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Would a disconnected surface, especially aileron, deflect upwards as you slow down due to increased alpha? I figure out it is more likely to deflect upwards as you increase your airspeed, thus having more airflow pressure below it and pushing it upwards.

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3 Answers 3

The aileron will point in the direction that would cause the most drag, it will also flutter a bit. And if by increased alpha you mean the aircraft is flying with high alpha like a jet going super slowly forward at a constant altitude with the nose pointing way up into the air at a high angle, then technically the ailerons would go up in relation to their neutral positions. To get high alpha, you gotta pull back on the sticks to pull up the elevator to bring the nose up. Also, when flying in high alpha, it is extremely easy for a plane or jet to tip stall, which will cause it to roll over, which is prevented by gyros or precise controls of the ailerons keeping the roll level. If you lost your ailerons while flying at high alpha, it is not going to be a good day.

The natural tendencies of the ailerons would not be to go up, control surfaces do not want to do that, that is why spoilerons on large jets are pushed up with hydraulic pressure to help give the plane more drag so it slow down when it comes in for a landing.

I really enjoy talking about planes...

Also, Mike is right about the yarn thing, it will also flutter, as would yarn.

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In the case of deflection of a wing or in this case ailerons, whereas it is needed to create a disconnection between the aileron so the aircraft before it is able to turn. The disconncection would cause the air to deflect upwards over the surface of the aileron, as you slow down due to increased angle of attack. It is more likely to deflect upwards as the airspeed is increased, though having more airflow pressure below the wing would push it upwards. This is a well known military maneuver called Pugachev's Cobra. But in commercial aviation you do not exploid such knowledge due to the safty restrictions.

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Since the ailerons are disconnected, they would trail at the same angle as a tuft of yarn taped to their trailing edge. That would, I assume, be an angle that minimizes drag.

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