sorry for being vague, but since there's no real equivalent for ship-based helicopters in WC, i assumed that small capships must carry some kind of armed strike craft - fighters fit the bill
i guess putting fighters on destroyers doesn't make a lot of sense, but Vigilant is designed to sweep many systems quickly & operate independently, so it needs some fighters (drones can't do everything)
anyway, it's for a sequel idea to WC: DDX, where another Vigilant-class ship, this time modified as a fast stealth carrier, is built