# How does an alpha vane work?

AsheeshR
• How does an alpha vane work? AsheeshR

The alpha vane is an external probe used to measure the angle of attack. I have been trying to understand how exactly it works, but I can't find any clear explanation or simulation.

Is the vane static or dynamic i.e. does it rotate along its central axis?

Given that it has a significant surface area, I think that it would either:

• Rotate because of the force/drag exerted by the airflow, and give an angle of attack proportional or equal to its angle of rotation
• Measure the force being exerted on it via a force sensor embedded in the surface

Is either of these correct?

In short, how does an alpha vane work?

• For what I have stutied at my instumentation course, it rotates and reads the angle between the current position and the reference position.

You then have several (3-4) of them around the fuselage because a roll maneuver (for example) will alter the measurements asymmetrically and in this way you can compensate for this effect.

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• The alpha vane is an external probe used to measure the angle of attack. I have been trying to understand how exactly it works, but I can't find any clear explanation or simulation. Is the vane static or dynamic i.e. does it rotate along its central axis? Given that it has a significant surface area, I think that it would either: Rotate because of the force/drag exerted by the airflow, and give an angle of attack proportional or equal to its angle of rotation Measure the force being exerted on it via a force sensor embedded in the surface Is either of these correct? In short, how

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