As one who loves to build flying models aircraft, I have always been intrigued by designs of Reimar and Walter Horten. The Horten brothers designed and built some of the most advanced flying wing aircraft of the 1940's., culminating in the Ho 229 the worlds first jet powered flying wing.
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Horten Ho 1V
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My own interest however is in the Horten Ho IV and I decided to build a flying scale model of this
type with the difference that it would have variable sweep.
The sweep I decided upon was from 14 to 25 degrees., the wing profile decided upon was
on the MH 45 developed by Martin Heppler. I had used this airfoil on several fixed wing models with good results. I included 2 degrees of washout at the wing tips as an extra degree of stability,
http://ift.tt/1hosDUH
At the extremity of the wing I included winglets which are connected to the center section
via a parallelogram so the winglets are always parallel to the center body regardless of the sweep.
The center section carry through spar was 15mm by 300mm long aluminum rod, the ends of which would slot into a sub spar supporting the wing. Steel pins would hold the whole in place and allow the wing to sweep smoothly fore and aft.
The center body contained the RC gear and batteries. Two 7Kg servos provided the fore and aft movement for the wings.
The wing was constructed around a “D” box,with carbon fiber, and spruce “I” spars, and covered with 0.5 mm balsa wood. After construction the whole was covered with stressed plastic film.
Test flying indicated that the rear 25 deg sweep center of gravity was so far from the 14 degree
sweep that it would be almost impossible to get enough mass forward to keep the same CG,
and to do this I would have to re design the whole center body. As yet I have not done this.
But it still looks great, and flies OK at 14 degrees sweep.
Here is a picture of my son Alex with “The wing”, at 25 degress sweep.
http://ift.tt/1OVXwKH
http://ift.tt/1hosFMn
Horten Ho 1V
http://ift.tt/1OVXwKB
My own interest however is in the Horten Ho IV and I decided to build a flying scale model of this
type with the difference that it would have variable sweep.
The sweep I decided upon was from 14 to 25 degrees., the wing profile decided upon was
on the MH 45 developed by Martin Heppler. I had used this airfoil on several fixed wing models with good results. I included 2 degrees of washout at the wing tips as an extra degree of stability,
http://ift.tt/1hosDUH
At the extremity of the wing I included winglets which are connected to the center section
via a parallelogram so the winglets are always parallel to the center body regardless of the sweep.
The center section carry through spar was 15mm by 300mm long aluminum rod, the ends of which would slot into a sub spar supporting the wing. Steel pins would hold the whole in place and allow the wing to sweep smoothly fore and aft.
The center body contained the RC gear and batteries. Two 7Kg servos provided the fore and aft movement for the wings.
The wing was constructed around a “D” box,with carbon fiber, and spruce “I” spars, and covered with 0.5 mm balsa wood. After construction the whole was covered with stressed plastic film.
Test flying indicated that the rear 25 deg sweep center of gravity was so far from the 14 degree
sweep that it would be almost impossible to get enough mass forward to keep the same CG,
and to do this I would have to re design the whole center body. As yet I have not done this.
But it still looks great, and flies OK at 14 degrees sweep.
Here is a picture of my son Alex with “The wing”, at 25 degress sweep.
http://ift.tt/1OVXwKH
via International Skeptics Forum http://ift.tt/1hosG2H
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