Gyrocompass

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Overview

The heart of a gyrocompass is a heavy gyroscope driven by an electric motor. It is not affected by magnetism or by the pitching of a ship.

When properly mounted, adjusted, and corrected, it will always point to true north, rather than to magnetic north. Electric circuits relay information from the gyroscope to instruments called repeaters in various parts of the ship. These instruments can indicate direction or keep a constant record of the ship's movements.

A gyropilot is a repeater and other equipment coupled with the steering mechanism that keeps the ship on course. Gyropilots are also used to steer torpedoes and some guided missiles.

The gyrocompass must be constantly corrected as the vessel changes course, speed, and latitude. Instruments have been developed that make these corrections automatically.

System components

• Gyro Compass
• Heading Repeater
• Bearing Repeater
• Bearing Sight
• Pelorus Stand
• Multi Display

Carriage requirement

SOLAS Chapter V Reg 19:

• All ships of 500 GT and upwards shall have a gyro compass, or other means, to determine and display their heading by shipborne non-magnetic means, being clearly readable by the helmsman at the main steering position;
  • A gyro compass heading repeater, or other means, to supply heading information visually at the emergency steering position if provided;
  • a gyro compass bearing repeater, or other means, to take bearings, over an arc of the horizon of 360º, using the gyro compass or other means referred to in subparagraph .1. However ships less than 1,600 gross tonnage shall be fitted with such means as far as possible;