Installation Techniques Flashcards

When installing AN fittings on aluminum tubing, what is the correct procedure for flaring the tube end?

Answer: Use a double-flare tool to create a 37-degree flare

AN fittings on aluminum tubing require a double-flare at 37 degrees to prevent cracking and provide a leak-free seal.

What is the primary purpose of applying thread-locking compound (such as Loctite) on aircraft fasteners?

Answer: To prevent fasteners from loosening due to vibration

Thread-locking compounds prevent fasteners from backing out due to aircraft vibration and dynamic loads.

During hydraulic line installation, a technician notices the tube is slightly short. What is the correct action?

Answer: Replace the tube with one of correct length

Tubes must be replaced with correctly dimensioned pieces; stretching compromises tube integrity and is not an approved repair.

What is the minimum bend radius typically specified for aircraft rigid tubing to prevent stress concentration?

Answer: Three times the tube outside diameter

A minimum bend radius of three times the tube OD is required to avoid work-hardening and stress cracking.

When installing a bonding jumper to an airframe structure, what surface preparation is required?

Answer: Remove all paint and anodizing from the contact area

Bare metal-to-metal contact is required for effective electrical bonding; paint and anodizing must be removed from the mating surfaces.

Which of the following identifies an incorrectly installed AN bolt in a tension application?

Answer: The bolt shank threads extend through the nut more than three threads

Excessive thread extension beyond the nut (more than three threads) indicates the wrong grip length bolt was used.

When routing aircraft wire bundles, what is the minimum clearance from control cables and moveable surfaces?

Answer: 1/2 inch

Wire bundles must be routed with a minimum 1/2-inch clearance from control cables and movable surfaces to prevent chafing and interference.