Lesson 8: INTRO AND DESIGN Flashcards
What is the purpose of a landing gear?
- CONTROL/STABILITY while on ground
- ABSORB loads during takeoff/landing
- No VIBRATIONS
Landing gears must have what?
MECHANISM to absorb LANDING/WEIGHT
For light aircraft what do they use on their main struts and what do they use on their nose gears?
Spring steel for MAIN
OLEO shock absorber for NOSE
What do large aircraft use on their nose/main?
OLEO shock absorber for ALL
Retractable landing gear is used mostly for what type of aircrafts?
LARGE and high SPEED
How do we prevent collapsing with WOW on RETRACTABLE landing gear?
OVER CENTRE mechanical lock down design
What are the 3 types of landing gear arrangement?
Tricycle
Conventional
Tandem
Tricycle gear is most popular for?
higher speed engines
Why do higher speed aircraft have RETRACTABLE gear?
Aerodynamic Efficiency
How do small aircraft nose/tail wheel steer?
Rudder pedals
How do large aircraft steer?
hydraulic steering actuators
steering tiller
rudder pedals
Describe CONVENTIONAL gear?
2 wheels fwd of the CofG and a small wheel at the back
Describe TANDEM gear?
nose and main on CENTRE LINE with outrigger wheels
What gear is used for gliders and military?
Tandem
What is an advantage of SPRING STEEL?
No matter how much it deforms it always comes back
What are the components of a SMALL aircraft NOSE gear?
Steering input Shimmy Damper Oleo strut (piston) Torque Link Axle
What is the purpose of a Torque Link?
Keeps the AXLE aligned
Where are the Torque Links located?
TOP of CYLINDER assembly and to the BOTTOM of the PISTON/AXLE assembly
What are components of a LARGE aircraft landing gear?
Cylinder Assembly Side Strut (brace) Drag Strut (brace) Down-lock Linkage Lock Actuators/Springs Retract Actuator
Purpose of the CYLINDER assembly?
MAIN structural landing gar support
outer case for piston
This component provides LATERAL support and splits into upper/lower to provide PIVOT points for RETRACTION
Side Strut
What is the purpose of a DRAG STRUT?
LONGITUDINAL support for gear RETRACTION
This component PREVENTS the SIDE STRUT from folding
Down-Lock Linkage
What is the purpose of ACTUATORS and SPRINGS?
Helps in locking/unlocking the DOWN LOCK
What is it called when the main gear has 2 or more axle SUPPORTS?
BOGEY/TRUCKS
This component positions the gear in the correct geometry for entering the wheel well?
PITCH ACTUATOR
What do SPIN DOWN PADS do?
Found in wheel well steering to STOP nose wheel rotation during RETRACTION
Which way do nose gears RETRACT and why?
FWD into wheel well to help lock down
Where do we use TAIL SKIDS?
Aircraft with LONG fuselage
This component acts as a shock absorber for the tail
Tail Skid
