I have always been led to believe that fear of heights (vertigo?) is only noticeable when you are connected to the ground via a structure etc. Only once have I felt vertigo when flying & that was when I looked down the launch cable whilst being winch launched in a "Primary" glider; releasing the cable & all became fine again.
Went up the CN Tower many years ago, my 4' tall cousin stared at my terrified look as I backed up against the wall as the lift shot through the building's roof where you get in the lift & muttered aloud "scarred of heights are we?" soooo embarrassed!