Airframe Mechanic Certification Assembly and Rigging 2 — Questions and Answers
Question 1: When rigging a conventional aircraft control system, what document establishes the correct cable tension values?
- The aircraft's Type Certificate Data Sheet
- The manufacturer's maintenance or service manual (Correct answer)
- FAA Advisory Circular AC 43.13-1B
- The aircraft's weight and balance report
Correct answer: The manufacturer's maintenance or service manual
Cable tension specifications are aircraft-specific and must be obtained from the manufacturer's maintenance or service manual.
Question 2: A turnbuckle barrel is safety-wired using the double-wrap method. After safety wiring, at least how many wraps must be visible around each turnbuckle terminal shank?
- Two wraps
- Three wraps (Correct answer)
- Four wraps
- Six wraps
Correct answer: Three wraps
FAA AC 43.13-1B requires a minimum of three wraps of safety wire around each turnbuckle terminal shank when using the double-wrap method.
Question 3: What is the primary purpose of wash-in and wash-out adjustments on an aircraft wing?
- To adjust wing dihedral angle
- To change wing incidence for weight and balance
- To control the spanwise lift distribution and stall characteristics (Correct answer)
- To align the wing attachment fittings
Correct answer: To control the spanwise lift distribution and stall characteristics
Wash-in (increasing angle of attack toward the tip) and wash-out (decreasing it) control spanwise lift distribution and stall progression.
Question 4: During aileron rigging, the left aileron is found to be 2° high (trailing edge up) and the right aileron is 2° low (trailing edge down) with the control wheel centered. This condition indicates:
- Correct rigging — differential travel is intentional
- A bent or misrigged aileron bellcrank
- The aileron cables have unequal tension (Correct answer)
- The ailerons are improperly balanced
Correct answer: The aileron cables have unequal tension
With the control wheel centered, both ailerons should be in the neutral (faired) position; unequal positions with centered controls indicate unequal cable tension.
Question 5: What tool is used to measure the tension of an aircraft control cable?
- Torque wrench
- Cable tensiometer (Correct answer)
- Micrometer caliper
- Cable tension gauge pliers
Correct answer: Cable tensiometer
A cable tensiometer (such as a T-5 or C-8 type) is the standard tool used to measure control cable tension.
Question 6: When assembling a large transport category aircraft's empennage to the fuselage, the horizontal stabilizer incidence is set by:
- Shimming the leading edge attach fittings
- Adjusting the pitch trim jackscrew range
- Shimming or adjusting the rear spar attach point per maintenance manual data (Correct answer)
- Bending the stabilizer spar caps
Correct answer: Shimming or adjusting the rear spar attach point per maintenance manual data
Horizontal stabilizer incidence is set by shimming or adjusting the rear spar (or leading edge) attach points per the manufacturer's maintenance manual tolerances.
Question 7: A swaged cable terminal is rejected during inspection because it fails the 'slip test.' What does this mean?
- The terminal rotated more than 90° under torque
- The terminal pulled off or slipped from the cable when proof-loaded (Correct answer)
- The swage die left visible marks on the terminal
- The terminal did not meet minimum break strength
Correct answer: The terminal pulled off or slipped from the cable when proof-loaded
The slip test proof-loads the swaged terminal to a specified percentage of cable breaking strength; failure means the terminal slipped off or the cable pulled through.
Airframe Mechanic Certification Assembly and Rigging 2
When rigging a conventional aircraft control system, what document establishes the correct cable tension values?