All restrictions are lifted, including “too fast”. You can do acrobatics (not possible with a DC-8, of course), land on the next runway, and “do whatever you want”. In fact, if you remove all restrictions, you can’t finish the game. Therefore, only the decision to clear the game when the aircraft lands and reaches a flight speed of 0 kM/hr is left in place. I decided to remove the restriction because I thought that if it is a flight simulator, the game should not be set to terminate during flight. Incidentally, this restriction was lifted about 27 years ago (around 1995). In order to maintain the gameplay, I have also uploaded movies with only the “altitude/flight area/landing location” restrictions. If you are interested, please take a look.