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Old 19th Apr 2019, 04:26
  #45 (permalink)  
Join Date: Mar 2005
Location: Poplar Grove, IL, USA
Age: 53
Posts: 837
Originally Posted by Jack Carson View Post
I had an opportunity to fly the X-59...
When I was recruited to design and build the X2 FBW I spent a lot of time studying the ABC and talking to the old timers. Everything you say about the ABC is true. The X2 and its successors are different in two respects. The blade planform is a leap way beyond what you had on the ABC. The drag is way lower even without the nifty inter-rotor fairing. Also due to the driveline, speed of the main rotor is controllable. It doesn't autorotate away like the ABC, even at flat pitch. The ABC was a cool aircraft, and it advanced the state of the art of blade construction, but still seemed to be designed around hover. You probably remember the twist of the blades. What is good for low speed is bad for high speed, and visa versa. Time will tell for the Defiant, numbers don't lie.
Bryan Cotton
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