I was passing north of the Orkneys when I found and attacked a lone C3. I fired two G7a's at her, but both passed underneath the hull and continued on until they ran out of fuel. Both were set to run at 10m, two less than the C3's draft of 12m. What happened here? Does SH3 model torps running too deep? My only other guess is bad weather and high waves - winds were something like 15m/s at the time.
The setup was otherwise pretty close to perfect - both torpedos would have hit amidships at 90 degrees. Grr!

Fortunately I ended up chasing the C3 down again and sinking it with two G7a's, set to 5m.