Practice Test GeeksA&P - Aircraft and Powerplant Certification Practice Test
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Aircraft Fuel Systems Flashcards

6 cards from real A&P practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 6 Aircraft Fuel Systems flashcards as text

  1. What is the purpose of a fuel system boost pump on a reciprocating engine aircraft?

    Answer: To provide fuel pressure for starting and as a backup if the engine-driven pump fails

    Electric boost pumps prime the fuel system for starting and serve as an emergency backup if the engine-driven mechanical fuel pump fails in flight.

  2. Which grade of aviation gasoline (AVGAS) is dyed blue and used in most current general aviation piston aircraft?

    Answer: 100LL (Low Lead)

    100LL (100 Low Lead) AVGAS is dyed blue and is the standard fuel for most piston-powered general aviation aircraft in the United States.

  3. What is the primary reason fuel sumps must be drained during preflight inspection?

    Answer: To check for and remove water and sediment that accumulate at the lowest points of the fuel system

    Water and contaminants are denser than fuel and settle at the lowest points (sumps), so draining removes these before flight to prevent engine fuel starvation.

  4. What does a fuel crossfeed valve allow on a multi-engine aircraft?

    Answer: It allows fuel from one wing tank to feed the engine on the opposite wing

    A crossfeed valve allows either engine to draw fuel from either wing tank, enabling the crew to feed both engines from one tank or maintain fuel balance.

  5. What is the function of a fuel system vent?

    Answer: To equalize tank pressure with ambient air pressure, preventing collapse or structural damage during fuel consumption and temperature changes

    Fuel tank vents prevent a vacuum or pressure differential from forming as fuel is consumed or temperature changes, which could collapse the tank walls or prevent fuel flow to the engine.

  6. What color is Jet-A turbine fuel, and how does its ignition temperature compare to AVGAS?

    Answer: Clear to straw-yellow; Jet-A has a higher flash point (less volatile) than AVGAS

    Jet-A is colorless to straw-yellow and has a flash point of approximately 100°F (38°C), which is significantly higher than AVGAS's flash point of about −50°F (−46°C), making Jet-A less volatile.