FAA Aviation Mechanic General (AMG)Ground Operations and ServicingMedium
A mechanic is tying down a light aircraft outdoors in anticipation of high winds. What is the recommended angle between the tie-down ropes and the ground for wing and tail tie-downs?
- AApproximately 45 degrees from the ground
- BApproximately 60 to 90 degrees from the ground
- CApproximately 30 to 40 degrees from the ground
- DAs close to vertical (90 degrees) as possible for maximum holding force
Show answer & explanationAnswer & explanation
Correct answer: A. Approximately 45 degrees from the ground
Standard mooring practice calls for tie-down ropes to form an angle of approximately 45 degrees between the rope and the ground, balancing horizontal restraint against wind gusts with vertical hold-down force. Angles too shallow or too steep reduce effectiveness against combined lift and side loads.
Why the other options are wrong
- B. Too steep, reduces effective horizontal hold against wind.
- C. Too shallow, provides insufficient vertical restraint.
- D. Near-vertical ropes provide little resistance to horizontal wind forces.
Aircraft Mooring/Tie-Down
Securing an aircraft to ground anchors using ropes at roughly 45-degree angles to resist wind-induced lift and lateral forces.
- Ropes typically run from wing, tail, and nose tie-down rings
- 45-degree angle balances vertical and horizontal restraint
- Chocks and control locks also used in conjunction with tie-downs
Memory trick: 45 degrees splits the difference between up and sideways.