U-480 - 1st War Patrol Page 8

 

 
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    continued      
    13.06.44 Norwegian Sea    
        Malfunction of the 3.7 cm cannon.  
        Check firing had been conducted with the weapon about 30 minutes before the attack by the aircraft.  The gun did not fire properly, which is why the mechanic is working on it.  
      [correct terminology for gun parts?] When "Aircraft" [readiness condition] was set again, the weapon did not fire.  On my order:  "Semi-automatic" the cover was removed and an attempt was first made to bring the swing wedge into the loading position with the slider crank, as this did not succeed, the attempt was repeated with the wedge opener key.  Unsuccessful, the entire base piece firmly wedged and pinned down.  
        During later investigation and attempt to unscrew the bottom piece. Slider crank broke off the shaft of the clamping segment.   
        Only after hours of work and breaking down all the small parts could the bottom piece be removed.  
        Cause of the malfunction was:  
        The cam of the thrust cam shaft had obviously broken off in a material defect and was located inside the gun between the teeth of the cocking segment. As a result, forward and back movement and the swing wedge were not possible.  
        The weapon was operable again for semi-automatic shooting.  
        Behavior of the crew.  
        When the crew came in contact with the enemy for the first time, the crew did very well.  Failures and malfunctions were quickly eliminated. The active defense of the flying boat by the twin 2 cm was particularly excellent, and ammunition replenishment was carried out while shooting.  
    08.00 AF 4991 At periscope depth.  
      W 3, Sea 3, cloudy, Vis. medium    
    12.00 AF 4967 At periscope depth.  
      W 3, Sea 3, cloudy, Vis. medium Day's run:   
                                     Surfaced:       57.2 nm  
                                     Submerged:    30.5 nm  
                                                           87.7 nm  
    16.00 AD 4964 At periscope depth.  
      W 3, Sea 3, clousy, Vis. medium    
    16.18 AF 4964 Surfaced.  
    16.29   Wanze detection on 150 cm.  
           
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