Airspeed Indicator, Sensitive, 700MPH, Army Type F-1A, US Army Air Corps, WWII F-89 made by Sperry

made by Sperry

The knob adjusts the indexing 'aircraft' within the dial to align the perspective of the pilot to the horizon indicator

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

000 CDIA aircraft clocks where produced and equipped with Waltham’s famous 37 size

model 828 type 19Y1S

Airspeed Indicator, Sensitive, 700MPH, Army Type F-1A, US Army Air Corps, WWII F-89 made by SperryThe 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