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Old 30th Apr 2009, 16:28
  #427 (permalink)  
Dave_Jackson
 
Join Date: Apr 2003
Location: Vancouver, BC, Canada
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It is with some trepidation that I comment on perceived improvements to rotorcraft, since Senior Pilot has made it apparent that it is not a subject for this forum.


Mart (Graviman)

Going off-topic related to the X2, but staying on-topic related to the ABC.


Does the circle density in your plots relate to induced velocity?
Yes. The above drawing shows the the rotor disks as having the same diameter. In reality, the disks of the Interleaving would be smaller for a comparable craft with the same gross weight. In the drawing, the density of the circular lines represents the induced velocity during hover.


I'm a bit bothered that your calc does not account for interaction between one rotor and another. There should be some azimuthal variation with each rotor. ........ The retreating side needs to be off loaded regardless of config.


The above drawing shows the craft with its rotors. There should not be any significant interaction between the two rotors.


Regarding aerodynamic interaction between the rotors and the fuselage;
During cruise, the retreating sides of the rotors are over the fuselage. The retreating blades will be producing minimal thrust due to the ABC.
During hover, the downwash on the fuselage would be reduced due to the inclusion of Active Blade Twist.
In both the above cases, the passage of 8 blades over the fuselage will increase the frequency of any downwash, and this is a benefit.


Dave
Just trying to find and disseminate improvements in VTOL craft.
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