Radar plotting sheet

A radar plotting sheet, also called a maneuvering board, is the printed polar diagram, range rings on a 360-degree bearing scale, used to plot relative-motion radar observations by hand and solve for a target’s true course, speed, CPA, and TCPA. The standard solution is the OAW triangle: O is the target’s first plot, A its later plot giving the relative-motion line, and the own-ship run is laid off to W, so the WA leg yields the target’s true course and speed. At least three timed plots establish the trend. The sheet underpins manual radar plotting where ARPA is absent or as a cross-check.