To Lu
I must admit it sometimes goes over my head, but then again that is the challenge/charm of helo's it can keep you buzzy for a while.
I really want to try to make sense, but this is perhaps even more challenging then trying to understand it myself.
Fase lags :
gyroscopic precession=flywheel=simple zero excentricity rotor turning in outer space=90°='resonant system'
Real world=not always simple rotors=damping=not resonant
Real world=aerodynamic side effects=not inertial
So fase of a real world rotor is not always 90.
Examples:
For a typical stiff rotor (large excentricity or ridgid joints) the lag will be less
For the R44 (low excentricity non ridgid) with coning and wind it is more
Concerning the coning delta3
It is a dynamic system indeed Lu, but I showed a step responce that is extremely well behaved and fast (less than one rev) , so for all normal disturbances no negative side effects on dynamic behaviour.
I come up with another idea why this could be there : Robinson certainly knows how to reduce designs to the essence, which I would call good engineering practice (Lu you know a lot about maintainability, if I see what a steel plants some of the other rotor systems are...). May be it is by wanting a simple flapping delta3 system he introduced a coning delta3, just because of geometric simplicity, reducing the number of moving parts etc. But this coning delta3 just is an amplifier which can be simply taken care off be adapting the other mechanical (or hydraulic) amplifiers in the overall collective pitch link system. So it is a good approach to simplify mechanically the design.
Continuing to try to make sense....
Delta3
To Hilico
Yes I most likely can, but need to have precise enough data. I don\'t have a 206, but at the heliport I can get the data. Give me some time (2-3 weeks I have to dose the time for this hobby...) Any material is well come (mechanical design drawings of hub, measures, weights, profile, blade twist, this must be reasonably precise, otherwise GIGO)
As far as the assymetry of lift is concerned I worked out an explanation but allow me (sadistically I admit..) to let you guys come up with an explanation (or rebutal..).
Some extra material : the dynamic lift distribution in this case as looked from the front and the right rear (rotor without tip losses) looks like
I may try to find a way to have 3d quicktime pictures published on the net (this is what I get, and is very help full when looking into the proposed solutions)
Delta3
To Whirlycopter
you are right about the coning it is a function of trust. In autorot this is however not massively reduced, oyherwise we would fall out of the sky.
Delta3