Navigation General · Compass - Gyro
A gyrocompass differs fundamentally from a magnetic compass in that the gyrocompass:
- APoints to magnetic north
- BSeeks true north and is unaffected by the Earth's magnetic field or onboard magnetism✓ Correct
- CRequires no power
- DCannot be used at sea
Explanation
A gyrocompass uses a fast-spinning gyroscope and the Earth's rotation to settle on the true (geographic) meridian, so it indicates true north and is immune to magnetic variation and deviation. It does require electrical power and a settling period after starting.
Authority: Bowditch (Pub. 9); gyrocompass
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