Gyrosyn Compass C-2A Sperry Master Indicator 653894-6B C-119 Boxcar USAF P-2 Neptune 25 inches diameter and 4

25 inches diameter and 4

There is no noticeable swing or waver

as appeared on the flight engineers panel of aircraft of the US Navy such as the patrol bomber / seaplane PBM-5 Mariner (see illustration showing the location on the panel from the PBM-5 flight manual dated 1944)

which existed with that name from 1918-1926 until it was renamed Air Corps US Army

The CW-22AAD meter was used with Gun Directors Marks 33

Gyrosyn Compass C-2A Sperry Master Indicator 653894-6B C-119 Boxcar USAF P-2 Neptune 25 inches diameter and 4This is a Gyrosyn Compass Master Indicator Type C 2A made by Sperry part number 653894 6B. The Master Indicator was part of a 5 module system combining the functions of a directional indicator and a magnetic compass, introduced in the late 1940's. See the diagram of the system with an explation of its function in the photo gallery, including a diagram of this specific indicator. An illustration of its position on an instrument panel is in the photos