UNITED STATES FLEET
HEADQUARTERS OF THE COMMANDER IN CHIEF
 
NAVY DEPARTMENT, WASHINGTON, D.C.
 
     
  FF1/A16-3(18)  
  Serial:  02834                                                                                               19 August 1943.  
     
  CONFIDENTIAL  
     
 
From: Commander in Chief, United States Fleet.
To    : Commander in Chief, U.S. Atlantic Fleet.
     
Subject: VB-132 Anti-Submarine Action by Aircraft REport No. 1, dated 19 July, 1943; Analysis of
     
Enclosure: (A) Subject analysis.
 
     
          1.        Enclosure (A) is forwarded herewith.  
     
     
                                                                                           
                                                                                                A. C. DAVIS.  
                                                                                          Assistant Chief of Staff.  
     
  Copy to:  
 
  CinCPac (2)
  ComAirLant (2)
  ComAirPac (2)
  ComGulfSeaFron (2)
  ComFairWing 12 (1)
  Comdr VB-132 (1)
  LantASWUnit (1)
  AirASDevLant (1)
 
     
   
  G. L. RUSSEL,  
  Flag Secretary.  
     
     

 

 
 

   
CONFIDENTIAL
 
 
ANALYSIS OF ANTI-SUBMARINE ACTION BY AIRCRAFT
 
     
  Unit:  VB-132                            Unit Report No. 1.                          Incident No. 3786  
     
  Base of Operations:  Boca Chica, Fla.  
     
  Squadron No. of Aircraft:  Not given.  
     
  Aircraft Type:  PV-1  
     
  Aircraft Commander:  Lt. J. C. Lawrence, USN  
     
  Location of Attack:  Latitude:  24-10 N  
                                 Longitude:  79-40 W  
     
  Date:  July 19, 1943.                        Time:  2327                      Zone:  Plus 4  
     
 
Weather: Night.  Full moon about 15° above the horizon.  Violent electrical activity and scattered rain squalls.  Seven-tenths overcast at 1800 feet.  Visibility ten miles up moon path, zero in other directions.  Wind 5 knots from 120.  Sea very calm.
 
     
  Depth of Water:  319 fathoms.  (In Santaren channel).  
     
  Mission:  Search.  
     
 
Approach and Contact: Breaking out of a mild thunderhead at 3000 feet altitude and heading in a generally down-mon direction, the tunnel gunner sighted a wake astern in the moon path.  The pilot changed course about 270° to the left, lost altitude to 2200 feet, picked up the left side of the wake and flew parallel thereto until sighting a northbound submarine up moon and three miles away.  The pilot immediately made a diving right turn to attack, keeping the submarine in the moon path.  No gun fire was exchanged, and the submarine was taken completely by surprise.
   
Attack: With the submarine fully surfaced, the pilot released six Mark 47 depth bombs with fuzes set to function at 25 ft. and spaced about 56 feet apart by intervalometer control.
 
     
 
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  Altitude of attack 150 ft., air speed 230 knots, target angle 280.
   
Reported Position of Explosions : Looking down the moon path, and using a 340-foot length of submarine as a yardstick, the tunnel-gun observer estimated that one bomb exploded about 70 feet short of the conning tower and that the second bomb exploded about 10 feet short of the conning tower, silhouetting the submarine.  Other explosions were not observed because of the abrupt pull out from the dive necessitated by low altitude and glassy water surface.
   
Reported Evidence of Damage: No evidence of damage was observed, and nothing further was seen after the attack.
   
Subsequent Actions of Aircraft: The plane remained in the vicinity of the attack for 45 minutes searching for the submarine or evidence of damage.  At the end of that time it was relieved in the area and, having reached its PLE, departed for the base.
   
Analysis of Attack: The approach to and conduct of this attack were nicely executed under conditions far from ideal.  Explosions occurring at the positions observed originally could be expected to produce some damage.  As is the case in many night attacks, damage could be obtained.
   
Comments: In the three minutes between the time the submarine was sighted and the time it was attacked the pilot made an accurate estimate of the situation and conducted the attack in a manner which leaves little room for improvement.  His first turn was made to take him down the wake, leaving maneuvering room, and placing him in a position to search up along the wake, using the moon path to disclose the identity of the object causing the disturbance.  Finding and identifying the submarine, he accepted the target angle then presented in order to make an up-moon run and eliminate the necessity for using flares.  Observing no one on deck or in the conning tower and having the advantage of surprise, he did not reveal his presence by strafing the submarine
 
 
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  before releasing his bombs.  When questioned about the use of flares after the attack, the pilot stated that the moon afforded ample illumination, and that at the time he considered that because of rain squalls and clouds the flares would reduce rather than increase the visibility.  The pilot's judgment in this point is considered correct.
   
  The following points brought out in the report are worth of mention:
   
          (a)  The tunnel station is the only one that offers a good chance of visually spotting an object in the moon path when the plane is flying down moon, and this squadron's doctrine required that the look-out be stationed there under such conditions.  While no look-out sector should be left uncovered at any time, the stern look-out is a particularly important post when flying in a down-moon direction at night.
   
          (b)  While the U.S. Fleet Doctrine for Anti-Submarine Warfare by Aircraft states that in a night attack the target should be illuminated by flares or searchlight, the pilot decided to depart from the provisions of the Doctrine because the target was already plainly visible, and he considered that the use of a flare would have blinded him because of propeller and windshield reflections.  The Doctrine is not meant to be inflexible, and if by departing therefrom the effectiveness of an attack can be increased, such departure is entirely justified.
   
          (c)  In order to ensure proper marking of attacks it is practice in this squadron to lightly tape a float light to the first and last bomb of each load carried.  Other
 
     
 
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  squadrons vary this procedure by suspending from the bomb release hook of each loaded bomb shackle or bomb rack a float light to which a small loop of light wire has been made fast.  Either method is quite satisfactory and is recommended for use by all squadrons.
   
  The report of this squadron was complete and well prepared.  The analysis and comments of the squadron commander served to round out the report and indicate that he is giving intelligent consideration to the problems involved in anti-submarine operations by aircraft.
 
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
                                                                                                                    Enclosure (A) to  
                                                                                                                    Cominch ser. __02834  
                                                                                                                    Dated 19 Aug. 1943.  
     
 
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