SR-71

L Edge

Master member
Going to re-do my SR-71 with moving up to cw/ccw 70 mm EDF's. Lost paper design over years, and of course took out 64's to do other planes and that ended its' life. That means my Viggen is now going to be destroyed to get at other EDF. Have you seen the HH SR-71 that's coming out soon? A beauty, so I decided to see if I can increase my speed and yet takeoff/land in a short distance without a gyro for stability.

As usual, to get going, I have no FFF foam left so it is going to be made out of thick depron(white) base and add some black Adam's foam board for fuse shape. Will look ugly, will design for stability first. Then it can be modified and painted black with red trim. So aside with Photon and onto this.

Next is the paper design to work off.

Goals:
1) Make it lightweight.
2) Be able to launch by hand or a short takeoff and design for a slow approach/short landing strip.
3) No gyro needed and have a stable flying environment.(no wobbles)
4) provide yaw(differential thrust) for crosswind landings as well as a trim for yaw when going vertical.
5) reduce the pilots skill level from a 4/5 to a 3/5 range.
 
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L Edge

Master member
sr-71+.jpg


Since no brown foam available, had to jiggle numbers around to fit 2 thick depron sheets. The seam is where the 2 triangles meet the fuse. With the battery(3300mah) up in the nose with the nose gear, the foam seams, the main landing gear, I am going to epoxy a 3" balsa strip starting over the imbedded hot glue carbon rod that will be end over the outer main landing gear. That way, hard impacts on landing (F=ma) will reduce damage.
I am going to fiddle around to get some shape of upper fuse and the balsa could be re-shaped to fit inside the upper fuse. So for now , I will put it on the bottom.

To keep the wing flat, a carbon rod will go across from one end to the other (thru the engine ducting) to reduce bending and most important to strength the outer wing from bending and fluttering. By the way, air flow disturbance is at a minimum at the exhaust.

Back to the paper to outline the rest.
 
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