H5606

Thought I'd ask here for a good blade angle for initiating and continuing an autorotation strictly for straight down, descent of a four blade rotor system of approx. 250 sq. in. and body-weight of a pound and a half.

I'm looking for the slowest or longest descent rate.

Thanks for any help here -

H5606

Disregard thread title question -

What is a commonly used fixed angle found in the majority of simple autogyros?

TIA