There was a BBs challenge once as to how high you could get in a Me163. Offline I was able to reach somewhere over 95K when my entire plane dissapeared from my view.
The trick in the 163 at that alt is that it's both stalling from lack of airflow and shuddering from high speed so you have to walk a tightrope to keep it climbing.
Also, at 90K the AH terrain dissapeared meaning instruments only then, as I said, at about 95K the entire cockpit dissapeared.
I was, however, able to keep control, descend and land which was also part of the challenge.
