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Old 29th January 2007 | 01:25
  #62 (permalink)  
IFMU
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Joined: Mar 2005
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From: Poplar Grove, IL, USA
Originally Posted by Dave_Jackson
The spread between the Coaxial-ABC and the Interleaving-ABC will be even greater.
Dave
Dave,
What is the drag penalty for those two masts sticking up, with not only double the profile drag, but also interference between them? That's one thing that seems unequal.
As far as the 15% benefit with respect to disk area, how much of that is undone by the fact that the lift vectors of the synchrocopter waste some of their effort against each other, since they are inclined outwards? You could probably do a ROM estimate of the lost lift of each rotor by multiplying it by the cosine of the shaft angle.
I have read that the original ABC had big vibration problems. It had two 3-bladed rotors. How is anything with 2-blade rotors going to be better? I would bet you would have a hard time getting to respectable single rotor helicopter speeds before you lost your fillings, or busted something.
-- IFMU
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