stall warning system
a retro fitted stall warning sender in the wing leading edge from ACI
Most aircraft are equipped with a Stall Warning system of some type. On some
older aircraft, a small moveable flap located on the leading edge of the wing
engages an electrical switch in the cabin, which activates a stall warning
buzzer or horn. On some later aircraft, the system is pneumatic, with a small
slot in the leading edge of the wing. Both types sense approach to stall, and
sounds a device in the cabin, warning of impending stall.