Yep, the speed is determined by the attribute "vertical_speed" under "navigation" in the unit blueprints. The Astraeus is currently set to 100.
Do you know the command for sending units between layers? Could this be used feasibly for a unit going from WL_Land to WL_Undersea or whatever they renamed it recently.
You can use the special move command that the orbital transport has, or you can set a hover time. None of this can do what you are asking for.
if i am reading correcting you change the speed for that unit, and if it did work does it change the speed for the AI as well if you are playing the GW part or the mutilplayer part of the game with the AI.
No he's changing the speed of the decent from the orbital layer to the air layer. Though changing a unit's speed is even simpler.