Depending how much movement you want the jet to do on the deck, you may be able to trigger a waypoint for the AI pilot and then use SETVELOCITY to get the unit into the air off the deck.
I suspect you'd have to use a series SETVELOCITY to do it, a couple to send it down the deck at increasing speed, then a couple more with some UP vectors once it reachs the end of the deck. Once airspeed is up the AI will fly from there.
Complicated I know, but I suspect thats about the limit of it.
Not sure if the Catapult Deckplate can be triggered to rise from "outside" the Nimitz scripting sorry, instead you could maybe smoke the deck to simulate the steam catapult.