Thank you very much for answer. I agree that the easiest way is to
  design two different reduction gearboxes - also it will be more
  reliable and (hope) lighter. Every gram is counting.


  Our goal: two person in tandem VTOL aircraft, max tow 1200kg/2670lb,
  power rotary 2x300hp, rotor diameter 2x4.5m/15f, wing area
  4m2/44.4sqf, wing sailplane laminar airfoil 20%-18%, wing span
  6m/18f, airplane minimum drag coefficient Cx0 0.018, composite type
  structure. Machine can be fast if the problem with rotor flutter is
  solved. We would like to use turbo compressor charged Renesis
  rotary. Grateful for suggestion and opinion.

  Sincerely,
  Viktor

  My kids and families were home for the weekend.  They rented
a DVD, which I saw part of before dozing off.
I think I saw your aircraft thoroughly field-tested
on the video Avitar  :)

R


Now R be nice.

Paul Lamar


Paul,

Thank you very much for a nice joke. I couldn't take a breath for some time.

In the film AVATAR (where everything is possible :-) was
presented fictional "flying device" quite similar to French
Nord Aviation-500 from late sixties. For difference Nord-500 was real and flying.

www.aviastar.org/helicopters_eng/nord-500.php

We are thinking about a small version of Bell/Augusta
609 with rotary engines. We cannot decide which landing
gear to choose for the project: tandem (like some sailplanes,
sea harrier etc.) or standard "tricycle". As usual weight
is most critical.

Sincerely,

Viktor

I am a fan of VTOL pardon the pun.
http://www.rotaryeng.net/VTOL.html
However ducted fans don't work in the 150 MPH to 400 MPH
speed range. If you have enough HP to go 500 MPH
then consider them. We are talking thousands of HP.
That means turbine engines. Note the successful V22
Osprey does not use ducted fans.

BTW see if you can get the extra blank lines out of your
messages.

Paul Lamar

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