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Avoiding Wind Flips
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Control Positions While Taxiing
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 By John Lorenz
Breezes don’t bother most aircraft during taxi, but winds are another story. More than one aircraft, including mine, has been flipped over by a gust, and it leaves an unpleasant memory. There are two strategies for avoiding the embarrassment and expense of flipping an aircraft. One is to never taxi in a wind (good luck), the other is to keep ailerons and elevator moving to the proper positions relative to the wind during taxi.
Bluntly, few pilots have a clue about how to move the flight controls when maneuvering an aircraft on the ground. We get away with this only because most of the time the wing is edge-on to the wind and not vulnerable. However, the empennage and the broad surface of the wing are absolutely huge sail areas when they get turned sideways to the wind. If that rare gust can lift a flying surface just a bit so that a strong wind can act on the underside instead of the edge of a wing even temporarily, the wind forces increase dramatically. As the wing goes up, the flat-plate surface area exposed to the wind increases exponentially, and the related increase in force almost demands that the process goes to completion once it’s started. The aircraft will go up and over so quickly that the pilot has no time to react. Prevention, not reaction, is your only option.
Ailerons — Never let the wind hit the underside of the aileron on the upwind wing. Aileron positioning should be neutral for a direct headwind or tailwind, and for side winds directly off the wingtip. For the more common quartering winds, however, the rule of thumb is “turn into a headwind, turn away from a tailwind.” Positioning the yoke as if to turn toward an oncoming, quartering headwind raises the aileron on the upwind wing and the wind hits the top of that aileron from the front, pushing the upwind wing down, minimizing the chances of a gust acting on the underside of the wing. Positioning the yoke as if to turn away from a quartering tailwind lowers the aileron on the upwind wing so that the wind still hits the aileron’s top surface but from behind, again pushing the wing down. Demonstrate the effectiveness of this by noting how the whole aircraft rocks when pointed into a strong wind, parked, as the yoke is moved from side to side. An aircraft in motion is more vulnerable.
Elevator in a Tailwind — Likewise, never let the wind hit the underside of the elevator. In a tailwind, whether direct or quartering, the yoke should be held full forward as if trying to dive away from the wind. This keeps the elevator down and the wind hitting the top of it, preventing a gust from getting underneath and lifting the tail. In a taildragger, it has the added advantage of pressing the tailwheel against the ground for better steering. The rule of thumb is “dive away from a tailwind.” This position should be held religiously during the vulnerable taxi-turns from crosswind to downwind and when taxiing downwind.
Elevator in a Headwind — The best elevator position when taxiing into a direct or quartering headwind differs for a taildragger and a tricycle-gear aircraft. Hold the elevator neutral for a tricycle-gear aircraft to keep the wing edge-on into the wind: pulling the yoke back and bringing the elevator up only lets the wind push the tail down, exposing the underside of the wing as well as raising the nosewheel and diminishing steering authority. For a taildragger, however, holding the elevator up in the climb position is best. The exposure of the underside of the wing due to the tail-down, three-point stance is unfortunate but fixed, and elevator positioning won’t change it. However, up elevator helps the wind hold the tail wheel firmly to the ground for steering. So, in headwinds and quartering headwinds, hold the elevator up as if in a climb when taxiing a taildragger, but hold it neutral as if in cruise for a tricycle-gear aircraft. Either “climb into the wind” (taildragger) or keep the elevator neutral (tricycle).
Putting it together — During taxi, it’s often necessary to make the ailerons go one way while the elevator goes another in response to wind direction, neither having any relationship whatsoever to the coordinated control positions familiar from airborne maneuvers. They’re also unrelated to the rudder-pedal motions that are controlling the nose wheel and direction of travel. Putting it together is like patting your head while rubbing your stomach. Keep the aircraft moving in the desired direction with rudder pedals and power, then “turn and climb into the wind” or “turn into the wind,” (taildragger vs. tricycle in a headwind) with the yoke. If the wind is toward you from the left, the yoke should be held full aft (taildragger) or neutral (tricycle-gear aircraft), and turned full left. In a tail wind, “turn and dive away from the wind” in both types of aircraft: if the wind is coming from behind your right shoulder, the yoke should be turned full left and pushed forward.
It gets confusing when making taxi turns, when the wind doesn’t change but its direction relative to the aircraft axis does. Visualize it: there is a strong north wind and you are taxiing to the northwest but need to turn onto a northeast-bound taxiway. In a taildragger, the yoke should be full aft and canted fully to the right before the turn, but it must be aft and changed to full left during the right-hand turn. On the other hand, as you turn so that a quartering headwind becomes a quartering tailwind (as in turning onto a southwest-bound taxiway in the scenario above), the yoke should go from one corner of its range of motion (aft and right) diagonally to the opposite corner (forward and left). No half measures either; bring the controls to their stops each time.
It’s learnable and definitely worth the effort for that time you took off when the wind was calm but picked up to howling by the time you landed. However, it’s better to learn it through practice than by reading about it. Practice during taxi, or even just while sitting in a swivel chair or maybe walking in different directions along the flight line while feeling the wind, making imaginary control changes with your hands. If nothing else, it will give people something to whisper about. |
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