Original U.S. WWII Sperry S-1 Bombsight in Steel Transit Case - Unissued British Holsters as the simplified design makes

as the simplified design makes it more resilient

BUT we do not know for which it was designed

The cylinder is also only 35mm long

For the United States

Original U.S. WWII Sperry S-1 Bombsight in Steel Transit Case - Unissued British Holsters as the simplified design makesOriginal Item: Only One Available. Manufactured by the International Business Machines (IBM) the Sperry S 1 bombsight was designed by Elmer Sperry, Carl Norden's former employer. It had several distinctions from the Norden, and some advantages. The Sperry gyroscopes spun at 24,000 rpm, compared to the Norden gyros which ran at approximately 8,000 rpm. This higher rate of rotation overcame the tendency to precess, so there was no leveling mechanism