Hi FD,
Similarly I was doing some maths - and calculated that the difference in "g" between being parked on the ground on the Equator (but travelling at 40 thousand Km in 24 hours relative to space) and travelling at 1,000 Km per hour in the same rotational direction as Earth, produced an additional delta g of 0.0019. So Altitude + tangential velocity produces a total delta g of 0.0358.
Using S = UT + 1/2 Accel T squared)
Over 1 minute this would result in a vertical height change of:
0 + 0.5 * 0.0358 * 60 * 60 = 64 meters.
So there may be a very small delta g difference at high Altitude and speed, but 64 meters deviation over 1 minute of stick free flight is hardly significant.