Piper Malibu PA-46-310P Pilot Operating Handbook page 260

PIPER AIRCRAFT CORPORATION
P A-46-310P, MALIBU
SECTION 7
DESCR/OPERATION
Locking-type actuators are used for main and nose gears. The actuator
assembly provides mechanical gear-down locking at the fully extended
position and is hydraulically unlocked. The actuator also acts as the gear
V
brace in the extended position.
Hydraulic pressure for gear operation is furnished by an electrically
powered hydraulic pump (refer to Figures 7-5 and 7-9). The gear is activated
by a landing gear selector handle located to the left of the control quadrant
on the instrument panel (Figure 7-7). The gear handle is mechanically linked
to the gear selector valve under the right forward baggage compartment
floor. Selecting UP or DOWN position directs hydraulic system pressure to
the appropriate side of the landing gear actuating cylinders.
A spring-loaded solenoid prevents the gear handle from being moved to
the gear UP position when the airplane is on the ground. The solenoid is
energized to unlock the handle by a squat switch mounted on the left main
gear. The squat switch is activated when the gear strut is extended at takeoff,
or if the airplane is on jacks. Should the solenoid fail, a small tab protruding
through the handle slot allows the pilot to override the locking feature by
pushing the tab to the right as the handle is activated to the gear UP position.
During the preflight check, be sure that the landing gear selector is in the
DOWN position and that the three green gear indicator lights are
illuminated. On takeoff, the gear should be retracted before an airspeed of
130 KIAS is exceeded. The landing gear may be lowered at any speed up to
170 KIAS.
The nose gear retracts aft turning 90° sideways and is fully enclosed by
doors. A nose-gear door actuating cylinder is located in the nose wheel well.
The door actuating cylinder receives system pressure for actuation when a
timed check valve is engaged by the fully retracted nose gear. The nose gear
extends and doors open when system-up pressure is relieved. (Both are
spring assisted to the down position.)
The main gear retracts inboard into the wing root area. A mechanically
linked door covers the strut assembly.
The landing gear is held in the retracted position by hydraulic pressure.
In the event of hydraulic system pressure loss, the landing gear will remain
up as long as the selector is in the UP position. To extend and lock the gear,
in the event of hydraulic system failure, it is only necessary to relieve the
hydraulic pressure in the gear hydraulic system. An EMERGENCY GEAR
extension control, located directly beneath the gear selector, is provided for
this purpose. Springs assist in nose gear and nose gear door extension and in
locking the gear in the down position. Pulling the EMERGENCY GEAR
control releases the hydraulic pressure holding the gear in the up position
and allows the gear to free fall. After pulling the EMERGENCY GEAR
ISSUED: JANUARY 11, 1984
REVISED: JANUARY IS, 1986
REPORT: VB-1200
7-11