 axis control with no ailerons. It had lots of dihedral. I still use a lot of rudder in the Champ. :D
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Re: A gust just picked the airplane up.

That one would keep you on your toes, Flyter 1. Manufactured airplanes are well designed. While we emphasize coordination, we need to understand/teach that rudder pulling aileron for trimmed turns is about turns. We also need to teach elevator is for airspeed control, throttle is for glide angle and rate of descent control, and rudder is for directional control on short final. We need to teach that aileron is disruptive on short final and during cruise when we want anti-turn rather than turn. We need to teach rudder as the anti-turn control. And yes, it needs to become muscle memory. Dutch rolls for coordination muscle memory and hands in lap for cruise muscle memory.
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Re: A gust just picked the airplane up.

It sure did Contact. It was easy to control direction with the rudder when that's all you had. :D To make it even more fun, the rudder was in the stick. Feet just went along for the ride.
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Re: A gust just picked the airplane up.

In my first post here the next to last sentence has a critical error. "Don't let the airplane just setting there at ten feet and zero airspeed unnerve you" should have been Don't let the airplane just setting there at ten feet and zero groundspeed unnerve you. Sorry bout that GI.
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Re: A gust just picked the airplane up.

A1Skinner wrote that it is fun teaching younger pilots what the rudder can do to keep the wing level on cross country. Instructors can ethically teach older guys to use rudder only as well on flight reviews. There is no regulation that we have to keep teaching students to kill themselves pulling back on the stick in pattern turns and incorrectly directing their course to target with coordinated turns. There is no regulation that says we cannot teach review pilots not to do things the ACS incorrectly teaches. Continuing to hammer bad muscle memory is wrong. It was wrong during ACS school training, but understandable that lowers have to do and die.

With primary students, you are not wasting any of their stick time teaching them to use the rudder properly to level the wing on a cross country. And if they keep the wing level and insist on directional control by bracketing the centerline extended and centerline with dynamic proactive rudder, the DPE cannot fault that as well. Tail waggers rather than wing waggers get comments from DPEs but cannot be failed for maintaining directional control no matter what with good rudder technique.
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