Landing Gear Flashcards
When does the landing gear system automatically switch from LGCIU?
At the end of each retraction and automatically if a failure is detected.
What is the function of the safety valve in the landing gear system?
Shuts off hydraulic pressure to the actuators when the aircraft speed exceeds 260kts and restores pressure with the landing gear lever down and speed below 260kts.
By which means does the landing gear extend when using the gravity gear extension?
Combination of gravity, aerodynamic force and locking springs
By which LGCIU are the lights on the landing gear indicator controlled?
LGCIU 1
What do the LGCIUs use to supply air/ ground data?
The shock absorber position.
When does the master BSCU automatically change over?
At each down selection of the landing gear lever or when a fault is detected.
By what are the landing gear and doors controlled?
Two LGCIU’s
How does the anti skid system determine wheel slip ratio?
By comparing aircraft speed from the ADIRUs to the tire speed from tachometers
What is the deceleration rate and when does the autobrake start with LO selection?
4 seconds after spoilers deploy. Rate 1.7m/s2
What is the deceleration rate and when does the autobrake start with MED selection?
2 seconds after ground spoilers deploy. Rate is 3m/s2
What is the deceleration rate and when does the autobrake start with MAX selection?
As soon as ground spoilers deploy, max braking applied.
If flight is conducted with the L/G down, and a failure happens that causes the aircraft to revert to alternate law, what will happen?
The aircraft will revert to direct law immediately.
After how many seconds must the landing gear retraction or extension sequence complete before a warning comes up?
30 seconds
Which warning comes up if the gear retraction sequence has not been completed in 30 seconds?
Gear not UPLOCKED
Which warning comes up if the landing gear extension sequence is not completed in 30 seconds?
Gear not DOWNLOCKED
When do you get the brakes hot message?
If at least one brake is >300C
Why must the brake temperature be below 300 degrees prior to takeoff?
To prevent ignition of any hydraulic fluid that leaks on the brakes.
When does the BSCU do a self test?
When normal braking is active and at least one engine is running and the BSCU receives a gear DOWNLOCKED signal from the LGCIUs.
When is maintenance to the brakes required?
- one brake >600C and other brake on same gear 150
- Average temp of one gear is 200C more than the other
- Any brake temp >900C
- a fuse plug has melted
How are the landing gear and doors controlled and actuated?
Electrically controlled and hydraulically actuated
What is the function of the LGCIUs?
- control extension/ retraction of the gear and operation of the doors
- supply information about gear to ECAM
- sends signals aircraft in air or ground to other systems
What information of the landing gear is send to the LGCIUs?
- locked down/ up
- shock absorbers compressed/ extended
- landing gear doors open/ closed
Which information about the cargo doors is send to the LGCIUs?
Position of manual selector valves, locking shaft, locking handle, safety shaft, door sills.
Which information about the flaps is send to the LGCIUs?
Signals from 4 flap disconnect proximity switches
