1464

Item 1464

OTHER: Miscellaneous - Thoughtless Ideas - Adaptive Stagger Rotors (ASR)

Overview:

The two rotors move latterly to optimize the craft for different modes of flight.

During hover, the two latterly located rotors are set to a wide (side-by-side) configuration to give a reduced disk loading per square foot for better lift.

During cruise, the two latterly located rotors are set to the narrower interleaving, or perhaps intermeshing, configuration for better maneuverability.

Drawing:

The following information is specific to the UniCopter, however this concept is more appropriate for very large transportation rotorcraft.

Notes:
If the intent is to reduce the stagger all the way to an Intermeshing configuration then the below should be revised so that have the precone reduced to 4º and the rotors given a 4º outward tilt. This will give the inner retreating blades an angle of 7º above the horizontal and the outer advancing blade a -1º below the horizontal.

The two rotors are shown as moving laterally from R * 2 (114 *2 =) 228+" between hubs to 54" between hubs.

Precone 4º; 6º

Rotor radius 114" (9.5')

Sin of 4º (elevation / blade radius) = 0.0698; Sin of 6º (elevation / blade radius) = 0.1045;

Stagger = Radius * 1.1 = 125.4"

Gap, tip over rotorhubs centerline plane = 0.0698 * 114 = 7.95"; = 0.1045 * 114 = 11.94";

With precone of 6º and stagger of 27";

the centerline gap (tip over blade) will be 11.94 - 10.50 = 1.44" Not good at all.

the centerline gap (blade over hub ) will be = 2.82" Not good at all.

With precone of 6º and stagger of 54";

the centerline gap (tip over blade) will be 11.94 - 9.04 = 2.90"

the centerline gap (blade over hub ) will be = 5.66" Good

Drawing:

Rough preliminary drawing showing rotors in a wide intermeshing configuration.

Related Information;

Sikorsky has three or more patents related to changing the disk area loading by varying the diameter of the rotor. It is intended for tilt-rotor craft. One of the patents is 6,655,915 Drive system for the retraction/extension of variable diameter rotor systems
DESIGN: UniCopter ~ Rotor - Disk - Blade to Blade Clearance - 4-blade Rotors
DESIGN: UniCopter ~ Rotor - Disk - Blade to Blade Clearance - 4-blade Rotors
OTHER: Miscellaneous - Thoughtless Ideas - Stopped Rotor

Calculations:

US Patent Database Search:

Results of Search in US Patent Collection db for:
((((rotorcraft OR helicopter) AND configuration) AND rotor) AND ((side-by-side OR interleaving) OR intermeshing)): 76 patents.
None seem to be relevant.

Results of Search in US Patent Collection db for:
((((rotorcraft OR helicopter) AND configuration) AND rotor) AND stagger): 11 patents.
None seem to be relevant.

Results of Search in US Patent Collection db for:
((rotorcraft OR helicopter) AND stagger): 21 patents.
Non seem to be relevant.

Results of Search in US Patent Collection db for:
((rotorcraft OR helicopter) AND "intermeshing rotors"): 4 patents.
None seem to be relevant.

Results of Search in US Patent Collection db for:
(((rotorcraft OR helicopter) AND "advancing blade") AND rotors): 54 patents.
None seem to be relevant

Initially displayed: November 24, 2006 ~ Last Revised: January 3, 2007

The above utility invention 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.