Antiaircraft gun carriage. Inspection of a thirty-seven millimeter antiaircraft gun carriage parts. With 300-plus-mile-per-hour planes for targets, antiaircraft assembly must be a precision instrument to permit the gunner to keep on his target. Inspection is as rigid as in instrument manufacture. War program production scene in one of Pennsylvania's heavy industry plants now converted to the production of vitally needed military equipment. AETNA. Ellwood City, Pennsylvania