Note VMCG is not weight specific. For a 747-400, standard day, VMCG for full thrust is 126 knots, while TO2 (15% reduction) VMCG is 117 knots.
True and not so true. The FAA defines Vmcg as the most aft CofG and lightest weight, worst case, but doesn’t apply crosswind. Actual Vmcg will be much higher when crosswind is applied. In the 747, it’s about 1.3 knots increase per knot of crosswind. It’s about 1 for 1 in the C-5. If you ever saw the two parked nose-to-nose, you’d see why the difference. I can’t say for the 747 but the Vmcg chart in the C-5 1-1 has about a 20 knot increase for a wet runway.
GF