I found a rocket service that gives you a boost to an altitude that you request. I went up to 3000 meters.
It warns you to wear a parachute but I didn’t.
I notice that at that altitude you fall with terminal velocity of about 10 m/sec if you are ‘flying’ and nearly 100 m/sec when you are not.
At lower altitudes you fall more slowly if flying.
In ‘mouselook’ mode you can fly up or down in addition.
If you fly down you fall much faster.
You may fly up but still you can not maintain altitude, but you fall slower.
You can spiral around looking for things up there.
With practice you can manoeuvre to land on them.
It is like sky diving but the day I tried it was so smoggy that you couldn’t see far.
You could not see the ground until you got near.
It was like a very smoggy day in Los Angeles in the 50’s.