The default hydrophones (GHG) can be used whilst on the surface, but the upgraded version (KDB) can't. Except, I think it can in the stock game, and had to be modded so it wouldn't work on the surface... sorry if I am confusing you
John, I had a similar situation the other day, except my last couple of torpedoes didn't sink the ships they hit. But I surfaced and sank 7 of 9 ships with my deck gun.
Today I found a 14-ship convoy containing 5 troop transports and 9 other merchants. My entire torpedo load of 14 brought down 3 ships, but my deck gun claimed another 6! So I got 110,000 tons, just like that
Who even needs torpedoes? Get in there with the deck gun, man!
Silly damage models
