Yeah but Navy fatigue is different, no? Carrier landings have a heckuva lot more shock & salt air creates more corrosion problems. I would think land-based F-18's would have much longer lifespans. Plus I think we'd be talking about F18-E/F models which are essentially a different aircraft from the F/A-18 A thru C.
It depends. Yes, the load conditions are different for the landing gear and arresting hook for land vs. carrier landings. But pulling 9g in a dogfight is no different for carrier or land-based jets, those cycles add up no matter where you’re landing.