Originally Posted by
scifi
Quote.... 'you will descend'
That ain't necessarily so...
Yes. If you've got a massive thrust-to-weight ratio then it's quite manageable. We used to do it with radio controlled planes all the time; most of the electric ones can easily fly with a 90 degree bank angle.
For "normal" aircraft, I suspect that you might be able to keep the nose above the horizon (as specified in the original question) with the elevator - but that's not going to translate into a climb. It'll be essentially a conventional stall, as the airflow over the lifting surface (side of the fuselage in this case) is insufficient to support the weight of the aircraft.