Test on Aircraft Plumbing Systems and Flexible Hoses

Question 1: Grommets should be used anytime tubing passes through a hole in the aircraft structure.

A. Ano

B. Ne

Explanation: Grommets should be used anytime the tubing passes through a hole in the aircraft structure.

Question 2: What critical precaution(s) must be observed when deburring the cut end of a tube?

A. Care should be taken to ensure the tubing is not cracked.

B. The wall thickness of the tubing must not be reduced by the deburring process.

C. The deburred end must be immediately polished to a mirror finish.

D. Ensure the deburring tool is lubricated with hydraulic fluid.

Explanation: When deburring the cut end of a tube, care should be taken to prevent the tubing from cracking or its wall thickness from being reduced, as these can weaken the tube. Polishing is mentioned for flaring aluminum alloy tubing, not as a general deburring precaution, and lubrication is not mentioned at all.

Question 3: Is it acceptable for the stripe on a hose to spiral around it after installation?

A. Ano

B. Ne

Explanation: The stripe should not spiral around the hose after installation is completed.

Question 4: Standard AN-type fluid line fittings are identified by a stripe.

A. Ano

B. Ne

Explanation: AN fluid-line-fittings are colored either blue or black. The stripe is used to determine if the hose has twisted during installation, not to identify the fittings themselves.

Question 5: According to the study materials, what is the primary purpose of quick disconnect couplings in fluid systems, specifically related to inspection?

A. To indicate if the hose has twisted during installation

B. To allow for frequent uncoupling of lines for inspection or maintenance

C. To provide color identification for standard AN-type fluid line fittings

D. To prevent the stripe from spiraling around the hose after installation

Explanation: Quick disconnect couplings are installed at locations where frequent uncoupling of the lines is required for inspection or maintenance.