Keith:
As the collective is lowered the aircraft starts to descend and the induced velocity and the induced power both fall to zero. As the aircraft accelerates downwards the direction of the total reaction is tilted in the direction of rotation at some points along the blades and is tilted in the opposite direction at other points. It is only when a certain rate of descent has been achieved that the sum total of the different parts of the total reaction is sufficient to keep the blades rotating in the correct direction and to produce sufficient lift to support the weight of the aircraft. When the sum of lift plus vertical component of drag equals the weight of the aircarft the ROD becomes constant. The actual rate of descent depends upon a number of things include blade pitch angle and aircraft weight.
Yeah, but irrelevent.
I have known several hundred helicopter pilots over the years, but none of them have flown theoretical discs. They have all flown real helicopters with real rotor mechanisms.
..and they all imagine their thrust in terms of a man rowing a boat down a canal a la your little analogy?
You are using the behaviour of real systems to support arguments about theoretical physics, then you are saying that the actual mechanical arrangement of the systems is superfluous. That line of argument is clearly nonsensical because the behaviour of the real systems is determined as much by their physical characteristics as it is by the theoretical physics
I referred to actuator disc theory because it is the right one to tackle this meme of thrust without THP, and I prefer it to your rowing boat story.
When an aeroplane is standing still on the ground with wheel brakes applied the THP is equal to Thrust x propwash velocity.
I don't recall ever saying that. Feel free to paste a quote though, if you can find one.