Airspeed Indicator, Sensitive, 700 Knots, Army Type F-1A, US Army Air Force, WWII
The Army Type F-1A Airspeed Indicator was used across a number of US Army Air Corps and Air Force aircraft during WWII, including heavy bombers B-17, B-24, B-29, medium bombers B-25 and B-26, as well as light bomber A-20, according to the Accessories Interchangeability Chart dated Feb 1945. It was also used in versions of US Army Air Force WWII fighters P-38, P-39, P-40, P-47, and P-51. This F-1A was made by Kollsman, part number 739BU-03, and has a serial number prefix of AF44, indicative of a 1944 manufacturing date.
According to the spec sheet in the Index of Army Aeronautical equipment Volume 6 Instruments, dated 1944, the Army type F-1 is a sensitive airspeed indicator. The pointer makes one revolution every hundred knots. A smaller inner dial indicates tens of knots.
It is in exceptional condition given its age. The dial and glass are intact. This indicator appears to have been refurbished as the dial is non-luminous and the pitot and static ports are capped for protection. It is not accurate as evidenced by its 50 knot reading while at rest. See photos.