Go Fly - Where to post

[jedi]

The UL strip is a strange place to post a Boeing Go Fly proposal (http://goflyprize.com/) but here it is as I see no other place for a true experimental aircraft design discussion.

Since the HBA sight is down as noted in the Hangar Talk section I am posting the following here. The proposal does qualify as an ultralight with the 254 pound empty weight UL limitation.

As Phase I of the Go Fly completion is nearing completion I would like to publish some ideas and observations for the entertainment of the many HBA critics. Go ahead and make your negative (or positive) comments. Check my math and fire your arrows. English to SI unit conversions are approximate.

Taking the 8 foot max dimension into account I have assumed a powered lift vehicle for the apparent VTOL or near VTOL requirement to operate within the 30 foot diameter 12 foot high cylinder. Furthermore a 200 pound minimum useful load is specified. Generally an aircraft that can lift its own empty weight is considered a good design so I made the assumption that a 250 pound empty weight and 500 pound gross weight would be a reasonable starting point. I am proposing to enclose the lift fans in an 8 foot diameter circular duct for safety and noise constraint reasons. Configuration study CAD drawings are available.

With these figures in mind I came up with the following specifications for standard day sea level operation.

Go Fly Entry Proposal J-1
Specifications:
Empty weight 250 pounds
Gross weight 500 pounds
Duct Outside diameter 8 feet (2.4 meters)
Duct area 50 sq. ft. (4.6 sq. meters )
Duct loading 10 pounds per square foot (50 kg/sq. m)
Duct inlet area 50 sq. ft. (4.7 sq. m)
Duct exhaust area 33 sq. ft. (3 Sq. m)
Hover downwash velocity 55 mph (25 m/sec.) -Assume uniform steady flow.
Hover power loading required 7 pounds / hp (1.8 kg/Watt) -Asssume100 % hp to thrust efficiency.
Hover power required 72 hp (54Kw) -Asssume100 % fan efficiency and zero duct loss.
Proposed rated power 100 hp (75 Kw) minimum for std. day S. L. operation.
Note: 150 to 200 hp (110 to 150 Kw) Max T.O. )(one minute) power desired for the proposed VTOL operation.

I am considering a 1/32 scale model to illustrate the proposed design. Some motor details and other design features are being evaluated. Additional information and suggestions are available. However, as others have concluded the likelyhood of success is problematical and therefore I do not anticipate an official design submission on my behalf. If any readers with a greater risk tolerance wish to advance the cause I welcome additional discussions.