Paul Kemp 
Friend or Foe [EPUB ebook] 
Friendly Fire at Sea, 1939-1945

During the Second World War, there were over 100 instances of naval engagements between ships, submarines and aircraft of the same side. In the past there has often been a reluctance by the authorities to admit to these losses but with operational records now available, it is possible for historians to explain how a good number of ships and submarines were attacked, damaged or sunk by the forces of their own side.