Airframe Mechanic Airframe Inspection Questions and Answers — Questions and Answers
Question 1: According to 14 CFR Part 43, which of the following is authorized to perform an annual inspection and approve an aircraft for return to service?
- Any certificated Airframe and Powerplant (A&P) mechanic.
- An A&P mechanic holding an Inspection Authorization (IA). (Correct answer)
- The aircraft owner, provided they hold at least a private pilot certificate.
- An A&P mechanic with at least 10 years of experience on the specific aircraft type.
Correct answer: An A&P mechanic holding an Inspection Authorization (IA).
14 CFR Part 43 specifies the performance standards and authorized persons for maintenance. While an A&P mechanic can perform a 100-hour inspection, only an A&P with a separate Inspection Authorization (IA), a certified repair station, or the aircraft manufacturer can perform an annual inspection and approve the aircraft for return to service.
Question 2: A technician needs to inspect an aluminum wing spar for suspected subsurface cracks that are not open to the surface. Which Non-Destructive Testing (NDT) method is most suitable for this task?
- Dye Penetrant Inspection
- Magnetic Particle Inspection
- Eddy Current Inspection (Correct answer)
- Visual Tap Test
Correct answer: Eddy Current Inspection
Eddy Current Inspection uses electromagnetic induction to detect discontinuities in conductive materials. It is highly effective for finding surface and near-surface cracks, even when they are filled with debris or under paint, and is ideal for subsurface flaws in non-ferromagnetic metals like aluminum. Dye penetrant only works on surface-breaking flaws, and magnetic particle is for ferromagnetic materials.
Question 3: During a pre-purchase inspection, a mechanic is reviewing the aircraft's maintenance records. Which of the following is true regarding Airworthiness Directives (ADs)?
- Compliance with an applicable AD is mandatory and must be documented in the maintenance records. (Correct answer)
- Compliance is at the discretion of the aircraft owner, based on the cost of the required action.
- ADs are recommendations from the manufacturer, similar to Service Bulletins.
- An AD only needs to be complied with during an annual inspection, not a 100-hour inspection.
Correct answer: Compliance with an applicable AD is mandatory and must be documented in the maintenance records.
Airworthiness Directives (ADs) are legally enforceable regulations issued by the FAA under 14 CFR Part 39 to correct an unsafe condition. Compliance with all applicable ADs is mandatory for an aircraft to be considered airworthy, and this compliance must be properly recorded in the maintenance logs.
Question 4: While performing a tap test on a composite honeycomb control surface, an inspector notes a distinct change in sound from a sharp, ringing noise to a dull thud in a localized area. This sound change most likely indicates:
- A properly bonded and solid internal structure.
- A surface scratch that has penetrated the top layer of paint.
- Delamination or a disbond between the skin and the core. (Correct answer)
- Normal variation in sound due to an internal rib or spar.
Correct answer: Delamination or a disbond between the skin and the core.
A tap test relies on acoustic feedback. A well-bonded, solid structure produces a clear, ringing sound. A dull, dead, or "thud" sound indicates a void or separation, such as a delamination or disbond, which absorbs the sound energy instead of transmitting it.
Question 5: An inspector observes fine, dark, soot-like trails extending aft from several rivet heads on the fuselage skin. What is this condition commonly called and what does it indicate?
- Filiform corrosion, indicating a failure of the paint or primer.
- Rivet shear, indicating the rivet has failed and must be replaced immediately.
- A "smoking rivet," indicating movement and fretting in the joint. (Correct answer)
- Intergranular corrosion, indicating an improper heat treatment of the aluminum sheet.
Correct answer: A "smoking rivet," indicating movement and fretting in the joint.
The dark, soot-like trail is aluminum oxide powder that has been forced out of the joint by movement. This condition, known as a "smoking rivet," is a sign of looseness and fretting (microscopic rubbing) between the rivet and the skin, which can compromise the integrity of the joint.
Question 6: An aircraft used for commercial flight instruction requires a 100-hour inspection. According to 14 CFR 91.409, by how much time may this inspection interval be exceeded if the aircraft is being flown to a location where the inspection can be performed?
- The inspection interval cannot be exceeded.
- By no more than 10 hours. (Correct answer)
- By 10 percent of the interval (10 hours), but only for non-commercial operations.
- By up to 25 hours with a special flight permit.
Correct answer: By no more than 10 hours.
14 CFR 91.409(b) explicitly states that the 100-hour limitation may be exceeded by not more than 10 hours while en route to a place where the inspection can be performed. The excess time used must be included when calculating the next 100-hour interval.
Airframe Mechanic Airframe Inspection Questions and Answers
According to 14 CFR Part 43, which of the following is authorized to perform an annual inspection and approve an aircraft for return to service?