~S~ Chaps,
Dam good information all of it ! (nice table SkyPup)
Bucky M8, yup thats what "Dirty" is alright , "Clean" being gear up/flaps up.
The "clean" stall speed gets faster the higher you go until it matches the maximum possible forward speed of the aircraft.
This is by definition the planes "ceiling"
This maximum forward/level speed,(usually quoted @ sea level), gets slower as you go over a certain altitude.
This is because the engine likes "thick" air LOL
Thus , on a graph drawn with clean stall speed , max forward speed, and altitude, you end up with a flight "Envelope"