On Monday, October 7, 2019 at 5:07:25 AM UTC+13, Dan Marotta wrote:
I can roll up into a 90 degree bank and, if I don't apply up or down
elevator, the plane won't turn.Â* The nose will simply knife downward..Â*
So, am I clinging to something?Â* Think vectors and the vertical and
horizontal components of lift.

If you are flying straight and level and then roll into a 90 degree bank while keeping the same elevator position then you will enjoy turning with 1G of centripetal acceleration. Until the nose falls through. And then you'll enjoy a 1G pullout (more as the speed builds).

The only way you can *not* turn in that 90 degree bank is if you actually moved the stick forward to the position that would give you a zero-G pushover in level flight.