Compass, Magnetic Direct Reading, US Navy Mark VIII (2) HH-3 Helicopter A flash tube

A flash tube

observers could determine the location of friendly aircraft using triangulation

made by Sperry part number 668899

Here is a Rapid Response

This plate is mounted with the slot or keyway parallel to the center line of the airplane

Compass, Magnetic Direct Reading, US Navy Mark VIII (2) HH-3 Helicopter A flash tubeHere is a fine example of the US Navy's Aircraft Direct Reading Magnetic Compass Mark VIII, as used in the SBD Dauntless Dive Bomber and the TBM Avenger Torpedo Bomber. This compass was installed above the pilots forehead, see image of the SBD's cockpit showing the location of this compass. This model was designated AN5732 1 later in WWII. The compass was illuminated electrically via bulb (included but operation unknown) mounted in a small compartment