Hydraulic System Flashcards
What systems are powered by the #1 HYD system?
- centre AP
- nose and body gear actuation and steering
- left elevators
- inboard TE flaps
- some ailerons
- alternate brakes
- upper rudder (with #3)
What systems are powered by the #4 HYD system?
- wing gear actuation
- right elevators
- outboard TE flaps
- some spoilers
- some ailerons
- lower rudder (with #2)
- normal brakes
What systems do HYD #2 and #3 share?
stabilizer trim and yaw dampers
With the loss of HYD #4, do you have auto brakes and anti-skid?
auto brakes- no
anti-skid- yes, in pairs only
What powers the #1 and #4 demand pumps?
Air (it’s faster)
What powers the #2 and #3 demand pumps?
electric (more torque)
Is there a shut off valve for the demand pump?
No, theres a switch but not a valve
When do demand pumps 1 and 4 automatically operate?
flaps in transit or out of up
What conditions will cause the HYD SYS fault light to illuminate?
- low system pressure
- high system temperature
- low reservoir quantity
What conditions will cause the demand pump low PRESS light to illuminate?
- demand pump selector to OFF or AUX
- output pressure is low with pump operating
- demand pump fails to operate
When the demand pump switch is in AUX, why doesn’t the PRESS light extinguish?
because the pressure light is for the demand pump and it isn’t on
