xxxx           (  D  )  
     
 
Federal Building
 
 
90 Church Street
 
 
New York, N.Y.
 
  373.  
     
  SUBJECT  :  Analysis of Aircraft Attack.  
     
  TO             :  Commanding General, Air Forces EDC & First Air Force, Mitchell  
                        Field, New York.  
     
          1.        At 1643 May 14, 1942, Capt. Fitzgerald's patrol in B-25A from 393rd Bomron sighted, at position 3935N 7214W, a submarine 2 miles distant, fully surfaced and proceeding on a 50 degree course at 8 to 10 knots.  The sub was light blue or gray in color, over 100 feet long, but due to angle of approach other distinguishing features could not be defined.  An attack was made at 25' altitude 200 miles per hour before sub had time to become completely submerged; the end of stern was still visible at time of bomb release.  Three Mark 17 DS's were dropped with 25' setting, two of which were released from a run at 90° from course of sub, the last being released at 20°.  First bomb contacted surface of water on swell ahead of conning tower.  Second bomb was 25' over.  Third bomb was same as first.  A large brown thick oil slick about 75' in diameter suddenly appeared on the surface.  An object resembling a piece of blue cloth appeared on the surface.  30 minutes after attack a string of bubbles 2 miles long appeared at surface and was still visible after 2 hours.  
     
          2.        Analysis:  
                          a.  Assuming that 2st bomb contacted water 10' ahead of front of conning tower and that its under-water trajectory would be at right angles to course of sub, and that dropped from 25' altitude at 200 miles per hour its horizontal displacement underwater would be at least 50' prior to detonation; the first bomb must have detonated at least 50' from longitudinal axis of sub.  
                           b.  The second bomb being over at water contact would be even more distant at detonation.  
                           c.  With the third bomb, however, dropped at 20° angle instead of 90°, the DC probably detonated within lethal range, assuming it to have been dropped 20° astern or rather that 20° head on to submarine course.  
     
                  3.  Evaluation:  
                         Based on evidence of oil & debris and bubble train and the physical probabilities, this is considered to have been a successful attack.  
     
     
     
     
     
     

 

     
  L11-1  
      Serial 00162  
     
 
HEADQUARTERS
  
 
COMMANDER EASTERN SEA FRONTIER
 
 
90 Church Street
 
 
New York, N.Y.
 
     
  SECRET                                                                                        September 18, 1942  
     
     
  FROM:              Commander Eastern Sea Frontier.  
  To:                     Commanding Officer 393rd Bombardment Squadron.  
  Via:                    Commanding General, First Bomber Command.  
     
  Subject:              Assessment of Damage to Enemy Submarines, Report of  
                            By Cominch's Assessment Committee.  
     
  Reference:          (a)  Cominch's secret serial 00929 of September 7, 1942.    
     
          1.        Included in reference (a) is an attacked by Bombron 393 on May 14, 1942, at Lat. 39 - 35N; Long. 72 - 14W.  It is gratifying to note that the assessment made was "probable damaged".  
     
          2.        Transmission of this document via registered mail within the continental limits of the United States is authorized.  
     
     
     
                                                                                              T.R. KURTZ  
                                                                                              C of S.