Ball turret

The ball turret is a spherical, altazimuth-mounted gun turret fitted to American bombers during the Second World War, most widely the Boeing B-17 Flying Fortress and the Consolidated B-24 Liberator, and also used by British and Chinese air forces. Designed by the Sperry Corporation, it housed a single gunner along with two heavy machine guns and their ammunition in an extremely cramped sphere, forcing the gunner into a fetal position with his hips at the bottom and his legs braced on footrests, and there was typically no room inside for a parachute. As a manned defensive gun position rather than a remotely operated one, the ball turret was one of the key defenses a bomber had against fighter attack from below.