The NASA "Muppets" use the simple definition....Of course I'm in awe of all the complicated equations
GS is a function of TAS, Wind vector, and nav fix displacement...easy...that's why we can't stop the leak
So much crap
did you know that dG = [dU+pdV+VdP] - [SdT+TdS]
it's true; but as written it's a little pedantic, as I have included all possible contributions
..of course it can be expanded a little too
Lester