Visit http://www.spaceagecontrol.com/AirDataProbes for information on pitot probes, pitot-static probes, air temperature probes, static pressure ports, and angle of attack (AOA) sensors.
Angle of Attack Sensor, Angle of Sideslip Sensor, Alpha Vane, Beta Vane
The above sensor consists of two vanes that are mounted ninety degrees from each other on a shaft. They are raised up on stands that are as described above at least two boom (or shaft) diameters above the axis of the boom, so as to reduce turbulence. Due to the two-vane arrangement, two different angles are detectable; the angle of attack (AOA) and the yaw angle. The angle of attack is basically the upward-downward angle of the aircraft, where as the yaw angle measures the side-to-side angle that the aircraft undergoes as it moves slightly from right to left. This side-to-side motion is important for several reasons; a pilot may intentionally be trying to move in this side direction which would make the precise angle of motion a handy value to know, also, when the wind and air are turbulent, slight variations in this side-to-side direction need to be corrected for by the pilot, thus making the information very important.