Do fighter jets have a traditional inverted fuel system?

falstro
  • Do fighter jets have a traditional inverted fuel system? falstro

    Common solutions for aerobatic piston singles is to have either header tanks (for wing tanks, as I understand it) or flop tubes (for fuselage tanks). Do fuel systems in a fighter jet work on the same principles? Or are they somehow smarter to allow more erratic maneuvers?

  • I don't know for certain as I'm not military, but I imagine that they pressurize the fuel tanks using bleed air, much like jet airliners do. It's also likely that they make use of boost and ejector pumps to provide positive pressure directly to more centrally-located tanks which the engines then feed from.

    enter image description here (from FAA AMT Handbook [pdf])

    The F-15 has both wing & fuselage tanks; according to a site of dubious accuracy (F-15E.info):

    The left and right engine feed tanks contain baffles in order to provide a limited amount of fuel to the boost pumps during inverted flight or during negative G maneuvers

    enter image description here

    1. Left wing tank
    2. Auxiliary tank
    3. Left engine feed tank
    4. Right wing tank
    5. Right engine feed tank
    6. Tank 1 (main tank)

    Baffles are dividers in the tank itself that limit the speed at which fuel can flow from one end to another, usually to prevent fuel sloshing and screwing up balance.

Related questions and answers
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  • Common solutions for aerobatic piston singles is to have either header tanks (for wing tanks, as I understand it) or flop tubes (for fuselage tanks). Do fuel systems in a fighter jet work on the same principles? Or are they somehow smarter to allow more erratic maneuvers?

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