King Air C90GTi, Pilot Training Manual

Page: 288 / 557

The shimmy damper, mounted on the right
side of the nose gear str ut, is a balanced hy-
draulic cylinder that bleeds fluid through
an orif ice to dampen nosewheel shimmy.
WHEEL WELL DOOR
MECHANISMS
The landing gear doors consist of one set of
nose gear doors and two sets of main gear
doors. Landing gear doors are mechanically
actuated by gear movement during exten-
sion and retraction.
The nose gear doors are hinged at the sides
and are spring-loaded to the open position.
As the landing gear is retracted, a roller on
each side of the nose gear assembly engages
a cam assembly on each door, and draws the
doors closed behind the gear. The reverse
action takes place, and spring-loading takes
effect as the nose gear is extended.
The main gear doors are hinged at the sides
and are connected to a landing-gear, door-
actuator torque tube assembly with two push-
pull links (Figure 14-3). The torque tube
assembly also contains an uplock roller sup-
port assembly which, when contacted by the
uplock cam on the main gear shock cylin-
der, rotates the torque tube to pull the doors
c l o s e d u p o n g e a r r e t r a c t i o n , o r p u s h t h e
doors open upon gear extension.
R o l l e r m ove m e n t i s t r a n s m i t t e d t h r o u g h
linkage to close the doors. During exten-
sion, roller action reverses cam movement
to open the doors. When the cam has left the
roller, springs pull the linkage over-center
to hold the doors open.
STEERING
Direct linkage to the r udder pedals per mits
nosewheel steering when the nose gear is
down. One spring-loaded link in the system
KING AIR C90GTi/C90GTx PILOT TRAINING MANUAL
14-3
FOR TRAINING PURPOSES ONLY
14
LANDING
GEAR
AND
BRAKES
UPLOCK ROLLER
SUPPORT ASSEMBLY
UPLOCK ROLLER
DOWNLOCK
SPRING
DOWNLOCK
SPRING
DOOR ACTUATOR TORQUE
TUBE ASSEMBLY
UPLOCK CAM
VIEW LOOKING AFT
OUTBOARD DOOR INBOARD DOOR
Figure 14-3. Main Gear Door Mechanism