CONFIDENTIAL REPORT 2G-21
S16
     
 
FORMER GERMAN SUBMARINE TYPE XXI
 
 
 
 
ACCESS
  
 
 
 
SUMMARY
  
     
          Except for an increase in normal hatch cover thickness from 20 mm to 22 mm (.79" to .87"), hatch cover construction is identical with that on earlier vessels.  Actual measurements of hatch operating gear give dimensions on U-3008 which are identical with those on a type 9C-40 vessel U-889.  Dovetail gaskets also have been retained.  The brass hatch seats, however, have been eliminated.  
          Skirts are fitted to the maneuvering room, galley and lower conning tower hatches.  The control room remains the only compartment fitted with a lung charging manifold, and further, the oxygen system does not extend forward of the control room, so that it is not possible to bleed oxygen directly into the compartments forward of this point.  
          No change in practice is evident, and no further research is indicated.  
     
     
     
     
 
March, 1946
 
 
 
 
PORTSMOUTH NAVAL SHIPYARD, PORTSMOUTH, N. H.