AM Troubleshooting & Diagnostics 2

Question 1

An aircraft engine experiences intermittent power loss only at high altitude. Which system is the most likely cause?

Accepted Answer

Mixture control or fuel metering unit malfunction

Answer

Altitude-related power loss typically indicates a fuel metering or mixture issue since fuel-air ratio requirements change significantly with altitude.

Question 2

During run-up, a magneto drop is 175 RPM on the left magneto and 50 RPM on the right. What does this indicate?

Accepted Answer

The left magneto or its spark plugs have a problem

Answer

An excessive drop on one magneto indicates a fault in that magneto, its leads, or the spark plugs it fires; the right magneto's low drop is normal.

Question 3

A hydraulic actuator moves slower than normal but maintains full travel. Which fault is most likely?

Accepted Answer

Restriction in the hydraulic line or internal bypass/wear

Answer

Slow but full-travel movement suggests a flow restriction or internal leakage allowing the actuator to eventually reach full extension.

Question 4

When troubleshooting an avionics unit that shows no display, the FIRST step per standard procedure is to:

Accepted Answer

Check circuit breakers and power supply to the unit

Answer

Always verify power and circuit breaker status before condemning or removing any avionics unit.

Question 5

An aircraft landing gear indicates 'gear up' in the cockpit but the red warning light remains illuminated. What should be investigated first?

Accepted Answer

Proximity sensor or micro-switch alignment on the gear

Answer

A disagreement between the position indicator and the warning light often points to a misaligned or faulty proximity sensor or limit switch.

(AM) Aircraft Maintenance Certification Practice Test

(AM) Aircraft Maintenance Certification Practice Test

AM Troubleshooting & Diagnostics 2