Protractor, Aircraft Navigation Plotter, US Naval Observatory PZL The indicator has two pointers

The indicator has two pointers

This is an authentic WW2-vintage Landing Gear Pressure Indicator

The glass is loose and appears to need a new gasket

Brake Mean Effective Pressure (BMEP)

Protractor, Aircraft Navigation Plotter, US Naval Observatory PZL The indicator has two pointersThis is a WWII era Aircraft Navigational Protractor (aka Aircraft Plotter) Kit as used in navigator crewed aircraft of the US Army and Navy. This particular protractor has a tag from the US Naval Observatory stamped 1945. It would be fitted to the navigators map table to plot and revised the aircraft's course. The kit appears to be complete. Included with the protractor machine itself are two steel rulers in cardboard sheaths which attach to the