BRAKES AND LANDING GEAR Flashcards
To prevent exceeding Vle, a safety valve isolates the GREEN HYD supply above what speed?
260 kts
What HYD SYS powers the main gear?
GREEN SYS
What HYD SYS and computer powers the nose gear?
GREEN SYS and the BSCU (Brake Steering Control Unit)
What does the LGCIU do?
- Control door and gear movement
- Monitor gear and door positions
- Sends gear info to ECAM
When does the LGCIU alternate control between each other?
At the end of each gear cycle or during a failure
What are the 5 braking modes?
- Normal
- Alternate with anti-skid
- Alternate without anti-skid
- Accumulator only braking
- Parking brake
On the wheels page, what does the triangles represent?
Left is LGCIU nr 1
Right is LGCIU nr 2
What is the action when GEAR UPLOCK is displayed?
Do NOT raise the gear lever
What does a green arc on the brakes page mean?
Brake temp is over 100 deg C. Shows above the hottest brake
What does an amber arc on the brakes page mean?
Brake temp is over 300 deg C. Shows above the hottest brake
What does REL stand for on the wheel page?
Anti-skid function is ready
What could an amber N/W STEERING memo indicate?
- Failure of the nose wheel steering system
- Failure of both BSCU:s
- Low GREEN HYD pressure
- A/SKID and N/W STGR switch is selected OFF
What could an ANTI SKID memo indicate?
- Both BSCU channels failed
- A/SKID and N/W STGR switch selected off
- Anti skid failure
- Low YELLOW HYD pressure
What does the NORM BRK memo in GREEN or AMBER mean?
GREEN = Auto and Alternate brakes failure and normal braking is still available
AMBER = Loss of Normal Braking from BSCU failure or low GREEN HYD pressure
What does the ALTN BRK memo mean when in GREEN or AMBER?
GREEN = Alternate braking available, normal and anti-skid failure
AMBER = Alternate braking failure
How are the Landing Gear Position indicators being signaled?
By LGCIU 1 only
When would you use MAX autobrake?
Only for take-off
What happens, technically, when you set the A/SKID & N/W STEERING switch to ON?
Power is provided to the dual channel BSCU
Which HYD system powers the parking brake?
The YELLOW HYD system
What HYD system powers the wheel brakes normally?
The GREEN HYD system
When is normal braking available?
When GREEN HYD pressure is available
At least one BSCU is working
Will anti-skid work in Alternate braking mode?
Depends on the failure…
If there is low HYD pressure in the GREEN system it will work
It will not work when using Accumulator only or when the BSCU is faulty
How long can the parking brake be used with accumulator pressure?
12h
How many brake applications will the accumulator give?
7 full applications
How can you charge the YELLOW HYD system in order to make the parking brake work?
By enegizing the YELLOW electrical HYD pump
What is the tripple brake gauge showing?
Parking brake pressure from the YELLOW HYD system
What two systems are essential to have during an aborted T/O?
Auto brakes and Spoilers
When will autobrake engage during a rejected take-off?
When spoilers are activated
Thrust is at idle
What is the steering limit of the rudder pedals?
6 deg in either direction that gradually decreases to 0 from 40 knots to 130 kts
How does AUTO/BK LO work?
Activates 4 seconds after spoiler extension with 1,7 m/sec deceleration
How does AUTO/BK MED work?
Activates 2 seconds after spoiler extension with 3 m/sec deceleration
When will the DECEL light illuminate?
When braking action is 80% of target rate
How can you deactivate auto brakes?
- Turn off the AUTO/BK pb
- Apply pressure to at least one brake pedal (both for MAX)
- Retract ground spoilers
When do you have to call maintenance in regards to high brake temperatures?
When the temp of any brake is over 600 deg C and when the difference between two brakes on the same gear is more than 150 deg C.
Also when temp is below 60 deg C
Will you have auto brake with the Alternate Brake system?
No, only with the NORMAL SYSTEM
When would Accumulator only braking be used?
When there is low GREEN and YELLOW HYD pressure
When would the RED arrow next to the Gear selector illuminate?
Gear not down and locked by 750 feet AGL
Why would recycling the gear possibly help a gear problem?
Recycling the gear forces the other LGCIU to operate
What other systems would be inoperative with the loss of both LGCIU:s?
Thrust reversers and GPWS
What systems are lost with failure of both BSCU:s?
- Nose wheel steering
- Normal braking
- Anti skid
- Auto brakes
How is gravity extension achived? And what happens to the gear doors?
When you turn the crank it isolates the landing gear hydraulics from the GREEN HYD system. Unlocks the landing gear doors and main and nose gears to allow gravity to drop the gear down into the extend position. The gear doors remains open for the rest of the flight
On the GEAR panel, what is indicated by a red UNLK light? What is the source of this indication?
UNLK (red) if gear is not locked in the selected position. Panel is connected to LGCIU 1 and get signals from proximity sensors
How many green triangles is needed to confirm that the gear is locked down?
