Landing Gear & Brakes Flashcards
How many weight on wheels sensors are there?
2 on each gear, for a total of 6
What happens if two WOW sensors fail on the same gear?
On ground - LG lever will not move up and LG NO DISPATCH caution message will display
In air - LG lever will not move up, and LG WOW SYS FAIL caution message will display
What does the electrical override system do?
It bypasses the PSEM and extends the gear the same way as normal operation
How does the alternate gear extension work?
Lever releases hydraulic pressure and uplocks, gear free falls
When would you use the down lock release button?
If needed to clear obstacles
When will the gear aural warning sound and not be able to be silenced?
Slats/flaps 5 or full
Slats/flaps 0-4, RA below 700’, TLA below 45° (both engines) or 59° (single engine)
Which hydraulic system do the outboard brakes use?
Hydraulic system 1
Which hydraulic system do the inboard brakes use?
Hydraulic system 2
What does the BCM (brake control module) do?
Locked wheel protection
Anti skid protection
Automatic wheel braking
Touchdown protection
What is locked wheel protection?
Above 30kts the system compares wheel speeds: A difference of 33% causes the slower wheel brake pressure to drop to zero
Below what speed is anti skid protection deactivated?
10kts
What is automatic wheel braking?
Brakes wheels during retraction
What is touchdown protection?
Prevents touchdown with MLG brakes applied. Deactivated above 50kts wheel speed or 3 seconds after WOW sensor detects landing
Which hydraulic system powers the emergency brake?
Hydraulic systems 1 and 2
How many applications will the emergency brake accumulator allow?
6
