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GESchwarz

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Oct 23, 2007
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Ventura County, California, USofA.
GESchwarz, It's similar to my own conceptual Tandem design, so naturally I like it, but I must ask why the twin vertical tails, is it just to eliminate the Vortex Tip Drag of the Horizontal Tail, some consideration of Spin Blanketing of the Vertical Tail, or other considerations like aesthetics?
George
The wings fold and the horizontal stabilizer is narrow, 8 feet, so that it is legal to tow on the roads. This makes the horizontal stabilizer span a little too small to be sufficiently effective. By putting the verticals at the tips, that increases the effectiveness of the span that it has.
 

pwood66889

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Feb 10, 2007
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1,952
Location
Sopchoppy, Florida, USA
One advantage of the "nose down" look is that the wing is below an angle of attack that generates lift. So once it is rolling on the ground, it tends not to lift off again. Don't shorten the nose gear, GE.
To my recollection, the Martin B-57 "Canbarra" had that cant which I admired. And the B-52 lifts off on initial climb out in that manner...
 

Aerowerx

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Dec 1, 2011
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Marion, Ohio
.... And the B-52 lifts off on initial climb out in that manner...
Because....

At the cruise altitudes the air is thinner, so to get the required lift they need a higher angle of attack on the wing. The wing is designed for the lift at cruise altitude. They also want the fuselage to be level during a bomb run, so it is angled with respect to the wing. So on the take off it is nose down.
 

GESchwarz

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Oct 23, 2007
Messages
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Location
Ventura County, California, USofA.
It's been a few years since I have done many updates on my machine. In that time I divorced a woman after 32 years of marriage and have now been with a far better match this last year and a half. I have retired from the military, space and commercial aviation manufacturing industry and have build my own home inspection business which has grown steadily the past 5 1/2 years.

On the plane, I have built both wings with integral fuel tanks. The biggest accomplishment is the insanely complex Grumman style wing fold feature. It was made more difficult by the requirement that the span when folded not exceed the Dept of Transportation vehicle max width of 8 feet. When structural members are fitted so close together, they must all be made to conform and contort to the requirements of neighboring members. Ouch!

So I am posting pics of how it looks now. All of the tail section members were completed years ago and have been stored in the rafters of the garage.
 

GESchwarz

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Oct 23, 2007
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Location
Ventura County, California, USofA.
Thank you, George.

My design is meant to be crashworthy and capable of handling off airport landings. Even though I live in Southern California, I have ambitions of traveling north to bush country and putting it down on some places up there; I think a robust tricycle can perform well.

It has nose wheel steering and so right now I am building the brackets and control linkage for the brake master cylinder, taking the form of a pull handle located immediately inboard of the fighter style throttle, on the left side of the cockpit. It will also have parking brake capability.

The torque tube with crank and control link you see near the trailing edge of the wing center section is to actuate the rather large slotted flaps.

I am entertaining the idea of using minor flap deployment as a means to accommodate the aft movement of CG with a passenger in the back seat. The flaps have a significant aft extension and will therefor cause the center of lift to move aft, extending the allowable CG range.
 

GESchwarz

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Oct 23, 2007
Messages
1,222
Location
Ventura County, California, USofA.
You know it, Vigilante. That’s especially true when the problem exists only in your head and there is no prior art out there. While I am following Grumman’s example, the application to my airframe and the space constraints greatly increase the difficulty. As a boy, I was fascinated by Grumman’s elegant solution. I purchased a rubber band powered balsa model of the Hellcat, and I modified it to make the wings fold just as you see in my photo to the left. It’s nearly 50 years later and I am doing it again, in full scale. In some ways boys never grow up. :)
 

GESchwarz

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Oct 23, 2007
Messages
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Location
Ventura County, California, USofA.
Thanks Dennis. It is a prototype, so everything is hand done. Now and then I have to scrap a part, if I make a mistake and it cannot be reworked to the correct configuration. More often, a part can and does get modified to work, scars and all, bearing its troubled past. There just isn’t time to make a new part so that it will look perfect. I will be lucky as hell to actually finish this thing and fly it before I die. Given all that life throws at me, this plane has always taken last place to things like mowing the lawn and spending time with my sweetheart.
 
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