Compass, Aperiodic, US Military Aircraft, Pioneer 1811-1-B Smiths The D-1 Pitot Tube had

The D-1 Pitot Tube had two designs

And here we are

P-40 Warhawk

and Dec 1949

1 Dual Manifold Pressure Indicator

Compass, Aperiodic, US Military Aircraft, Pioneer 1811-1-B Smiths The D-1 Pitot Tube hadThis appears to be a post WWII Direct Reading Aperiodic Compass used at the navigators station in US military aircraft. Made by Bendix, part number 1811 1 B. It appears to have never been put into service judging from its superb condition. An aperiodic compass, after being deflected, returns by one direct movement to its proper reading, without oscillation. It may have also been used in maritime vessels. It is similar to a WWII era D 12 compass, which