I notice that the Program Manager Steve Glusman worked on Comanche. This head looks roughly how i envisioned that head to look, from various descriptions. From the TV program "Ultimate Helicopter" i remember freeze framing the image, but never seeing a pitch link system. At the root is a "damper system", which looks to me as if it also acts as an electric pitch actuator. That ring at the base is either an azimuth sensor, power slip ring (either DC brushed AC brushless) or both.
I gather it can also absorbs blade flexural modes, so maybe blade torsional wavespeed has been tuned to to equal blade centrifugal tension wavespeed at midrange rpm. This means that through active pitch control the blade dynamics can be damped down at the aerodynamic source - this requires intense real-time computational modelling of blade dynamics. Alternately there may just be a damping system built into the blade root.
Since Comanche achieved either 12% or 15% effective offset hinge (i forget which), then Nr change induced coning could be accomodated by blade flexure alone. The Nr range would allow efficient silent hover, while beeping up for forward flight or manouvre.
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Ian, somehow i missed that OPOC thread. Don't quite see/remember how crank mech works, but it is this designs best feature. The debate about 2-stroke vs 4-stroke is an old one, and for my money 4-stroke wins. The power advantage for a given displacement is at best x1.5, which becomes less as turbo charging does more of the compression (since turbine captures more energy in 4-stroke). Also at high RPM 2-stroke scavenging struggles, so the power advantage is further reduced.
This design will suffer from the 2-stroke need to lubricate the piston rings, so that you cannot help but let oil into combustion chamber or exhaust. The emission standard is not quoted, so i can only assume they are relying on helicopters having loose standards. This is the main reason 2-stroke are being dropped for land/sea machines (although there are some interesting designs carried over for historical reasons). Partially burnt oil is absolutely fowl, believe me.
Mart