Fuel system Flashcards
Where is the fuel stored?
Two integral wing tanks
How many pumps are found in each tank and what are they called?
Three; one ejector pump, one scavenge ejector pump, one electric fuel boost pump.
What is normally used to supply fuel from the wing to the engine fuel control unit in flight?
Ejector pumps.
How is the primary fuel ejector pump powered?
Motive flow from the respective engine.
What is the primary purpose of the scavenge jet pump?
Maintains the fuel level in the collector tank ensuring a constant flow of fuel to the engine during normal flight.
When is the electric fuel pump activated if in the auto position?
Engine start, crossfeed operation, lo press, if primary ejector pump fails.
What ensures that the differential pressure between the tank and ambient remains within structural limits and prevents fuel spillage?
A vent system including a NACA air inlet/outlet.
How is crossfeeding performed?
Select the XFEED switch to the wing tank with the low fuel quantity
(LO 1 or LO 2). This opens the XFEED valve and turns on the electric DC pump in the wing tank with the highest level of fuel. Both engines will utilize fuel from that tank.
What is the restriction on crossfeed operation?
Shall not be performed during takeoff and landing.
When fuel becomes balanced and the XFEED valve is still open, what CAS message will be annunciated?
“FUEL EQUAL”.
Will the total tank quantity indication be lost if only one wing tank quantity indicator fails?
Yes
The fuel shutoff valves are normally open. What is the only way to close one of these valves?
By pushing the fire shutoff pushbutton.
What would cause a “FUEL LO LEVEL” CAS message?
310 lbs of fuel remaining in the respective tank.
What would cause a “FUEL IMBALANCE” CAS message?
220 lbs imbalance.
Is there de-fueling capability?
Yes, by means of a dump valve located under each wing.
While fueling, what monitors the fuel quantity in the tanks and controls refueling flow into each tank?
EFCU, Electronic Fuel Control Unit.
How long is maximum refueling time from empty to full?
Less than 12 min, at 50 psig.
Explain the two critical tests that should be accomplished on the control panel before re-fueling begins?
Lamp Test – When the LAMP TEST switch is held up, the LH TANK and RH TANK indicator lights stay on or come on according to the status of these lights, the FAIL indicator light turns on and the digits light up.
Shut-Off Test – When the SHUT-OFF TEST switch is held up during pressure refueling operation, the LH TANK and RH TANK indicator lights must come on, indicating that the shut-off valve closes, and the FAIL indicator light must be off.
What action is necessary to accomplish on the refueling panel if external power is not being utilized?
The POWER SWITCH must be selected to BATT.
