Stu,

No doubt, you have more important things to do then that of discussing the
pros and cons of twin main rotors, but I sincerely believe that the
intermeshing configuration may be the salvation of recreational rotorcraft.
The following four points support this belief.

1/ Duplicity of parts: The cost advantage has to do with production.
For example, it may take 20 minutes to process the work order, set up the
drill-press and the jig etc., to drill one hole in an angle. The drilling
of the hole may take only 0.5 minutes. Therefore the time to drill one part
will be 20.5 minutes, whereas, the time to drill 2 parts will be 21 minutes,
which is 10.5 minutes per part.

2/ The pictures on the following web page show the compactness of an
intermeshing assembly. This assembly includes the rotor-hubs, the
flight-controls and the drive-train.
http://www.germanvtol.com/fl282rotor...l282rotor.html

3/ Here is a proposal for a recreational helicopter, which could offer;
reliability and partial homebuilt construction at a price far below
$100,000.00. http://www.synchrolite.com/Dragonfly.html

4/ Here is a possible organizational structure for the proposed
helicopter. http://www.unicopter.com/Dragonfly_Organization.html

Dave J.