RC Warship Combat. Sprang up in the mid-late 80's.
Want to remember that frames can be sturdy, but hull planking can only be balsa. There are rules on how much foam you can add for recovery, too. The premise here is that the models are unarmored in effect, so that combat is possible (or a person could just use a FG hull and not be shunk).
The ships have some middling dedicated plan sets, since simplicity is the order of the day, that and adapting gun mounts to the "guns" available. Different classes of ships were/are allowed different mixes of fixed and trainable weapons (IIRC). That, and the ships are meant to be sunk, and then recovered.
It's a fascinating niche in ship modleing, especially in RC ship modeling.