A&P A&P - Aircraft and Powerplant Aircraft Fuel Systems

Question 1

What grade of aviation gasoline (avgas) is identified by its blue color?

Accepted Answer

100LL (low-lead)

Answer

80/87

Answer

100/130

Answer

115/145

Question 2

What is the primary purpose of a fuel system boost pump?

Accepted Answer

Provide positive fuel pressure to the engine-driven pump and prevent vapor lock

Answer

Replace the engine-driven pump during normal cruise

Answer

Filter water from the fuel before engine combustion

Answer

Pressurize the fuel tanks during high-altitude flight

Question 3

What does a fuel selector valve set to 'BOTH' mean on a single-engine aircraft with two wing tanks?

Accepted Answer

Fuel is drawn from both tanks simultaneously through a crossfeed manifold

Answer

Both tanks are isolated to prevent crossfeed

Answer

The left tank feeds only, with the right tank as reserve

Answer

Fuel flows only to the boost pump, not the engine

Question 4

Where is the fuel tank sump drain located and why?

Accepted Answer

At the lowest point of the tank to collect and drain water and sediment

Answer

At the top of the tank to vent vapors

Answer

At the tank outlet to protect the fuel selector valve

Answer

At the fuel cap to allow overflow during refueling

Question 5

What is the maximum allowable water contamination check procedure during aircraft preflight?

Accepted Answer

Drain a sample from each sump into a clear container and visually check for water globules or cloudiness

Answer

Use a fuel tester strip inserted into the fuel cap opening

Answer

Check the fuel color with a UV light for water fluorescence

Answer

Measure fuel specific gravity with a hydrometer

Question 6

What type of fuel does a turbine (jet) engine aircraft use?

Accepted Answer

Jet-A (kerosene-based)

Answer

100LL avgas

Answer

Mogas (automotive gasoline)

Answer

Jet B (wide-cut gasoline blend)