Airspeed Indicator, Sensitive, 700MPH, Army Type F-1A, US Army Air Corps, WWII F-89 The manual appears to be

The manual appears to be complete with hundreds of pages of text

Mach speed is indicated from 0

It is in fine but 'experienced' condition for its age

model 828 type 19Y1S

made by Sperry

Airspeed Indicator, Sensitive, 700MPH, Army Type F-1A, US Army Air Corps, WWII F-89 The manual appears to beThe 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 739U 03, and has a