by H » Sat Dec 10, 2005 2:25 am
A quick way of keeping the old mission is to open it with notepad or wordpad, immediately click on "save as" from the file menu, type in a a new name and save (also change the name within the text and save before closing). You can then use this newly named mission for your edit.
As Cody_Coyote states, you can easily enough change your runways but, if the waypoints are too far away, you'll either have to cut your throttle and then warp or you'll run out of fuel. Reducing the throttle and flying the distance (perhaps with a time increase) may work but is still distance dependant (if flying WW2 planes it could, in reality, cause havoc with the engine; it was done, however).