Black Swan ships

[Convoy Assassin]

I have been trying,without success,to locate the 5 Black Swan ships,I am beginning to think that they have vanished in the Bermuda triangle.

Has anybody actually located these ships? if you have will you please tell me how to find them & where you found them.

I have tried search patterns(Lawn mowing) box searches and frequent submerging with engines stopped & listening for them,still nothing.

Thanks in advance.