Inspection, Repair & Overhaul Procedures Flashcards

Which form of corrosion appears as white or gray powdery deposits on aluminum surfaces?

Answer: Surface (uniform) corrosion

Aluminum corrosion products typically form a white to gray powder on the surface.

Exfoliation corrosion is a severe form of which corrosion type?

Answer: Intergranular corrosion

Exfoliation is intergranular corrosion that lifts metal layers along elongated grain boundaries, often in extruded material.

Before removing corrosion from a clad aluminum skin, a mechanic should avoid which tool?

Answer: Steel wool or a steel wire brush

Steel particles embed in aluminum and cause galvanic corrosion, so steel wool and brushes must not be used.

When inspecting a sheet metal repair, the minimum edge distance for a single-row rivet layout is generally:

Answer: 2 rivet diameters

AC 43.13-1B recommends a minimum edge distance of 2D (2.5D for countersunk) from the rivet center to the sheet edge.

A properly formed shop head on a solid aluminum rivet should be approximately:

Answer: 1.5 D wide and 0.5 D high

AC 43.13-1B specifies a bucktail of about 1.5 times the shank diameter wide and 0.5 times high.

What is the purpose of a stop-drill hole at the end of a crack in sheet metal?

Answer: To relieve stress concentration and stop crack propagation

Drilling a small hole at the crack tip distributes stress over a larger radius, preventing further growth.

Which inspection aid lets a mechanic view the interior of an engine cylinder without disassembly?

Answer: Borescope

A borescope is an optical or video probe inserted through spark plug holes to visually inspect cylinder walls and valves.