Landing Gear; Shock Absorption - Cessna 152 Training Manual

CESSNA 152 TRAINING MANUAL

Landing Gear

The landing gear is of the tricycle type with a steerable nose wheel and two
fixed main wheels. The landing gear may be equipped with wheel fairings for
reducing drag.
The steerable nose wheel is mounted on a forked bracket attached to an air/oil
(oleo) shock strut. The shock strut is secured to the tubular engine mount.
Nose wheel steering is accomplished by two spring-loaded steering bungees
linking the nose gear steering collar to the rudder pedal bars. Steering is
afforded up to 8.5 degrees each side of neutral, after which brakes may be
used to gain a maximum deflection of 30 degrees right or left of center. During
flight the nose wheel leg extends fully, bringing a locking mechanism into place
which holds the nose wheel central and free from rudder pedal action.

Shock Absorption

Rudder Steering
Shock absorption on the
main gear is provided by
the tabular spring-steel
main landing gear struts
and air/oil nose gear shock
strut, commonly known as
the "oleo". Because of this
the main gear is far more
Shock
durable than the nose gear
Strut
and is thus intended for
Shimmy
the full absorption of the
Damper
landing.
Correct extension of shock
Illustration 4a Nose Wheel Components
strut is important to
proper landing gear
operation. Too little extension will mean no shock absorption resulting in shock
damage during taxi
and landing. Too much extension will result in difficult nose wheel steering and
premature nose wheel contact on landing may occur. Should the strut extend
fully while on the ground the locking mechanism will cause a complete loss of
nose wheel steering. During the pre-flight inspection, check the shock strut for
proper extension, (approximately two inches or five centimetres), and check
the shock absorption properties (lift the nose of the aircraft and release to
ensure a firm but resonant feel).
A hydraulic fluid-filled shimmy damper is provided to minimize nose wheel
shimmy. The shimmy damper offers resistance to shimmy (nose wheel
oscillation) by forcing hydraulic fluid through small orifices in a piston. The
by D. Bruckert & O. Roud © 2004 Page 32