Fuel Systems & Hydraulic Systems Inspection Flashcards

According to AC 43.13-1B, what category of fuel leak is defined as moisture or fuel that appears as a wet spot but does not form drops?

Answer: Seep

AC 43.13-1B defines a 'seep' as fuel leakage that appears as a wet spot but does not form dripping drops, representing the lowest-severity leak category.

Which regulation specifically lists fuel filters and strainers as items that must be inspected during an annual inspection?

Answer: 14 CFR Part 43, Appendix D

14 CFR Part 43, Appendix D provides the scope and detail of items to be included in an annual or 100-hour inspection, which includes fuel system components such as filters and strainers.

What is the primary aeronautical purpose of fuel tank venting in aircraft fuel systems?

Answer: To prevent dangerous pressure or vacuum buildup as fuel is consumed and temperatures change

Fuel tank venting prevents dangerous pressure buildup or a vacuum from forming as fuel is consumed and as temperature changes cause fuel volume to expand or contract.

During an annual inspection, an IA finds a fuel selector valve that is stiff and requires significant force to move between positions. What is the correct action?

Answer: Repair or replace the valve before returning the aircraft to service

A fuel selector valve that requires excessive force to operate is a safety hazard that could cause pilot error during an in-flight emergency; it must be repaired or replaced before the aircraft is returned to airworthy service.

Which type of contamination poses the greatest immediate risk of engine stoppage in a piston aircraft fuel system?

Answer: Water contamination

Water contamination is the greatest immediate hazard because even small amounts reaching the carburetor or fuel injectors can cause sudden engine stoppage, making it a direct flight safety threat.

When inspecting flexible fuel hoses during an annual inspection, which condition requires immediate replacement?

Answer: Visible cracks, hardening, or deterioration of the outer cover

Flexible fuel hoses with visible cracks, hardening, or deterioration of the outer cover indicate material breakdown that compromises structural integrity and could lead to fuel leakage or rupture.

An IA discovers dark slime (microbial contamination) in an aircraft's integral fuel tanks during an annual inspection. What is the required action before return to service?

Answer: Clean and treat the tanks per the manufacturer's instructions and applicable ADs

Microbial contamination must be addressed by cleaning the tanks and treating them per the aircraft manufacturer's maintenance procedures and any applicable Airworthiness Directives before the aircraft can be returned to airworthy service.