Compass Swing Procedure

The “Compass Swing Procedure” is the official name for the process described.

🧭 Compass Swing Procedure – Simple Definition

It’s the testing and adjustment procedure used to:

1. Measure the deviation (error) of the aircraft’s magnetic compass,
2. Compensate it using adjustment magnets, and
3. Calibrate it by recording the remaining deviation on a compass deviation card.

⚙️ What Happens During a Compass Swing

1. The aircraft is parked on a compass base (a special area with a painted compass rose).
2. It’s aligned on known headings (e.g. 0°, 30°, 60°, etc.).
3. The aircraft’s compass reading is compared with an accurate reference compass.
4. Small compensation magnets in the compass are adjusted to reduce the errors.
5. Any remaining error is recorded on the deviation card (this is the calibration step).

✈️ In short:

The Compass Swing Procedure is the full process of checking, adjusting, and recording compass deviation to make sure the aircraft’s magnetic compass gives an accurate heading in flight.

Perfect 👍 — here’s a simple and clear explanation of those three related terms:

🧭 Compass Swing, Calibration, and Compensation

🔹 1️⃣ Compass Swing

• A test procedure to find out how much deviation the aircraft’s magnetic compass has.
• The aircraft is turned through different headings (e.g. every 30°) on a compass base (a special area with a painted compass rose).
• The aircraft’s compass readings are compared with a reference compass that’s known to be accurate.
• This shows how much the aircraft’s magnetic field affects the compass.

🧠 Purpose: To measure compass errors (deviation) caused by aircraft materials, electrical systems, and magnetism.

🔹 2️⃣ Compass Calibration

• Once the deviation is measured during the swing, the results are written on a deviation card (mounted near the compass).
• The pilot uses this card to correct the compass reading in flight.

🧮 Example: If on heading 090°, the deviation is +2°, → the real heading = compass reading − 2° = 088°.

🧠 Purpose: To record and apply corrections for compass deviation.

🔹 3️⃣ Compass Compensation

• Adjustment made using small magnets or screws near the compass to reduce the deviation as much as possible.
• After compensation, a new compass swing and calibration are done to verify accuracy.

🧠 Purpose: To physically correct magnetic errors in the aircraft so the compass is more accurate.

✅ In short:

✈️ Simplified Summary:

You swing the aircraft to find compass errors, compensate to reduce them, and calibrate to record what remains.