0629

Item 0629

OTHER: Helicopter - Inside - Single Rotor - Rotor X Wing - Concerns

Concern:

The retreating blade cannot produce sufficient lift during transformation.

To see the calculations that support this statement see; OTHER: Helicopter - Inside - Single Rotor - Rotor X Wing - Improving Lift During Transformation:

I believe that this very same problem existed with the Sikorsky S-72 X-Wing, the Boeing_X-50 and Sikorsky's proposed Reverse Velocity Rotorcraft.

Possible solutions are listed here; Improving Lift During Transformation.

This problem can be overcome with twin main rotors that are located on a common lateral axis. A possible, but complex, idea is; OTHER: Miscellaneous - Thoughtless Ideas - Stopped Rotor

Possible Concerns:

How much power is lateral component of rotor velocity going to consume pushing the vertical portion of the blade in front and rear retreating quadrants?

The blade should have a symmetrical airfoil profiles, such as NACA 0012. This is because the upper surface on the advancing side will be the lower surface over a portion of the retreating side. However, the advantage of using an asymmetrical profiles on the advancing side and the entry and exit portion on the retreating side may do more for lift than the inverted asymmetrical airfoil, in the slower velocity, on a portion of the retreating side.

The circumference of the reverse velocity region will be where the forward velocity of the craft is neutralized by the X-axis vector of the blade's speed. However, the Y-axis of the blade's speed is not neutralized and it may create an oscillation about the Z-axis. The location might be adjusted slightly to neutralize some of the lateral force for a slight penalty on the longitudinal force.

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Last Revision: March 19, 2007

The above application of active traversing blade twist in a helicopter is openly and publicly disclosed on the Internet to negate an entity from patenting it, to the exclusion of all others whom may wish to use it. ~ Reference patent law 35 U.S.C. 102 A person shall be entitled to a patent unless - (a) the invention was known ... by others in this country, ..., before the invention thereof by the applicant for patent.