A&P Inspection, Repair & Overhaul Procedures 5

Question 1

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

Accepted Answer

Surface (uniform) corrosion

Answer

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

Question 2

Exfoliation corrosion is a severe form of which corrosion type?

Accepted Answer

Intergranular corrosion

Answer

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

Question 3

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

Accepted Answer

Steel wool or a steel wire brush

Answer

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

Question 4

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

Accepted Answer

2 rivet diameters

Answer

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

Question 5

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

Accepted Answer

1.5 D wide and 0.5 D high

Answer

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

A&P - Certified Aircraft Mechanic Practice Test