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Horizontal stabilizers stall, so I was wondering, is it possible for an aileron to stall? If yes, at what angle of attack?

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    $\begingroup$ The equivalent of the horizontal stabilizer (which is a wing) is not the aileron but the main wing. The aileron (a flight control surface) is the equivalent to the elevator (also a flight control surface attached to the horizontal stabilizer) $\endgroup$ – Florian Jun 8 '18 at 17:07
  • $\begingroup$ Ok, So can they stall(elevator and aileron)? $\endgroup$ – David Teahay Jun 8 '18 at 18:25
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    $\begingroup$ @DavidTeahay As John says, you can't view the aileron in isolation because all it does is modify the wing. But the wing can of course stall - this being the most common type of stall. $\endgroup$ – Dan Jun 8 '18 at 19:05
  • $\begingroup$ Ok,understood🙏....so at what angle of aileron deflection does an aileron start to create less lift more drag,at what angle does it become inefficient... @Dan $\endgroup$ – David Teahay Jun 8 '18 at 19:13
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The aileron itself doesn't stall, being part of the main wing. But since it alters the camber of the main wing it changes the local angle of attack in effect. On older airplanes, a down aileron at low speed could trigger a stall separation of the wing in the area of the aileron and if you applied aileron to correct a wing drop at the stall, it would just speed things along and over you go. This was one of the reasons for slots in front of the ailerons on airplanes like the Globe Swift.

Not sure how it is taught today (I learned to fly in 1975) but long ago pilots were always taught to avoid aileron input close to the stall and keep wings level with rudder, although on modern airplanes with washout and other features to delay stall near the tip you can generally get away with it.

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    $\begingroup$ Nothing has changed. Aileron neutral in a stall is how to prevent a spin due to adverse yaw caused by down aileron deflection. $\endgroup$ – Pugz Jun 8 '18 at 19:15
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    $\begingroup$ @DavidTeahay It's not at all about deflection and you really shouldn't think in those terms. Typical critical AoA is around 15-20degrees against the relative airflow. $\endgroup$ – Dan Jun 8 '18 at 19:26
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    $\begingroup$ @David Teahay you are thinking way too hard.... In normal flying it's not an issue. But if you find yourself just above stall speed somehow in some situation, you should have been trained to avoid large aileron inputs until you've gained some speed. There are no published limits of any kind, just good judgement and airmanship. $\endgroup$ – John K Jun 8 '18 at 21:27
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    $\begingroup$ Your advice for flying close to stall is still sound, and washout is really not a modern feature. Physics hasn't changed, and the aircraft engineers half a century ago were at least as competent as those of today. +1 $\endgroup$ – Peter Kämpf Jun 9 '18 at 9:08
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    $\begingroup$ Well as an old timer, when I say "modern" I mean, oh, post 1940 lol ;) $\endgroup$ – John K Jun 9 '18 at 16:18

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