Stall Warning System; Description And Operation; Functional Tests; Ground - Piper 6X Maintenance Manual

4.

Stall Warning System

A.

Description and Operation

This system consists of two lift detectors located on the leading edge of the left wing, at wing station
174.00, that are electrically connected to the flap position switch and stall warning horn. As a stall
condition is approached, the lift detector will activate the stall warning horn.
B.

Functional Tests

(1) Ground

The following ground check will determine if the lift detectors are correctly connected and
functioning properly. It also verifies the correct adjustment of the flap position switch. This
ground check does not test the proper adjustment of the lift detectors.
(a) Apply electrical power to the airplane.
(b) Extend flaps to the 10° position. The 0° and 10° flap position activates the inboard lift
detector only. Gently lifting the inboard lift detector vane should activate the stall warning
horn. Gently lifting the outboard lift detector vane should not activate the stall warning
horn.
(c) Position the flap to 25° or 40°. Gently lifting on the outboard lift detector vane should
activate the stall warning horn. Lifting on the inboard lift detector vane should not activate
the stall warning horn.
NOTE: In steps (b) and (c), above, if the stall warning horn sounds when it should not, or
(d) Remove electrical power from the airplane.

(2) Flight

WARNING: ALL FLIGHT TESTS SHALL BE CONDUCTED BY A QUALIFIED PILOT
The only way to test the accuracy of the lift detector setting/adjustment is in-flight. Several test
flights and alternate adjustments (see Lift Detectors, Adjustment, below) may be required
before the desired setting is obtained.
(a) Inboard lift detector:
1
2
3
4
(b) Outboard lift detector:
1
2
2K15
THE NEW PIPER AIRCRAFT, INC.
PA-32-301FT / 301XTC
MAINTENANCE MANUAL
does not sound when it should, the fault may be the flap position switch being out
of adjustment. See Wing Flap Controls, Rigging and Adjustment, 27-50-00.
EXPERIENCED IN THIS PARTICULAR MAKE AND MODEL OF AIRPLANE.
Place the airplane in a flaps up, power off configuration.
NOTE: When 5 to 10 knots above the airspeed at which stall warning is anticipated,
limit airspeed reduction rate to approximately one (1) knot per second, to
ensure unaccelerated stall conditions.
Fly the airplane into a stall condition.
Note the speed at which the stall warning comes on.
The stall warning should come on not less than five knots, nor more than ten knots,
before the actual stall occurs.
Place the airplane in a configuration of flaps down 40°, power off.
NOTE: When 5 to 10 knots above the airspeed at which stall warning is anticipated,
limit airspeed reduction rate to approximately one (1) knot per second, to
ensure unaccelerated stall conditions.
Fly the airplane into a stall condition.
27-30-00 PAGE 15
Jun 1/03