Training Booklets, Set of 3: Upper, Lower Ball, and Tail Turrets A4 Skyhawk A volume of air enters

A volume of air enters the mouth of the tube

The Mark 18 sight was used in some turrets of US Navy aircraft as well as in the cockpit of the Korean War-era F-86 Sabrejet fighter

The assembly itself is ~3

It is in exceptional condition given its age

Training Booklets, Set of 3: Upper, Lower Ball, and Tail Turrets A4 Skyhawk A volume of air entersThis listing is for a set of 3 original WWII era armorer training booklets for gun turrets used in the heavy bombers B 17 and B 24 compiled by the Air Forces Technical School, 2nd Echelon Power Operated gun Turret Division, Lowery Field Colorado, February 1943. Includes: 1) Sperry Upper Turret, 13 pages 2) Sperry Lower Ball Turret, 11 pages 3) Consolidated Tail Turret, 14 pages Each booklet reviews turret installation, service, maintenance,