Only 1
How much N/W Steering is available through the Rudder Pedals and the tiller?
Rudder pedals = +- 6 deg
Tiller = +- 75 deg
What happens when the button on the tiller is pressed?
It removes control of the nose wheel steering from the rudder pedals. Used to perform rudder pedal control check
When ECAM gives message “L/G - GRVTY EXTN”, what should you do?
Use QRH and use following procedure: Crank must be turned approximately 3 times. Once gear is down, select lever to down to lock position
What is indicated by vertical amber lines on each side of a wheel number on the SD?
Brake release fault
With HOT brakes indicated, when can you depart again?
Temp must be below 300 deg C without brake fans or 150 deg C if brake fans are installed
What is the maximum brake pressure if ANTI-SKID is inoperative?
1000 psi
The anti-skid de-activates at what ground speed?
20 kts
What are the system requirements needed to arm the auto brake system?
GREEN HYD pressure is available
Anti-skid is available
No failures in the braking system
What is the max speed for Landing Gear operation? (Vlo)
260 kts
What will happen when you switch off the A/SKID & NW STRG switch?
Nose wheel steering is lost
Anti-skid is deactivated
YELLOW HYD system supplies the brakes
After touchdown, what triggers the AUTO/BRK system?
Spoiler extension
What does the NW STRG DISC memo on the E/WD mean?
The nose wheel steering has been disconnected by ground personel
What HYD system powers the landing gear and the doors?
The GREEN HYD system
Is normal hydraulic power available to the gear after emergency gear gravity extension?
No
What happens if speed is 280 kts and you select the landing gear to the down position?
A safety valve shuts off hydraulic power to the landing gear system when speed is above 260 kts
What controls the landing gear lights?
LGCIU 1
What controls and manages all braking functions?
Brake and Steering Control Unit (BSCU)
How is the parking brake system activated when you turn ON the parking brake switch?
Electrically activated. No need to depress the toe brakes
How do you verify that the parking brake is set?
ECAM PARKING BRK memo
Tripple indicator brake pressure is shown
If during a start with parking brake ON, the plane starts to move. What are your actions?
Release the parking brake to restore normal braking with the pedals. With parking brake set to ON, all other brake systems are de-activated
If LGCIU 1 fails, will the lights for the landing gear still work?
No
What causes MAX AUTO BRK to activate during an RTO?
Airspeed above 72 kts
Thrust lever set to idle
Ground spoilers extended
What is the limitation for take-off with regard to brake temperature?
300 deg C
When will the “HOT” indication on the Brake Fan push-button come on?
When the temperature is over 300 deg C
How do you disengage autobrakes?
By pushing on the toe brakes. You can also do it by pushing the autobreak pushbutton.
How do you manually transfer from the NORMAL BRAKE SYSTEM to the ALTERNATE BRAKE SYSTEM?
By selecting the A/SKID & N/W STRG switch to OFF
If anti-skid is inoperative, will you have AUTOBRAKE?
No
What is meant by “in-flight braking”, what triggers it?
It stops the wheel from spinning before going into the wheel well.
Is triggered by gear lever moved from the down position to the up position
Is NORMAL BRAKING available with the BSCU inoperative?
No
When will anti-skid work when using the ALTERNATE BRAKING SYSTEM?
Only when there’s a GREEN HYD SYS LO PRESS situation. If the ALTERNATE BRAKING is operating due to a BSCU failure, then no anti-skid is available as the anti-skid computation happens inside the BSCU
What does ABCU stand for in the braking system?
ALTERNATE BRAKING CONTROL UNIT
What inputs controls the NORMAL BRAKE SERVO VALVE?
Gets a control current from the BSCU based on Antiskid computation. The antiskid computation in turn is based on the autobrake mode selected or the manual brake pressure on the pedals
What is the anti-skid computation based upon?
The antiskid computation is based on the autobrake mode selected or the manual brake pressure on the pedals. Signal is sent from the BSCU to the Servo Valve which regulates the pressure
What is the purpose of the Hydraulic fuse in the braking system?
If it senes a leak, it closes off the flow to that brake so that not all hydraulic fluid is lost through that brake line
Describe the correct procedure for setting the parking brake after coming to a gate?
- Press brake pedals and stop aircraft
- Set parking brake with brake pedals pressed
- Check brake pressure on tripple indicator is above green band
and only then release the parking brake
If Auto Brake brings the aircraft to a complete stop like on a RTO, how can you disarm them before you start to taxi?
By disarming the spoilers. If you don’t do that you can’t taxi
Why could the DECEL light not come on when using auto brake on a wet or contaminated runway?
Cause anti-skid might be modulating the brake action to be below the 80% braking action threshold needed to trigger the light
If braking fails on roll out, what can you do to try to brake the aircraft?
Turn the Nose Wheel Steering switch to OFF as this will change braking from the Normal (Green) to the Alternate (Yellow) system
What happens to the SD when the Gear is extended on Final Approach?
Wheel page appears.
