brian, an Auto-Prop fits you definition #3
the autoprop turns it's blades, to be parallel to the axis of the
shaft, resulting in less drag than in the fwd or reverse direction,.
How is that not feathering?
I an unfamiliar with the autoprop.If it turns its blades' angle of
attack to the near zero angle (actually slightly negative angle) that
minimizes drag, then this is said to be a feathering prop.
[one realises that a blade's angle varies with distance from the hub,
so that the idea of a fixed angle of attack is a slight abstraction]
If a prop system allows the blades to fold at the hub in order to
minimize drag this is usually described as a folding prop.
If a prop system allows the prop blades' angle of attack to vary so as
to maximize power transfer at the present water speed, this is said to
be a variable pitch prop system.
Let me ask Jim specifically (in order to avoid interjections from the
lunatic fringe) which of these three types of prop system he would
call the Autoprop?
Regards
Brian Whatcott Altus OK
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