14 Landing Gear Flashcards
🛑 NOSE GEAR
Nose gear not down and locked [with either or both forward thrust levers retarted to IDLE, and below 800’ AGL]
When LG DOWN + LOCKED
when at least 1 green indicator light is illuminated > this will deactivate LG warning Horn
Override trigger
bypassing LG lever lock, for ground logic
LG speeds
Extend 270 KIAS- .82M
retract 235 KIAS
Extended 320 KIAS-.82M
Manual extension acces door
- open
- when LG unlock released
O - LG retraction disabled, normal LG extension stilll possible if HYD A pressure available
W - when related handle pulled to limit ( 24 inch/61cm)
AUTO BRAKE DISARM (amber)
- SB lever to down detent [during RTO/landing], except during first 3 sec after touchdown for landing
- Landing made with RTO selected
- RTO selected on GND (for 1-2 sec than extinguishes)
- malfunction in auto brake system
RTO
- how to select
- when and what pressure
- pull autorace select switch
- applies max brake pressure when both thrust levers are retarded to IDLE at or above 88 KTS (below 88 KTS remain armed)
Parking brake warning light
light operate from battery power
Hydraulic brake pressure indicator
normal 3000 psi, max 3500 psi, normal recharge 1000 psi
-NWS and rudder pedal steering
- main and nose gear
- antiskid and autobrake
NWS OVERRIDES rudder pedal steering
- 2 wheel LG unit, nose gear = steerable 2 wheel unit
- antiskid operative with normal + alt brakes. Autobrake ONLY when normal brake
LANDING GEAR
- retraction wheels stopped during retraction
- main gear held up
- nose gear held up
R - Brakes automatically stop rotation of the main gear wheels, nose wheel rotation is stopped by snubbers
M - held up by mechanical uplocks
N - held in place by an overcenter lock and closed by doors which are mechanically linked to the gear
Tire damage during Takeoff
- effect during retraction
- consequence if tire not stopped spinning
E - braking of the wheel may be affected
C - not stopped before entering wheel well: damage may occur. Hence: Fragible Fitting is installed: when a spinning tire impacts it: the gear stops retracting and free falls back to down position. Affected gear can’t be retracted until fitting is Replaced
HYDRAULIC B supplying fluid to :
to raise the Landing gear when all of these occur:
- airborne
- No 1 Engine RPM drops below limit value
- landing gear lever up position
- EITHER main landing gear not up + locked
When LG lever moved to down position:
- which releases uplocks
- How LG extends
- What locks LG
W - HYD A is used to release uplcock
H - LG extends by: HYD pressure, gravity + air loads
W - overcenter mechanical + hydraulic locks the gear at full extension
Manual LG extension
- when possible
- retract LG after manual extension
W - pssibple with LG lever in ANY position
Retract after manual extension:
1 - close manual extension access door
2 - move LG lever to down with HYD A available pressure
3 - move LG lever to UP
Nose Wheel Steering
- when available
- when SYS A, B
W - available on ground with main gear compressed
When
- Positioning LG lever to down > A system available
- when NWS switch to ALTN, will provide SYS B pressure
Brake accumulator
- pressurized by
Antiskid
- available
- NORMAL
- ALTN
P - pressurized by HYD B, normal mode, when HYD A and B is lost, the accumulator provides several applications of braking or parking brake (1 application at V1)
Antiskid
- also available with loss of HYD A AND B
- normal: applies on separate main gear wheels
- alt: applies on both main gear at the same time
To ARM RTO after selecting RTO, all of these conditions must exist:
- when not recycled after takeoff
- aircraft on ground
- antiskid + autobrake system operational
- wheel speed > 60 kts
- FWS thrust lever at IDLE
W - auto brake disarm” light will illuminate after 2 seconds and NO autobrake will be available
AUTOBRAKE
- until when selected
- operation
U - can be selected after touchdown prior to decelerating below 30 KTS GS
O - After landing, when main wheels spinning and thrust levers at IDLE: brings aircraft to full stop
Parking Brake
- powered by
- consequence fault in PB system
P - by EITHER HYD A or B
C - fault in parking brake may cause > ANTISKID INOP light to illuminate
AIR/GROUND LOGIC
6 sensors in total, 2 on each gear
