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Old 14th Jul 2009, 20:46
  #474 (permalink)  
JohnDixson
 
Join Date: Mar 2007
Location: Hobe Sound, Florida
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FBW for Rigid Coaxials

Graviman, you are on target w/re to your comments to Shawn. And the areas where FBW are of advantage only begin with the subjects that you noted. All of the controls in the XH-59 were mechanical, thus there was this very sturdy looking crank in front of the copilots shins that was a swashplate phase angle adjuster! Actually, it is a tribute to a very smart team that they accomplished what they did.

And then there is the very basic subject of control sensitivity vs needed control range. That always present compromise was as you might imagine exacerbated by the very high control power/sensitivity of the rigid rotored ABC. In fact, a control system change in the direction of lower sensitivity ( thus lower range ) was at the heart of the accident in the first prototype and one could easily argue that with a FBW control system, the "problem" would have been a non-issue.

So as the X2 proceeds, they have the tools within the FBW system to develop the solutions to the complex tasks and implement them behind the scenes, so to speak, such that after development is complete, a relatively simple, straightforward flying task should present itself to the operational pilots.

Thanks,
John Dixson
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