Hmm puzzling. Were these merchants armed? I noticed three of the sinkings are within 1 or two minutes, yet there is some distance between where they sank. Could some of the merchants have been taking friendly fire from the convoy?
One of the ships sunk is in black instead of red. I haven't played with contacts on in awhile. I know red is for enemy, blue friendly and green is neutral. Not sure what black signifies.
Was it storming. Its possible you damaged the ship but the game attributed the sinking to storm conditions instead. Just making stabs in the dark until someone more knowledgeable comes along.
