Sunday, December 19, 2010

Symmedian Point

Shift a celestial navigation LOP triangular plot center slightly toward the short side (sides) for an improved probable position (symmedian point)

Thursday, December 2, 2010

Horizontal Sextant Angle Plot Made Easy

Make short work of plotting horizontal sextant angles by determining the arc radius using a chart plotting board, radar plotting sheet, or the simple formula (0.5 mark A to mark B)/ sin(horizontal sextant angle) = radius. Once the radius is known then a chart plot is performed by arcing the radius off navigation marks A & B then plot the arc of position from the radius point intersection to determine an estimated position. The chart plotting board image above shows a radius solution for a horizontal sextant angle of 45° and a distance between marks A and B of 16.6 nautical miles.