31. Forward Instrument Panel (Landing Gear) [O] Flashcards
What is the function of the two Landing Gear Control and Interface Units (LGCIUs)?
• Provide sequencing, operation, monitoring, and indications for the landing gear.
• Provide aircraft “In Flight” or “On the Ground” signals to other aircraft systems
What hydraulic system powers the landing gear and doors?
Green
When does the red arrow in the LND panel illuminate?
Below 750 feet RA, when the aircraft is in the landing configuration and the landing gear is not locked down
What happens if airspeed is 280 knots and the Landing Gear lever is selected DOWN?
Nothing. A safety valve shuts off hydraulic power to the landing gear system when airspeed is above 260 knots
What do the red UNLK lights indicate?
The landing gear is not locked in the selected position.
If LGCIU 1 fails will the lights still work?
Yes, as long as it is still powered.
What controls and manages all normal braking functions?
The Brake and Steering Control Unit (BSCU)
What happens when the A/SKID & N/W STRG is switched OFF?
• Loss of nose wheel steering
• Braking is powered by the YELLOW system
• Anti-skid is deactivated
• ABCU takes over
Which hydraulic systems provide pressure to the brakes?
• Normal brakes – GREEN
• Alternate brakes – YELLOW backed up by a hydraulic accumulator
When do the Auto Brakes activate on landing if armed?
When the ground spoilers deploy.
What is the difference between LOW and MED AUTO BRK?
• LOW – progressive pressure applied to brakes 4 seconds after ground spoilers deploy in order to decelerate the aircraft at a rate of 5.6 ft./s2
• MED – progressive pressure applied to brakes 2 seconds after ground spoilers deploy in order to decelerate the aircraft at a rate of 9.8 ft./s2
What does the AUTO BRK green DECEL light indicate?
Actual rate of deceleration is within 80% of the selected rate.
What will cause the MAX AUTO BRK to activate on a rejected takeoff?
• Airspeed above 72 knots, and
• Thrust levers at IDLE, and
• Ground spoiler extension
What is the impact of the loss of GREEN hydraulic pressure on the Auto Brakes?
The Auto Brake function is lost, because the aircraft is now relying on the alternate brake system.
If on the alternate brake system, what is required in order to maintain Antiskid function, if anything?
At least 1 channel of the BSCU
