Hydraulic System Flashcards
What is the normal operating range for each HYD system?
4600 < 5250 psi
Each HYD system operates at a pressure of approximately _____ psi.
5,000
What 11 components are part of the HYD 3 utility system?
- Engine start system
- EAPS blowers
- Rotor brake
- Cargo ramp/door actuators
- Landing gear actuators
- Wheel brakes
- Nose wheel steering
- Rotor positioning unit
- Wing stow system
- Aerial refueling retractable probe
- Cargo winch
Where are the HYD 1/2 pumps located?
On their respective TAGB
The HYD pumps deliver ___ GPM in VTOL mode and ___ GPM IN APLN.
38
32
How is HYD fluid cooled?
Through the nacelle heat exchanger.
What do the flight control modules do?
Supply low pressure fluid to the pump Store fluid displaced by actuating components Filter pressurized and return fluid Dampen pressure fluctuations Sense and limit system pressure
The temperature switch signals the appropriate FCC to illuminate a caution whenever a HYD system fluid temperature reaches ___ °C.
121
The reservoir has a capacity of ___ cubic inches of HYD fluid.
330
The accumulator has a ___ cubic inch capacity.
12
The relief valve limits the pressure to a maximum of _____ psig.
5,850
The HYD 1/2 pumps pressurize their respective systems at ___ Nr.
58%
The thermal control valves are used to rapidly warm up the hydraulic fluid temperature is below ___ °C
4
HYD 3 is located on and driven by the _____
MWGB
The HYD 3 reservoir has a capacity of ___ cubic inches.
660
HYD 3 fluid is cooled by the _____.
MWGB oil cooler and fan assembly
T/F: the HYD 3 thermal control valves operate the same as the TCVs for HYD 1/2.
True
The utility isolation valve is normally _____ and is automatically energized _____ in flight when the landing gear is up and locked.
Open
Closed
The only time the UTIL key would show a mismatched stated is if the utility valve is _____.
Jammed
The UTIL OPEN/CLOSE key is unavailable when:
- HYD 3 has failed
- HYD 3 is manually selected off
- HYD 3 is backing up a swashplate actuator and the reservoir is less than 150 in^3
- WOW
Flaperon settings are ___ - ___°
0-73
In APLN, the flaperons are limited to ___° up and ___° down
25
40
The maximum flap position displayed on the SFD is ___°.
72
The maximum elevator deflection is ___ up and ___ down.
30°
20°
Maximum rudder deflection is ___ either side of neutral.
20°
HPDU 1/2 drive the _____ ball screw while HPDU 3 drives the _____ ball screw.
Outer
Inner
What does the Nacelle B/U Enable switch do?
Causes HPDU 3 to power each ball screw on each actuator.
Why wouldn’t you be able to rotate the nacelles past 45°?
- WOW
- cabin door is open
When will EAPS switch from AUTO to OFF?
When the NAC B/U is enabled.
The rotor brake is designed to stop the proprotors from ___ in 12 seconds.
40%
In the event of an emergency, the rotor brake will stop the rotors from ___ in 20 seconds.
100%
Draw and label the HYD stat layer.
Done
Explain the leak logic for a HYD 2 leak in a flaperon actuator.
- Leak is detected
- HYD 2 local isolation valve isolates HYD 2 to the right nacelle
- HYD 2 remote switching valve in the left nacelle allows HYD 3 to power the other half of the swashplate actuators.
Explain the leak logic of a HYD 1 leak in the left nacelle swashplate actuator.
- HYD 1 local isolation valve isolates it to the left nacelle
- HYD 1 remote switching valve open up for HYD 3 to power the other swashplate actuator.
- HYD 1 local switching valve switches back to to HYD 1 to prevent HYD 3 from leaking out.
- HYD 1 bleeds out until HYD 1 FAIL and SWPL SINGLE BOOST
Explain the leak logic of a HYD 2 leak in the left nacelle swashplate actuator.
- HYD 2 isolated
- HYD 2 remote switch
- HYD 3 leaks and HYD 2 remote switchback
- Left NAC SWPL SINGLE BOOST
HYD 3 provides _____ psi to the brake master cylinders.
2000
What does the back-up brake system do?
Provides MLG brake pressure when the HYD 3 pump isn’t operating or off.
Ramp and door opening and closing times are approximately ___ seconds.
12
What does a green X mean?
When the AC is on the ground and the system is turned off.
What does a green dot mean?
The actuator boost state, HYD temp, or HYD fluid quantity is unknown or invalid.
What does a white crosshatch patten signify?
A single failure in a triple redundant system.
When will the elevator have a yellow fill?
For a critical or dual actuator failure.
When will HPDU 3 turn yellow?
For an FCC failure.
When will the swashplate actuators have a white crosshatch pattern?
With an FCC failure.
What does red generally indicate?
The complete failure of a system or component.
When is a red X displayed in place of a swashplate actuator system?
That half of the swashplate actuator is not being powered.
When is a red X displayed behind a hydraulic pump?
During a cross channel data link failure between FCCs.
When will a red X be displayed behind the pressure data?
Will there still be a pressure reading available?
With a failed aircraft interface unit and the data becomes invalid.
Yes but the data should be considered invalid.
Flight is prohibited with HYD fluid temp below ___.
18°C
Minimum HYD 3 temperature for engine start is ___.
4°C
Maximum HYD temperature is ___.
121°C
Normal operating temperature is ___.
65°C
Normal operating fluid quantity is ___.
200 cubic inches
