32 Landing Gear Flashcards
What is displayed at the top of the WHEEL SD page?
Spoilers
How many green triangles are needed per gear to confirm locked down?
One (one LGCIU needs to confirm green triangle)
What does two amber XX’s mean in place of a green triangle on the WHEEL SD page?
One LGCIU has failed
What does an amber X mean in place of an arrow for spoilers?
Spoiler position not valid
When does a green arc appear over brake?
When one brake >100degC
When does an amber arc appear over brake?
When one brake >300degC
When does N/W STEERING appear in amber on the WHEEL SD page?
System failure, or
Both BSCUs fail, or
Y HYD SYS LO PR, or
A/SKID + N/WHEEL STRNG pb off
Maximum brake temperature for take off without any brake fans? With brake fans?
300degC without fans, 150degC with fans
When do the fusible plugs melt in the tyre? Why do they do this?
When brakes reach 800degC to prevent tyre burst
Maximum speed with landing gear extended? VLE
280kt/M0.67
Maximum speed for landing gear extension? VLOe
250kt/M0.60
Maximum speed for landing gear retraction? VLOr
220kt/M0.54
Maximum tyre speed?
195kts
Maximum wiper operating speed?
230kts
Maximum window open speed?
200kts
Maximum speed with one tyre deflated?
7kts
Maximum speed with two tyres deflated (same side)?
3kts
What speed is tiller disabled
80kts
What speed does rudder pedal disconnect from NWS?
130kts
Various types of braking?
Normal (G)
Alternate (with anti skid) (Y)
Alternate (max 1000psi) (Y)
Hydraulic accumulator pressure (Y)
Why limited to 1000psi?
Prevent wheel locking
How many full braking applications on accumulator braking?
7
Describe auto brake deceleration modes
Low - spoiler activation + 2s @ 2/s
Med - spoiler activation + 2s @ 3m/s
Max - when thrust levers are closed above 72kts
Autobrake arming conditions
Green hydraulics
Anti skid
1 x ADR
When will DECEL light come on?
When 80% braking achieved
How does anti skid function?
Maintains wheel speed just above impending skid.
Disabled below 20kts
Compares wheel speed to aircraft speed and if not equal releases the brakes
Max tyre speed
195kts
QRH procedures for gear/brakes?
Loss of braking
Gravity gear extension
Landing with abnormal gear
Asymmetric braking
When are auto brakes available?
Normal Brakes
The landing gear panel on the middle console is connected to which LGCIU?
LGCIU 1
How many degrees of nose wheel steering do we get from:
Rudder pedals
Hand wheels
And at what speed to we have none?
Rudder pedals
+- 6 progressively less to 130kts
Hand wheel
+-75 progressively less to 80kts
On the ECAM
We see NW STRG DISC in green meaning the selector is in the towing position.
When does this memo turn amber?
If one engine is running
Below what speed does anti skid deactivate ?
20kts
Careful tasting
How does anti ski work?
The speed of each main wheel is measured using a tachometer and is compared to the aircraft reference (ADIRU) speed.
If the speed of the wheel goes below 0.87 x ref speed then it is skidding and anti skid kicks in.
Above what speed to ground spoilers extend?
72kts
Therefore during an RTO autobrake wont kick in unless above this speed!
When does auto brake kick in?
Ground spoiler extension
When is auto brake activated?
When ground spoilers deploy
Why is brake pressure on alternate without anti skid limited to 1000psi?
To stop wheel locking and tyre burst
Why is the break temp limit 300 degrees?
Because that temp ensures the hydraulic fluid will not ignite in the wheel well.
When does the LDG GEAR safety valve operate?
When the aircraft is flying faster than 260 kt, a safety valve automatically cuts off hydraulic supply to the landing gear system. Below 260 kt, the hydraulic supply remains cut off as long as the landing gear lever is up.
What do the LGCIU’s receive position information from?
Landing gear
Cargo door
Landing flap systems
