I'm running a 1941 campaign wherein both sides are deploying large numbers of subs on converging courses: one side sing them to screen for opposing surface ships, the other trying to get past the screening subs to the surface units behind them. I'm doing night-spotting for surfaced subs for both sides during their surfaced time at night; but, could subs detect each other underwater at this time, historically? The odds seem infentisimal, but I know there WERE sub-vs-sub combats in WW2.
Any thoughts or suggestions are welcome - thank you.
