Abstract: A navigation plotter for use with a map or chart having depicted thereon a line depicting a desired course and a compass rose. The plotter comprises a protractor designating angular graduations about a center axis. A linear scale member is mounted upon the protractor for rotation about the central axis. A grid on the linear scale member includes a plurality of sets of parallel lines. The respective sets of lines intersect one another repetitively and serve as visual guides to assist in aligning the linear scale member by arranging one set of lines parallel to the desired course while the protractor is held in registration with the compass rose. A series of radial lines on the linear scale member project from the central axis and are respectively parallel to the individual sets of lines in the grid. The radial lines register visually with the protractor to indicate the compass bearing corresponding to the selected course on the map.

Abstract: A navigation aid for visually indicating to an aircraft pilot or other user the distance and bearing to a destination by use of radio navigation information from two pre-located sources. The axis of a compass rose representative of the destination is preset spacially and angularly with respect to the two radio stations, each represented by an individual compass rose longitudinally movable along primary elongate arms connecting the three compass roses. Three secondary elongate arms are pivotally movable about the respective compass rose axes. By setting two of the secondary elongate arms to represent the bearing of the aircraft to each of the radio stations, distance to the destination can be read directly from the intersection of the three secondary elongate arms. The desired bearing is indicated by the angular relationship between the compass rose centered about the axis representative of the destination and the secondary elongate arm pivoted about its axis.