Resultant vector i.e. effective speed, and observed angle i.e. wind drift, displaying device for e.g. recreational application, has elongated scales provided with longitudinal slots and mark cutters, where one scale is graduated of mark

摘要

The device has a set of transparent or non transparent elongated scales (1, 2) provided with longitudinal slots (4) and mark cutters (5), where one of the scales is graduated of a flat and circular arc angle mark (8). Another scale slides on the former scale along one of the longitudinal slots by a staff connecting the two scales. The latter scale presents a circular bore (6) in one end of the mark cutters, where the bore is remote from the longitudinal slots.