At the center there is also a thermal generator 100 meters below you. You have to figure out the wind direction and search downwind for the thermal. If you fly out of the play area, you will reappear on the other side. So will the thermal. You can change the parameters of the game from the options menu.
All parameters are in metric units.
They are not saved when you leave the game. The program will need the egavga.bgi file to run. If a floating point coprocessor is present, it will be used. On a 386DX40 without the 387 it will run OK, but not if it runs just 20MHz. Hang Gliding Demo program.