CONFIDENTIAL REPORT 2G-21
S74
     
 
FORMER GERMAN SUBMARINE TYPE XXI
 
 
 
 
ANTI-AIRCRAFT GUNS
 
     
 
SUMMARY
 
     
          The anti-aircraft armament of this type of vessel consists of two 30 mm machine guns in hydraulically controlled turrets at each end of the conning tower fairwater.  Pressure proof ready service lockers and dip pots are incorporated in the deck of the turret and swing with the guns.  
          Rotation of the turrets is hand controlled, and operates through a piston valve to determine the direction of rotation.  Considerable difficulty has been experienced with the hydraulic system because of sea water which has entered the system through the exposed operating gear and flexible hose fittings in the fairwater.  
     
     
     
     
     
     
 
July, 1946
 
 
 
 
PORTSMOUTH NAVAL SHIPYARD, PORTSMOUTH, N. H.