The first version is based upon two range/bearing measurements made from Vessel 1. Each measurement includes the range in nautical miles and the true bearing in decimal degrees of Vessel 2 as measured from Vessel 1.

This second version is computed using vectors and needs as input the speeds and courses of the two vessels.

Note that these are 2D approximate solutions to a 3D problem. At long distances these solutions becomes inaccurate.The full general 3D solution should take into account the spherical nature of the earth.

View the source code to this page to see the underlying formulas used.

Created: 15 Aug 2000 Modified: 12 Aug 2011