I’m guessing the OP means if he hires an aircraft for 1 hr and flys outside the training area can he class this as a solo Navex. I would personally think that at the speeds most training aircraft go you would only make it about thirty miles away and can probably still see the area you came from. Not sure that you can really call
it a navex (no idea what the regs would say), but even if it is classed as one (as you have left the training area) your only wasting your own time in money as will get very little benefit from it.