Airframe Systems & Components Flashcards

What type of structural damage is indicated when an aircraft skin shows a series of small cracks radiating from a common point?

Answer: Fatigue cracking from cyclic stress

Radiating cracks from a common stress concentration point are classic fatigue cracks caused by repeated cyclic loading.

In an aircraft oxygen system, what color are high-pressure oxygen cylinders required to be painted?

Answer: Green

Aviation oxygen cylinders are painted green to identify them as containing aviator's breathing oxygen.

Which aircraft component is specifically designed to fail first in an overload condition to protect primary structure?

Answer: A fuse pin or shear pin

Fuse pins and shear pins are designed with a calculated failure load so they break first, protecting more critical surrounding structure.

What is the primary purpose of wing washout (geometric twist)?

Answer: To ensure the wing root stalls before the tip to maintain aileron effectiveness

Washout decreases the angle of incidence toward the wingtip so the root stalls first, keeping airflow attached at the tips and ailerons effective.

When performing a repair on a pressurized aircraft skin, the repair doubler must extend at least how many rivet rows beyond the damaged area?

Answer: Two rivet rows

Pressurized skin repairs typically require the doubler to extend at least two rivet rows beyond the damaged area to properly redistribute loads.

What is the function of a spoiler on a large transport-category aircraft during landing?

Answer: To dump lift and increase drag, reducing lift-off tendency and shortening landing roll

Ground spoilers deploy on touchdown to destroy lift, increasing wheel loading for effective braking and shortening the landing roll.

A 'station' number on an aircraft refers to a distance measured from:

Answer: A reference datum, typically forward of or at the nose

Station numbers are distances measured in inches aft of an arbitrary reference datum, usually located at or forward of the nose.