Small men were generally chosen as ball turret gunners. There was no room for a chute in this cramped position. He usually did not climb in until after takeoff and climbed out again before landing. Unlike the B-17, the ball turret was hoisted into the fuselage for takeoff and landing.
    Charles Laynor remembers the ball turret gunner got frostbite of the ears on one mission, and that his eyelids were frozen shut during the Linz mission (#5). It was not unusual for the temperature to drop to -50 degrees when the ball turret was lowered into the slipstream after the aircraft had achieved altitude following takeoff.

 

A page from the January 24th, 1944 issue of Life magazine. The article dealt with the new compensating sights being used in heavy bomber gunnery. Click on image to enlarge.