You can load anything into a fighter bay if the bay's big enough.
You can load anything into a
hangar bay if the bay's big enough. You can build underground PDCs to house the Thunderbirds team, the submersible aircraft carrier from "Battleship!" the movie, or even the Space Battleship Yamato. You can build 100,000 ton capacity hangar bays on 300,000 ton displacement generation ships to reload the box launchers on two of your 40,000 ton supercruisers simultaneously, with room for destroyer flotilla to spare.
Which is important, becasue it's the only way to reload box launchers away from maintenance facilities, and is why the NATO supercarriers in Steve's campaign have enough hangar space to squeeze in a destroyer when all of their birds are launched.