Jeppesen PN-1 Plotter
When the centre hole is placed over a meridian line and the top edge of the scale is aligned with the proposed track the heading to steer (zero wind) can be read from the fixed protractor. Distance is read from the 1:500,000 or 1:1,000,000 scales. Manufactured in strong laminated vinyl and supplied in a clear plastic slip case. 33.5 x 10 cm.