In cruise flight,The power stops,add aft cyclic & lower collective as needed,
A +G is good for the rotor system, Aft cyclic loads the system ,It helps get air flow up though the disk, No flow no autorotation, a delay just drags your RPM down & it takes time to get it back. Pete is spot on.
ARMY/NASA tests are public record down loadable,
Heck you can trade speed for altitude and still do a good auto (& with a well timed flare on the bottom end no collective's needed.
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