When ever i try to fire the torpedos bertaa battle ship's torpedos make the game crash but i don't know which weapon mod i need.
It is possible either the mod downloaded wrongly or you've overwritten one torpedo with another. Try downloading the thing again, reinstalling it or get a console readout.
Check that any required soundfiles and scripts are in the right folders as this tends to be the source of this type of problem.
Checked the Bertaa mod's comments and no-one's mentioned this before, which could be indicative of a specific problem.
The only requirements for the mod are QBAutostart and the launching framework, but only if you want to launch shuttles, and choosing the right hardpoint for with or without nanofx2.