Rotor Tom,
Maintenance costs...........and an attempt to make it easier to fly with fewer parts. No one seems to ever question "is there a better way?" Perhaps there is not, but I'm crossing the "line in the dirt". If it works, all the better. If not, no issues from my point of view. I'm just willing to try. Look up on Youtube the "GEN H4" helicopter. The concept works, but the GEN H4 is fixed pitch with no "auto" capabilities. The whole gimbaled airframe is the only morphing part. The CG (in theory) flexes rather than a lateral shift as seen in Charles Seibel's helo. Most of my design is an attempt to improve and humbly "do it better than the GEN H4, Airscooter, and Seibels craft. Push the limits. My wife says I have OCD, but mechanical in nature. Rotorcraft are my favorite, but anything that questions the "usuall method" intrigues me.
You're right about the CG with most helos, but even from my limited experience, it appears as if conventional helo CGs are manipulated with the respective controls, but from one point atop the rotor mast within a static airframe. The ideal area for CG manipulation is lower down the rotor mast for better stability...like a pendulum...in theory..lol. The only way to do that is allow the airframe to change mechanically in flight and tie the weight of the pilot in with it as well. It's not as easy to see in small scale. Larger scale (full collective) there would be some what of a swashplate, but for collective pitch control only. I'm still in the crawl phase. I could be complety wrong, but what if I'm right? At any rate, I'm enjoying the process and I have no committments to anyone. Just my efforts. Thanks for asking. I do enjoy the feedback. We'll see what happens. First tethered flight is in a couple of weeks.
Look at the Baldwin aircraft Mono Tilt Rotor:
www.baldwintechnology.com/
Baldwin takes advantage of weight distribution at a distance farther from the hub and incorporates mechanical morphing.
The R22 uses a longer mast for better control and stability for a larger rotor disc area.
Dave