Beat me to it on Equivalence. The fascinating thing is that the
instant his fingers stop resisting gravity, he is weightless (no real airflow yet.) No transitional time.
I'm perplexed by the thread drift since it sometimes seemed to veer, erm, bunt off into talking of negative g rather than attaining 0 g. Thread drift is usually beneficial, nit-picking, quite different.
I'm sure the pilot was able to fly level inverted without much thought and then the issue becomes - what would be shown on a g-meter?
Neil Williams. For those not around back then, the man knows a little about inverted flight. Having suffered what might be called, asymmetric dihedral, i.e. a broken wing, he flew back to base inverted, flipping the right way up for the landing. Nifty.
Zlin wing Structural Failure Report - Neil Williams