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Old 3rd Sep 2020, 04:45
  #193 (permalink)  
The Sultan
 
Join Date: Dec 2000
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Ifmu Wrote:

I have no knowledge of Raider or Defiant, but they got it working for X2. I personally don't see any reason why it wouldn't work for the new aircraft. They have excellent dynamics people, not just in theory but supporting the aircraft in the field and in the air.
The X-2 was a tiny concept demonstrator with an occupied area of around 5 feet on the center line. It is simplistic to get that small of an area smooth in only one direction and at one frequency such as N/rev. The problem becomes significantly harder trying to suppress vibration over a large three dimensional space, which the last S-97 pilot report I saw says they have failed at. In fact the pilot quotes indicated the vibration (and loads?) were so bad that the crew were reluctant (note I didn’t say scared) to go above 180 knots once it became obvious the latest cure for vibration being tested did not meet expectations. As the 97 still appears to be restricted to 180 knots for even high profile demos they apparently failed to overcome the issue.

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