It is theoretically possible to roll one if you were really determined, roadster. As beagle rightly says normal flight envelope will prevent this...unless you are silly enough to switch off some flight computers. Not permitted of course, or a career enhancing strategy.
One ex-military braveheart did perform such a manoeuvre in a turboprop belonging to my previous employer...and had to find alternative employment as a result. Which prompts me to question the thread title "ex-military"? These were all civil aircraft flown by civil pilots, whatever they USED to do for a living. When does one stop being ex-military? If I save the day with some superb flying next week is that how I'll be described? What if I close the airport by dragging a wheel bogie into the grass?