Fuel Flashcards
Where does APU get fuel?
Right side collector tank…. Fed by by electrical pumps when engine not running. Or by primary ejector pumps when engines running.
How are engines fed fuel?
Primary ejector pumps which are driven by high pressure motive flow supplied by dedicated engine driven fuel pumps.
Purpose of AC pumps and location?
One in each tank. Provide primary engine feed in the event of ejector pump failure. And provide fuel pressure for ground and inflight start.
What are the sub tanks?
Surge tank for wing down or uncoordinated maneuvers. Collected tank.
How does collector tank work?
Located at wing root. Fuel flows from tip to root and into e collector tank. Each tank has baffle and flapper check valves that prevents fuel from draining from collector tank thus ensuring that fuel is always avail.
Venting
Each tank has vents with independent lines and vents into the surge tanks.
How many drains?
Two on each side. One in collector tank area and other near the wing stub to wing junction. At low points to ensure water can be drained.
Types of fuel indications.
Electric fuel quantity
Mechanical fuel quantity
Fuel temp
Fuel low level indication, which is a separate probe.
Primary fuel indication?
AC capacitance type electrical fuel indicating subsystem.
Back up fuel indication?
Magnetic level indicators. Allows dispatch.
Temp required for fuel indication to show green?
Temp indicator will show in green as long as temp is above -37. Below that shows in amber or amber dashes if there is a fault.
Location of temp sensor?
Left tank….
Attitude that can cause starvation
15 degrees nose up or down… Uncoordinated maneuvers or negative g forces.
How many magnetic stick indicators?
Three in each tank.
How does magnetic stick work?
Twist to unlock. Each has a float. It will drop down… Use the indications on the side to refer to book to get load.