elenya
Active member
HI
A quick and easy method, and good enough for a yacht is described below. The only time it will have issues is if you happen to have an offset compass (not on centre line) and significant quantities of iron, or you have an offset iron structure. An aircraft carrier is a prime example.
Pick a distant object, 2 miles is fine, more is better. Take a bearing of the object with the vessel headed on all the cardinal and inter cardinal points (more if you want). Try to let the vessel settle on a heading for a minute at least before taking the bearing. I do this on a calm day so i can steam and stop on each heading, or pull yoursaelf round a mooring buoy with a bridle.
The actual magnetic bearing is the average of the bearings taken and deviation can then be worked out for each heading, and a graph draw up.
hope this helps.
A quick and easy method, and good enough for a yacht is described below. The only time it will have issues is if you happen to have an offset compass (not on centre line) and significant quantities of iron, or you have an offset iron structure. An aircraft carrier is a prime example.
Pick a distant object, 2 miles is fine, more is better. Take a bearing of the object with the vessel headed on all the cardinal and inter cardinal points (more if you want). Try to let the vessel settle on a heading for a minute at least before taking the bearing. I do this on a calm day so i can steam and stop on each heading, or pull yoursaelf round a mooring buoy with a bridle.
The actual magnetic bearing is the average of the bearings taken and deviation can then be worked out for each heading, and a graph draw up.
hope this helps.
