A competent and professional deviation survey and compass correction According to the Convention of Safety of Life at Sea (SOLAS) from the International Maritime Organization (IMO), the deviation of a ship’s magnetic compass must be adjusted to a minimum. Some countries’ maritime authorities (flag states) specifically require the deviation to be less than 5°. Our Service Engineer is authorized to perform magnetic Compass correction which ensures that all ship types are offered a competent and professional deviation survey and compass correction, which will bring the deviation down to an insignificant deviation. After the compass correction, the deviation survey is performed and a deviation curve and the deviation table are supplied. It is advisable to alert and warn navigators about unstable views on the Magnetic Compass when ships are sailing on high magnetic widths. These warnings are seen in the following. At high magnetic widths - especially in arctic waters - where the Earth’s Horizontal Magnetic Intensity (H) is weak (H is proportional to cosine to Earth’s magnetic field inclination angle (I)), the ship’s magnetic field (K) can create a powerful and noticeable change in the magnetic compass Position force (H ‘), whereby: • There may be difficulties for the magnetic compass to adjust to a steady course • The deviation can be strongly dominated by the ship’s magnetic field (K) • Or in worst cases: The north direction of the magnetic compass is held in the direction of K, regardless of the course of the ship, which makes the Magnetic Compass display useless. On high magnetic widths, where the magnetic compass positioning force (H ‘) can be very weak, the ship must be steady * on the course: • before making a comparison between the Magnetic Compass course and the Gyrocompass course • before and during a deviation survey • before and during a possible magnet compass correction * It may take quite a while - up to several minutes - before the Magnet Compass sets itself on steady course. Click here to download>>
