I don't know if this has been asked yet, but...
Were torpedoes able to be reloaded while on the surface or did they normally dive to reload?
I've never read anything definitive but I've gotten the impression that they could be in calmer seas.
I would think in seas that were even a little rough, it would be near impossible and extremely dangerous.
In game, I've always tried to limt my reloading to calmer seas(under 10 m/sec wind) and not while going balls to the walls around convoys and such. I try to wait until I'm submerged or I'm away from the action and I can slow down to do it.
Thanks.