A&P Aircraft Fuel Systems 2

Question 1

What is the hazard of misfueling a piston aircraft with Jet-A fuel instead of 100LL AVGAS?

Accepted Answer

Jet-A will not ignite reliably in a spark-ignition engine, leading to power loss or engine stoppage

Answer

Jet-A's high flash point means it will not vaporize or ignite properly in a spark-ignition piston engine, resulting in power loss, rough running, or engine failure.

Question 2

What is the purpose of a fuel system water separator on a turbine aircraft?

Accepted Answer

To remove free water from the fuel stream before it reaches the engine fuel control unit

Answer

A fuel/water separator removes free (undissolved) water from turbine fuel to prevent fuel control unit damage, ice formation in fuel nozzles, and combustion instability.

Question 3

When must the fuel cap be replaced on an aircraft with an integral (wet wing) fuel tank after servicing?

Accepted Answer

Immediately after fueling; the tank must not be left uncapped for any reason during maintenance breaks

Answer

Fuel caps must be reinstalled and secured immediately after servicing to prevent fuel spillage, contamination, or vapor ignition, and the aircraft must not be left unattended with open fuel caps.

Question 4

What is the purpose of a fuel flow divider (distributor) on a fuel-injected reciprocating engine?

Accepted Answer

To evenly distribute fuel to all individual fuel injector nozzles at equal pressure

Answer

The flow divider (manifold valve or spider) distributes metered fuel equally among all fuel injection nozzles to ensure uniform fuel delivery to each cylinder.

Question 5

What is the significance of fuel quantity gauges being required to read accurately only at EMPTY in FAR Part 23 aircraft?

Accepted Answer

It means gauges are only required to be accurate at the empty indication; readings at other levels may be inaccurate, so preflight fuel verification by visual inspection or dipstick is essential

Answer

FAR 23.1337 requires that fuel gauges read zero at the unusable fuel quantity level; the gauge need not be accurate at higher quantities, making physical verification critical.

A&P - Aircraft and Powerplant Certification Practice Test

A&P - Aircraft and Powerplant Certification Practice Test

A&P Aircraft Fuel Systems 2