When fly mode is off you will be locked at a constant height.
You can look up or down and move forward but you will only move forward.
When fly mode is on and you look up and move forward you will move up and forward at the same time.
i.e. your height will change as well.
Barry.
One of the forum moderators.
Versions 6.5 to 27
i7-10700 @ 2.9Ghz, 32GB ram, GeForce RTX 2060 (6GB), Windows 10
Lenovo Thinkpad - i7-1270P 2.20 GHz, 32GB RAM, Nvidia T550, Windows 11