Hydraulic System Flashcards
When is ACMP 3A normally selected ON?
Captain Before Start flow
When is ACMP 3A normally selected OFF?
Captain Parking flow
Each hydraulic system has and EDP and ACMP (T/F).
False
Can hydraulic fluid be transferred between the systems?
No
Which hydraulic ACMP can be powered by the RAT?
3A
Hydraulic system 3 provides which flight controls?
Elevator, Aileron, Rudder
The EDPs normally deliver hydraulic fluid at ____PSI.
3000
The AC powered pumps in hydraulic system 3 include:
3A and 3B
How many hydraulic systems are on the plane?
3 independent systems
What systems use hydraulic power (6)?
Flight controls, spoilers, landing gear, wheel brakes, thrust reversers, nosewheel steering
How many hydraulic pumps are on the aircraft?
2 EDPs, 4 ACMP, 1 PTU
How many electric pumps are used for systems 1 and 2?
1 per system
How long after power up should you wait before any hydraulic pumps should be turned on and why?
3 minutes to allow the flight controls to accomplish their built in PBIT test
What is the primary and back up source of hydraulic pressure for system 3?
Primary ACMP 3A
Backup ACMP 3B
When will the HYD ACMP 1 automatically activate on the ground?
Flaps >0 and groundspeed >50 knots
OR
Flaps >0 and thrust levers set to T/O
When will ACMP 2 automatically activate on the ground?
Flaps >0 and groundspeed >50 knots
OR
Flaps >0 and thrust levers set to T/O
OR
Engine 1 running with parking brake released
OR
Engine 1 start (once N2 reaches 40%) if parking brake has been applied within the last 6 minutes
When does ACMP 2 automatically turn off on the ground?
When parking brake has been set for >6 minutes
When will ACMP 1 and 2 automatically activate in flight?
EDP failure or flaps > 0
Can we disable the EDP by pressing the SYS 1 or SYS 2 ENGINE PUMP SHUTOFF button in?
No
If the SYS 1 or 2 ENG PUMP SHUTOFF button is pushed in, will the respective EDP keep running?
Yes
What happens when pushing in the HYD SYS 1 or SYS 2 ENGINE PUMP SHUTOFF guarded buttons?
Closes the respective hydraulic shutoff valve, isolating the respective EDP from the hydraulic system
What is the PTU?
Power Transfer Unit
How does the PTU work?
Hydraulic pump in hydraulic system 2 driven by a hydraulic motor installed in hydraulic system 1
Will the PTU operate if on the ground in AUTO?
No
The PTU is used to assist in landing gear operation should the right engine (#2) or right EDP fail (T/F).
True
What is the purpose of the PTU?
Assist in landing gear retraction or extension in the event of engine 2 or EDP 2 failure
Does fluid transfer occur between hydraulic systems while using the PTU?
No
The PTU uses hydraulic power from system 1 to provide pressure to system 2 to power normal operation of which system?
Landing gear
What conditions must be met for the PTU to automatically activate during takeoff or landing?
a. Engine 2 or EDP 2 failure
b. Flaps not set to 0, landing gear not up and locked
c. EDP 1 not failed
d. Hydraulic reservoir 2 > 12%
Why is there a PTU when ACMP 2 acts as the backup for EDP 2?
PTU assists to retract the landing gear because ACMP 2 has lower flow rate than EDP 2
What is the primary purpose of ACMP 3A?
Backup for the primary flight controls
Why does hydraulic ACMP 3A have an ON position
ACMP is the primary pump for system 3 and has no automation
Why does hydraulic ACMP 3B have an AUTO position?
ACMP 3B is back up for ACMP 3A and automatically activates if ACMP 3A fails when the selector knob is in AUTO
What is the purpose of the hydraulic ACMP 1 and 2?
Used as back up for the respective EDP
Why does the selector knob for hydraulic systems 1 and 2 ELEC PUMPs have an ON position?
To override the system and turn the respective pump on
Which ACMPs are automatically switched on for takeoff and landing?
ACMP 1 and 2
If both engines fail, what provides hydraulic pressure to the flight controls until the RAT comes on line?
Hydraulic 3 accumulator
After 8 seconds, the RAT will power ACMP 3A
If both engines fail, what provides hydraulic pressure to the flight controls after the RAT comes on line?
3A ACMP
What ACMP will function if the RAT is the only power source?
ACMP 3A
Using RAT power, if ACMP 3A fails, will ACMP 3B operate?
No, ACMP 3B is not powered by the RAT
What items are on HYD system 1?
Lefthand outboard elevator Upper rudder Lefthand thrust reverser Multifunction spoilers 3 and 4 Ground spoiler 2 Outboard brake
What items are on HYD system 2 (6)?
Left and righthand inboard elevator Left and righthand inboard aileron Righthand thrust reverser Multifunction spoiler 5 Ground spoiler 1 Inboard brakes
What items operate on HYD system 3?
Righthand outboard elevator
Lower rudder
Lefthand and righthand outboard aileron
When must a hydraulic warm-up be accomplished?
First flight of day with temperatures -18° or less
