-30-
 
                                                 49
 
Copy No. 171
                                           86
 
     
 
Permanent Order No. 61
 
     
          After heavy depth charges and aerial bombs in the vicinity of the boat, after which obstruction of the torpedo tubes through bending or twisting must be reckoned with, the following overhauling of the tubes is to be carried out as an immediate measure as far as is practicable:  
     
  1)  Attempt to draw out the torpedoes.  If the torpedo will not come out, or only does so with difficulty, block the tube for surface and under-water firing.  
     
  2)  In drawing out torpedoes, watch out for any visible signs denoting difficulty pf passage.  
     
  3)  When the torpedo is out, dismantle the pistol and crew in the breech cover in the warhead.  
     
  4)  Inspect the inside of the tube carefully, paying special attention to the fore part of the tube and to the bowcap.  
     
  5)  Put the piston-plunger into the tube, and slide it into the tube with the torpedo.  If, by this method the piston-plunger slides right to the forepart, the tube is clear for both kinds of discharging.  If the piston-plunger sticks, unload the torpedo and draw out the piston-plunger by means of tackle or a pulley block.  Block the tube for underwater firing.  If, in spite of this, the torpedo can be loaded and unloaded without special difficulties of passage, and the tube shows no visible signs of damage it can be made free for surface firing without scruples, because for this the piston plunger remains in a resting position.  
     
                                                                                     F. O. U-boats Operations  
                                                                                            00417/FS