Hmmm its totally possible - check the market's storage section, check if it has a patrol base/specific building (if desired), create the fleet on a semi-recurring basis, if the ship is destroyed in the fleet, remove it from the inventory. For bonus points, make a new submarket instead of just using storage so that the player can store ships that they want to use later and that they want to go on patrol and die.
Just... those ships will get blown up at some point by the RNG of the autoresolve, most likely while the player isn't even in the system. I wouldn't trust any ship I actually want to use later to that kind of thing.