Ad
related to: how to take a compass bearing
Search results
Results From The WOW.Com Content Network
An old bearing compass. All hand compasses can be used to take bearings, but what distinguishes the bearing compass from the rest is the fact that it has some type of optics to allow viewing "at the same time" the compass marks and the observed target.
A compass rose, showing absolute bearings in degrees. In nautical navigation the absolute bearing is the clockwise angle between north and an object observed from the vessel. If the north used as reference is the true geographical north then the bearing is a true bearing whereas if the reference used is magnetic north then the bearing is a ...
The resulting bearing indicated is the magnetic bearing to the target. Again, if one is using "true" or map bearings, and the compass does not have preset, pre-adjusted declination, one must additionally add or subtract magnetic declination to convert the magnetic bearing into a true bearing. The exact value of the magnetic declination is place ...
Floating-card compass with prismatic sight (bearing 220° through eyepiece). The marine hand compass, or hand bearing compass|hand-bearing compass as it is termed in nautical use, has been used by small-boat or inshore sailors since at least the 1920s to keep a running course or to record precise bearings to landmarks on shore in order to determine position via the resection technique.
In marine navigation, a pelorus is a reference tool for maintaining bearing of a vessel at sea. It is a "simplified compass" without a directive element, suitably mounted and provided with vanes to permit observation of relative bearings. [1] The instrument was named for one Pelorus, said to have been the pilot for Hannibal, circa 203 BC.
Compass surveying is a type of surveying in which the directions of surveying lines are determined with a magnetic compass, and the length of the surveying lines are measured with a tape or chain or laser range finder. [2] The compass is generally used to run a traverse line. The compass calculates bearings of lines with respect to magnetic needle.
A bearing is a measure of the direction to an object. [17] If the navigator measures the direction in real life, the angle can then be drawn on a nautical chart and the navigator will be somewhere on that bearing line on the chart. [17] In addition to bearings, navigators also often measure distances to objects. [16]
A bearing compass is a magnetic compass mounted in such a way that it allows the taking of bearings of objects by aligning them with the lubber line of the bearing compass. [79] A surveyor's compass is a specialized compass made to accurately measure heading of landmarks and measure horizontal angles to help with map making .