Assembly and Rigging Flashcards
6 cards from real Airframe Mechanic Certification practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Assembly and Rigging flashcards as text
A technician is inspecting a properly tensioned turnbuckle in a primary flight control system and observes four threads are exposed between the barrel and the cable end fitting. What is the correct course of action?
Answer: Replace the turnbuckle with one of a more appropriate length.
According to standard aircraft maintenance practices (such as those in AC 43.13-1B), no more than three threads should be exposed on either end of a turnbuckle barrel. Exposing four or more threads indicates insufficient thread engagement, which compromises the strength of the connection. The correct action is to use a turnbuckle of the proper length to achieve the correct cable tension while ensuring adequate thread engagement.
What is the primary reason that aircraft maintenance manuals provide a temperature/tension chart for rigging flight control cables?
Answer: To compensate for the different thermal expansion rates of the aluminum airframe and the steel cables.
Aircraft structures, typically made of aluminum alloys, expand and contract at a different rate than the steel control cables when subjected to temperature changes. A temperature/tension chart allows a technician to set the correct cable tension at a given ambient temperature, ensuring that the tension will remain within the specified limits whether the aircraft is on a hot ramp or at high altitude where temperatures are very low.
After an aileron has been repainted, it must be rebalanced. Which of the following is the most critical reason for this procedure?
Answer: To prevent the onset of high-frequency control surface flutter.
Adding paint adds weight to the control surface. If this weight is not distributed correctly relative to the hinge line, it can change the surface's center of gravity. An improperly balanced control surface is highly susceptible to flutter, a rapid and destructive oscillation caused by the interaction of aerodynamic, inertial, and elastic forces, which can lead to catastrophic structural failure.
Before checking the wing dihedral and incidence angles during a rigging check, what is the most critical preparatory step?
Answer: Leveling the aircraft both longitudinally and laterally according to the maintenance manual.
All airframe alignment and rigging measurements must be taken from a specific, known reference plane. The aircraft must first be leveled according to the manufacturer's specific instructions and leveling points (often using a spirit level or plumb bob). Performing these checks on an un-level aircraft will result in inaccurate measurements and improper rigging.
During an inspection of a control cable passing over a pulley, a single broken wire is discovered. According to FAA AC 43.13-1B, what action is required?
Answer: The entire control cable assembly must be replaced.
According to FAA guidance in AC 43.13-1B, any cable assembly that has even one broken wire strand located in a critical fatigue area must be replaced. A critical fatigue area includes any section where the cable runs over a pulley, through a fairlead, or within one foot of a swaged fitting.
In aircraft assembly and maintenance, what is the primary function of a cotter pin when used with a castellated nut?
Answer: To act as a positive locking device to prevent the nut from loosening due to vibration.
A cotter pin is a safetying device used to secure bolts, nuts, and other pins. When used with a castellated nut on a drilled bolt, the pin is passed through the castellations and the hole in the bolt, and its ends are bent. This physically prevents the nut from rotating and loosening, which is critical in high-vibration environments like an aircraft.