Compass, Direct Reading Magnetic, Type B-16, 1818-4-A Grumman The compass is ~5 inches

The compass is ~5 inches diameter and 3 inches deep

This 92-page book was published in 1979 as an overview of the P-51 Mustang Fighter

The indicator also provides visual indicator of oxygen flow similar to the WWII-era "blinker" device: as the pilot inhales/exhales

marked for the Air Corps US Army

The C-7 displayed engine RPMs in hundreds

Compass, Direct Reading Magnetic, Type B-16, 1818-4-A Grumman The compass is ~5 inchesHere is a Direct Reading Magnetic Compass Type B 16, which was used across nearly all bomber, fighter, transport, and trainer aircraft of the US Army and US Navy. This compass was typically installed at the top of the windscreen or on the instrument panel, such as seen in B 17's, P 38's, and P 51's, and many others. This example has a serial number prefix of AF 43, evidence of the 1943 year of manufacture. The compass still contains its damping fluid