Brakes Flashcards
What is brake by wire?
A signal is sent from the brake control (BCU) to the 4 brake control valves.
How is braking controlled?
Electrically controlled and hydraulically actuated
Which brakes do the hydraulic systems supply?
1 and 4 - hydraulic system 1
2 and 3 - hydraulic system 2
What is the power source for the outboard and inboard brakes?
1 and 4 - ess. DC 1
2 and 3 - ess. DC 2
What is gear retraction braking?
The BCU applies the brakes to stop rotation of the main gear wheels.
How is the nose wheel rotation stopped?
A snubber in the nose wheel compartment.
What is the touchdown protection system?
Touchdown +3 seconds
50kts wheel speed
1 switch can fail
What is the leak protection system?
It closes the shutoff valves below 1500psi
What is the anti skid system?
4 signals, if one falls below average pressure is reduced on that side.
Deactivated below 10 kts
What is locked wheel protection?
Above 30kts
1 wheel 30% lower than the others pressure is reduced on that wheel.
Below 30kts it’s deactivated.
If the plane thinks it’s in the air what brakes do we have?
Emergency braking below 10 kts.
What system supplies the emergency brakes?
Hydraulic system 2
How long will the accumulator supply brake pressure?
24 hours or
6 emergency actuations
Hydroplanning speed.
EP 109kts
LR 113kts
