Airframe Mechanic Certification Sheet Metal Structures 5

Question 1

A cracked sheet metal skin panel that extends to within one rivet pitch of a stringer attachment must be repaired by:

Accepted Answer

Replacing the damaged skin section and using the stringer as part of the repair boundary

Answer

When a crack extends near structural members, the repair design must incorporate those members as boundaries and cannot rely on stop-drilling alone.

Question 2

What information is found on a sheet metal part's material callout such as '2024-T3 ALCLAD .040'?

Accepted Answer

Alloy, temper, cladding type, and sheet thickness in inches

Answer

The callout '2024-T3 ALCLAD .040' specifies the aluminum alloy (2024), temper (T3), that it has alclad corrosion-resistant cladding, and the sheet thickness is 0.040 inches.

Question 3

When inspecting a riveted skin splice for serviceability, which condition would require immediate repair?

Accepted Answer

A crack emanating from a rivet hole

Answer

A crack emanating from a rivet hole is a critical defect that requires immediate repair because it will grow under fatigue loading.

Question 4

The 'neutral axis' of a sheet metal bend is important because:

Accepted Answer

It is the layer that experiences neither compression nor tension and has no change in length

Answer

The neutral axis is the theoretical line within the material that is neither stretched nor compressed during bending, and its location determines bend allowance.

Question 5

Which rivet installation defect is called a 'clinched' rivet?

Accepted Answer

A rivet whose shank has bent over instead of forming a proper shop head

Answer

A clinched rivet occurs when the shank bends sideways rather than mushrooming outward, resulting in a bent shank and poor joint quality.

Airframe Mechanic Certification Practice Test

Airframe Mechanic Certification Practice Test

Airframe Mechanic Certification Sheet Metal Structures 5