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Old 23rd May 2010, 12:08
  #657 (permalink)  
Graviman
 
Join Date: Nov 2004
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Cattletruck, don't forget that autorotation just means that the main rotor does not require positive torque to rotate. So a clutch is not a requirement for an autogyro flight mode. I would not be surprised if during the proposed 265kias dash speed the main rotor actually supplied torque to the pusher prop.

Sultan, nobody says that 168kts is fast. But, it does prove that the technical issues have been overcome and that the ship is back on the path of a 250kts cruise. Imagine how routinely cruisiing 68+kts faster than your Cobra would feel.

Once X2 has proven itself, i would not be surprised if a 3rd generation ABC (counting S69 as 1st) began to consider what would be required to develope a rotor system which could approach turboprop speeds. Early days...

Chris, that the aerodynamics near the root are more complicated than the CFD predictions does not surprise me. I was actually impressed that the flow was sufficiently non turbulent to allow a vane type of device. Can you give any specifics of the difficulties encountered?
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