Airframes & Systems

holds the landing gear in a longitudinal direction and prevents large bending forces in the shock strut during touchdown and braking

prevents from lateral forces into the suspension => Allows the landing gear to be retracted

struts carries the lateral forces and transfers them to the fuselage structure

the pivot bearing enables the side strut to be folded

protects the structure from serious damage to the wing or fuselage, should the landing gear roll into obstacles at high speed

mechanically locked in the retracted and extended position = some aircrafts an extension lock

Locking pins prevent unintentional gear retraction on the ground

die Felgen

allows the wheel to move vertically to compensate for uneven runway surfaces and landing shocks => the space between the inner and outer shock strut cylinders accommodates the pneumatic spring action (nitrogen) and the damping feature with hydraulic oil

shimmy dampers

with a truck type (Bogie beam) gear => is tilted aft by a hydraulic actuator

Body gear steering is automatically activated at lower taxi speed=> nose gear turns, twisting the body gear => above this speed the body gear is hydraulic centered and the body gear steering is deactivated

manually (Bild right) or automatic (build links)

an override button to override the lever locking mechanism => prevents a gear lever up => possible to retract the landing gear, if there is a malfunction of a strut-load sensor

gear warning :

a) gear is not down and locked

b) Throttle ide

c) below a specified height

d) Flaps are in a landing position 

usually the rims made in two part construction out of forged aluminium alloy in order to reduce the weight

3 or 4 thermal plugs or fusible plugs in the rim => thermal plugs are made of metal or plastic => they become soft at a temperature of approx. 180 Grad and are then expelled from the rims => deflating the tyre = preventing from exploding

Because of its cooler than the tube types

1. Grove 2. Rib

Multiple disk brakes => the stators are fixed and connected by a torque tube to the landing gear structure => the torque tube allows a small axial movement of the stator disk

carbon or steel with lining blocks

brakes are not applied => sufficient space for the rotor disks to rotate between the stator disk => brakes applied: a pressure plate in axial direction => this presses the stators and rotors (wich can move axially) together and against the counter plate

the friction between rotors and stators provide the strong braking effect and converts kinetic energy into heat

return springs pull back the pressure plate when the brake are released

the wear indicator pin indicates the wear of the brake pads by decreasing extension out of the brake carrier.

Brake equalizer mechanical > provide an even load distribution on a truck (Laufrad) main landing gear on the front and aft wheel during breaking => the brake torque tube is connected with the shock strut by the equalizer roads

stores the energy for at least 5 full braking procedures, in the event of both hydraulic systems failing => the accumulator also stores energy for the parking brake

teh nose wheel is usually braked by rubber pads during retraction => inflight brakes systems

the nose wheel is usually braked by rubber pads during retraction => inflight brakes systems

controls the amount of hydraulic pressure applied to the brakes by inputs from the rudder pedals or from the automatic breaking system => z.B. ice ray the tyre can exert very little force before skidding => without anti skid system = stops immediately

constant pre-selected deceleration for a given deceleration distance ==> the auto braking system is also deactivated by an inoperative anti-skid system

very small turning radius on large transport aircraft => the pedals: 8 to 10 gard => hand wheel allows: approximately 80 Grad turn

nose wheel steering has to be switched off to avoid damage

bild