Vmca, Vmcg from an Operational Viewpoint
Vmcg is less than or equal to Vmca. I looked through my reference library but could not find any definitive information on it. I do remember from way back in a FlightSafety HS-125 training session this topic surfaced and the answer was that it had to do with the nose wheel. On the ground you have nose wheel steering, ground contact and the rudder. Once you are in the air you only have the rudder.