FAA Aviation Mechanic Airframe (AMA)Airframe Electrical and InstrumentsHard
A technician is performing a compass swing on a compass rose. The aircraft is aligned on a magnetic heading of 000° (north) and the N-S compensator screw is adjusted to minimize deviation. On which heading should the technician next align the aircraft to adjust the E-W compensator screw?
- A090° (east)
- B270° (west)
- C045° (northeast)
- D180° (south)
Show answer & explanationAnswer & explanation
Correct answer: A. 090° (east)
During a standard compass swing, the aircraft is first aligned on magnetic north to adjust the N-S compensating magnet, then aligned on magnetic east to adjust the E-W compensating magnet. Remaining headings (south, west, and intercardinal points) are then checked and residual deviation is recorded on the compass correction card.
Why the other options are wrong
- B. West is also a check heading, not the adjustment heading for E-W compensation.
- C. Intercardinal headings are used only for recording deviation, not for compensator adjustment.
- D. South is a check heading afterward, not used to adjust the E-W compensator.
Compass Swing Compensation Sequence
A procedure to minimize magnetic compass deviation by adjusting the N-S compensator on a north heading and the E-W compensator on an east heading, then recording residual deviation on other headings.
- N-S compensator adjusted while heading north
- E-W compensator adjusted while heading east
- Remaining headings are recorded, not adjusted, on the deviation card
Memory trick: North fixes North-South screw, East fixes East-West screw