Airframe Mechanic Certification Aircraft Structures 4

Question 1

What is the primary advantage of a composite sandwich structure (face sheets with honeycomb core) over solid aluminum sheet?

Accepted Answer

High stiffness-to-weight ratio with excellent bending resistance

Answer

Sandwich construction provides exceptional bending stiffness relative to weight by placing strong face sheets far from the neutral axis, separated by a lightweight core.

Question 2

During a pressurized aircraft's service life, the fuselage skin experiences repeated pressurization cycles. What fatigue mechanism is primarily responsible for eventual skin cracking?

Accepted Answer

Low-cycle fatigue from pressurization/depressurization

Answer

Each flight cycle applies one pressurization/depressurization event, constituting low-cycle fatigue that drives crack initiation and propagation in fuselage skin.

Question 3

A wing rib's primary structural function is to:

Accepted Answer

Maintain the airfoil shape and transfer loads to the spar

Answer

Ribs define and maintain the wing's airfoil cross-section and transfer chordwise aerodynamic loads to the wing spars.

Question 4

What is the term for an approved repair that deviates from the original design but restores the structure to an equivalent level of airworthiness?

Accepted Answer

Alternate means of compliance (AMOC)

Answer

An Alternate Means of Compliance (AMOC) is FAA-approved authorization to use a method, standard, or practice different from that prescribed while still meeting airworthiness requirements.

Question 5

In a multi-spar wing, what is the primary function of the front spar compared to the rear spar?

Accepted Answer

The front spar carries most bending loads; the rear spar supports control surfaces and fuel

Answer

In most designs the front spar carries the majority of bending and shear from lift, while the rear spar provides attachment for trailing-edge control surfaces and closes the torsion box.

Airframe Mechanic Certification Practice Test

Airframe Mechanic Certification Practice Test

Airframe Mechanic Certification Aircraft Structures 4