Thanks for all the replies on this. However sadly on my next patrol U-48 hit a mine off the north east coast of England due to it's captain being enticed by a convoy sailing near the coast (I was assigned Grid AN52) . I knew there were mines in the area but thought I could get away with it, I was gutted  . Gustav Mindt and crew RIP. 
Nemo
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"I'm afraid there is no disguising the fact that King's obsession with the Pacific and the Battle of Washington cost us dear in the Battle of the Atlantic".
Sir John Slessor GCB, DSO, MC, DL
AOC-in-C Coastal Command RAF
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