Hmm, strange. Had the same thing happening when i was on my way back from us waters in sep. 1942. Came across the exact same ships. 2 large tankers, 2 medium cargos and 1 trampsteamer, and no escort around.
I dived, picked the two large tankers and sank them from about 3000m. While the two went down i got closer and noticed that none of the ships was armed, so i surfaced to train my deck gun crew a little bit. Watching the shells hitting the waterline with my binoculars i saw that they were all irish!
36000 tons of neutral shipping. I consider sailing to argentinia as i surely will face a firing squad when coming home...
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