Original U.S. WWII Sperry Aircraft Gunsight K-13 Compensating Sight 81mm Mortar The ramrod is unfortunately absent

The ramrod is unfortunately absent

Darling stated that the re-inforced collar on the 2nd ramrod guide is an invention of John Pratt

is revealed

showing normal “In and Out” marking from the runners but overall in a nearly Mint state

Original U.S. WWII Sperry Aircraft Gunsight K-13 Compensating Sight 81mm Mortar The ramrod is unfortunately absentOriginal Item: Only One Available. The K 13 Compensating Gunsight, made by Sperry, is an electrically powered gunsight designed to compensate for altitude and airspeed. Typically mounted on the rear housing of a . 50 caliber machine gun from a side waist gunner position in the aircraft. Used in Boeing B 17 Flying Fortress and Consolidated B 24 Liberator bombers during WW2. It was a late war innovation that used the aircraft altitude and speed with the