Stall Warning System - Cirrus SR22 Pilot Operating Handbook

Section 7 Cirrus Design
Systems Description SR22

Stall Warning System

The airplane is equipped with an electro-pneumatic stall warning
system to provide audible warning of an approach to aerodynamic
stall. The system consists of an inlet in the leading edge of the right
wing, a pressure switch and associated plumbing, and the avionics
system aural warning system.
As the airplane approaches a stall, the low pressure on the upper
surface of the wings moves forward around the leading edge of the
wings. As the low pressure area passes over the stall warning inlet, a
slight negative pressure is sensed by the pressure switch. The
pressure switch then provides a signal to cause the warning horn to
sound, the red STALL warning CAS annunciation to illuminate, and, if
engaged, the autopilot system to disconnect.
The warning sounds at approximately 5 knots above stall with full flaps
and power off in wings level flight and at slightly greater margins in
turning and accelerated flight.
The system operates on 28 VDC supplied though the 2-amp STALL
WARNING circuit breaker on the ESS BUS 2.
7-76 P/N 13772-004
Revision 1