"Andrew Crane" wrote in message
...

wrote in message
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To avoid this problem, BJ tilted the entire rotor head rather than
changing the pitch cyclicly. In fact, the pitch on the blades only
changes when the collective is moved and not the cyclic. This results
in the grease being retained for a longer period of time. It still
needs frequent regreasing, but at least you don't need a new set of
bearings after each hour of flight.

OK - silly question. On the face of it, it seems to make a lot of sense to
do it this way

- simple connection - you could probably lose the swashplate somehow
too
- fewer cyclical forces on components
- less chance of mast bumping

What are the downsides other than potentially odd handling?

I should imagine that the control forces would be enormous and pushing the
rotor head forwards would cause the fuselage to pitch backwards for a
start-off.


Not if you do it right.

Dennis,

I had no idea BJ did that. If you remember, I wanted to "rid" my coaxial
of the swashplate. Reading the above post, I got excited about the loss of
the swashplate but how did BJ keep collective control without one. Or did I
misunderstand?

Phil


Andrew,

I'll guarentee that if you tilt the mast "my way", the tail doesn't pitch
down. I'm tilting a mast at a very low CG....PLUS.... I'm moving it forward
to slightly change to a forward CG. Same for left, right and to the rear.
Sounds weird but works. It add control complexity, but at least it's not up
in the head spinning.

Phil

Back to lurk mode.