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Let us say we have a right quartering headwind, we should “fly into the wind” so yoke to the right then that our right aileron will deflect up and left aileron down. How does this avoid the chances of weathervaning since our right main wheel will be more suspended on the ground? That should yaw our airplane to the right even more like in the concept of “torque effect” for left turning tendency (which results in yawing to the left since our left main wheel is suspended more on the ground).

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This is part of basic training. With a right quartering into the wind its ailerons into the crosswind, yoke pressure forward a bit.

Think of it as a headwind component and cross wind component. The headwind component (increased by taxiing) will act on the ailerons, helping to "hold down" the upwind wingtip.

With a quartering tailwind while taxiing or at rest, the ailerons are reversed (upwind aileron down).

Keep in mind one also has differential braking (and rudder) help to control weathervaning. Also, the "prop blast" will make the rudder more effective.

Once the plane is moving fast enough to be up on one wheel, rudder control will be effective.

the stronger the crosswind, the harder control becomes

That's why crosswind limits are applied for each aircraft. Landing in a cross wind essentially involves the same procedures.

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The primary purpose of the illustrated aileron corrections is not to prevent "weathervaning"-- rather it is to prevent the aircraft from tipping over so that the "downwind" wingtip contacts the ground, and also to allow the banked wing to generate a horizontal force component to oppose the horizontal sideforce generated by the wind blowing against the fuselage and other aircraft components, which would otherwise tend to create the "skipping" or "sliding" effect illustrated in the upper diagram, especially if the wing is actually banked in the wrong (downwind) direction as illustrated in the upper diagram.1

However, consider-- weathervaning is the biggest concern when we are decelerating, or taxiing at low power. In these cases the engine is at low power so we don't have a strong propwash over the tail to improve the effectiveness of the rudder. Say for simplicity the engine is generating zero thrust and zero propwash. Is it not clear that the effect of the crosswind on the rear fuselage will generate a much stronger nose-to-right "weathervaning" torque if only the left main wheel is on the ground (and the left main wheel is therefore effectively acting as the "pivot point") than if only the right main wheel is on the ground (and the right main wheel is therefore effectively acting as the "pivot point")? If this is unclear, imagine a hypothetical extreme case where the main landing gear legs are attached all the way out at the wingtips-- now the geometry should be clear.

This effect is even more pronounced in a tailwheel aircraft, but it is also present in an aircraft with tricycle landing gear. Yes, in the aircraft with tricycle gear, the gear is behind the center of gravity, but the center of lateral area of the aircraft still typically lies behind the main gear.

By the way, in a tailwheel aircraft with the tailwheel on the ground, we have the additional effect that because the aircraft sits nose-high, lowering an aileron creates much more drag than raising an aileron. So the illustrated aileron input creates an additional yaw torque component in the "downwind" direction, opposing "weathervaning". This yaw torque component created directly by the aileron deflection would be present even if the aircraft were exactly wings-level, with both main wheels pressing equally onto the ground.

In fact, even while running along on the main wheels in a tailwheel aircraft, in a high-speed taxi (or extended touch-and-go landing) with the tailwheel in the air, a right aileron input generates a strong left yaw torque and a left aileron input generates a strong right yaw torque. An instructor showed this to me in his Luscombe, claiming that the ailerons (used in the "wrong-way" sense) were actually more effective than the rudder in steering the aircraft on the ground. I don't know if this claim is actually true, but it was clear the ailerons were quite effective at generating a "wrong-way" yaw torque. During this demonstration, the angle-of-attack of the wing was kept low enough that both main wheels stayed in contact with the ground, while the tailwheel stayed off the ground.

Footnotes:

  1. While taxiing, we generally keep all the wheels on the ground (at least in a tricycle gear aircraft) and so the actual bank angle we'll achieve is small, due only to the compression of the tire and landing gear leg. In this case the primary purpose of the "upwind" aileron input is to prevent the "upwind" wheel from accidentally lifting into the air, but whatever slight bank angle we do achieve will serve the function noted here. For actual take-off and landing, we'll spend some time with the "upwind" wheel on the ground and the "downwind" wheel off the ground, so the bank angle we'll achieve will be larger, and will serve the function noted here to a much greater extent than during taxiing. Both during taxiing and during landing, anything we do to increase the ground contact pressure of the upwind wheel and decrease the ground contact pressure of the downwind wheel will help prevent weathervaning for the reasons given in this answer. During takeoff, when the engine is delivering a lot of a thrust, this may no longer be true, as the question itself hints (by reference to "torque steering"), but during takeoff we generally have ample yaw control anyway, especially in a single-engine aircraft with a strong propwash over the tail.
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From the illustration, I deduce that you’re talking about landing in a crosswind. Aileron input will not control the tendency of the aircraft to weathervane. What it is used for in crosswind landings is maintaining a flight track along the runway centerline i.e. you’re holding the airplane on center line using aileron input. Rudder input is then used to keep the longitudinal axis of the aircraft parallel to the runway. i.e. use rudder input to keep the nose pointed at the far end of the runway. This rudder input will be independent i.e. uncoordinated with aileron input, as opposed to coordinated aileron and rudder inputs like those used in turning the airplane.

If done properly, the upwind main landing gear will make contact with the runway first. Once that happens, the pilot allows the downwind main landing gear to touchdown on the runway by relaxing aileron pressure somewhat. Again, the same control inputs i.e. aileron input to track centerline and rudder to keep the a/c aligned with centerline are used until the nosewheel touches down a the airplane has significantly slowed. At this point full aileron deflection into the wind will be used and directional control usthe airplane has significantly slowed. At this point full aileron deflection into the wind will be used and rudder will be used for directional control in taxi.

As for torque effects during touchdown, if done properly, a crosswind landing should produce minimal effect yawing like that. Any tendency of the airplane to yaw should be immediately corrected with rudder input to keep the nose pointed at the far end of the runway. Poorly controlled crosswind landing with a hard touchdown often will cause the airplane to veer off in the upwind direction, particularly if the pilot relaxes control pressures at the instant of touchdown. Crosswind landings require a diligent pilot to continuously fly the airplane until it is slowed to taxi speeds.

During taxi, the idea in control positioning is not to use ailerons to prevent weathervaning, but to prevent a gust or wind from picking up the upwind wing and tossing the airplane over. Any kind of minor loads on the landing gear from this are insignificant next to the risks associated with such an event. This is particularly necessary with seaplane operations due to a floatplane’s CG located so high relative to the water surface.

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    $\begingroup$ Title says they are referring to taxiing. $\endgroup$ Nov 12, 2023 at 16:13
  • $\begingroup$ Add additional comments about taxiing $\endgroup$ Nov 12, 2023 at 18:46

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