Piper PA-32R-301T SARATOGA S, Руководство по обслуживанию

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GENERAL
This section contains instructions for the overhaul, inspection, and adjustment of the various components
of the landing gear and brake systems; adjustments for the electrical limit, safety and warning systems.
With the exception of brakes, this section does not cover the hydraulic function of the landing gear.
This information may be found in the hydraulic section, chapter 29.
DESCRIPTION AND OPERATION
The PA-32R-301/301T is equipped with a retractable tricycle air-oil strut type landing gear which is
hydraulically operated by an electrically powered reversible pump. A selector handle on the instrument
panel to the left of the control quadrant is used to select gear up or down positions.
Gear positions are indicated by three green lights located above the selector lever for gear down and
locked position. A red light located at the top of the instrument panel indicates gear unsafe condition.
There is no indications that the landing gear has fully retracted other than all lights are out. When the
landing gear moves to the down position and each downlock hook moves into its locked position, a
limit switch is actuated to its normally closed (NC) condition. This will illuminate a green light
indicating that the individual gear is safely down and locked. The activation of all three downlock
switches will also shut off the hydraulic pump. As the instrument lights are turned on, the green lights
will dim. When the gear begins to retract and the downlock hook disengages, the down limit switch
actuates to the (NC) position and is in series with the (NC) circuit of the up limit switch allowing the
gear unsafe light to come on. The gear unsafe light will remain on until the gear is up and all up limit
switches are actuated to their normally open (NO) position.
The red gear unsafe light also operates simultaneously with the warning horn. Both serve a dual pur-
pose. Their primary purpose is to give warning when power is reduced below approximately 14 inches
of manifold pressure and the landing gear has not reached the down and locked position. This circuit is
controlled by the three paralleling down limit switches connected in series with the throttle switch. The
secondary function of the warning light and horn is to give warning when the gear selector handle is
up while the airplane is on the ground or airspeed is below that required to close the hydraulic valve
and the pump switch of the backup gear extender unit. Airplanes that have had the backup gear extender
unit removed, or the system not installed, will get the warning light and horn only when the flaps are
extended to 10 or more. A micro switch installed on a cam located on the flap torque tube will when
closed, give an indication that the gear is not down and locked regardless of the gear lever up or down
position. When the airplane is setting on the ground, the warning circuit is controlled through the (NO)
side of the safety switch (squat switch) located on the left gear and on the up position of the gear selector
lever. When the airplane is raised from the ground, such as in flight, far enough to move the safety
switch to its (NC) position, then current is directed in series through the hydraulic pressure switch, the
pump switch (providing airspeed has actuated the switch to its (NO) position), and the up positioned
selector lever. The up limit, safety, pressure and selector switch, and pump solenoids are all protected
by the landing gear control and warning circuit protector. (Refer to Chapter 91 for electrical schematic.)
– NOTE –
PA32R-301 airplanes with s/n’s 32R-8013001 thru 32R-
8613005 and 3213001, and PA32R-301T airplanes with s/n’s
32R-8029001 thru 32R-8029110, 32R-8029121 thru 32R-
8629006 and 3229001 thru 3229002 may be equipped with a
back-up landing gear extender. Refer to Piper Service Bulletin
No. 866A
PIPER AIRCRAFT
PA-32R-301/301T
MAINTENANCE MANUAL
32-00-00
Page 32-1
Reissued: July 1, 1993
3A18