Another simple mechanical construction. Ive tried to make it resemble the Mooney speedbrake. Interfacing to keyboard via the toggle to momentary switch action circuit.
Shown in retracted position
When flying gliders, it is important that you are able to regulate the amount of air braking. MS-FS has the possibility to assign the airbrake to a joystick axis. I used a similar method as throttle for moving the potmeter with slide mechanism.