FPS tanks at higher altitudes

[AirBadger]

On the ground I can get 40 - 50 FPS with the 737 in the VC. But when I get up to higher altitudes (e.g., above 20,000 ft.) my FPS tanks to about 22 FPS. Anyone else seeing this? It seems to be isolated to IXEG's 737.

[Litjan]

I would put my money on VRAM exhaustion in combination with Orthophotos.

Cheers, Jan