Prandtl Wing, X-47B Rudderless Wing, Flying Wing, Non-Swept Wing Version (offshoot of Prandtl)

L Edge

Master member
When I investigated the X-47B, yaw was a problem. Turned to researching the Prandtl Wing to see how they resolved the issue. That would ruin the design(extending) but began to understand the issues to deal with the longitudinal and lateral stability of not having a rudder. So, came up with another way to induce yaw. Did not want a gyro to control it's flight.

Additional important point that all of the above have is problems dealing with angle of attack. That includes takeoff and landings. Watch the second chuck.
For additional info how TVN did it for yaw, go here:

Next came my swept wing design, it still required 2-3 degrees reflex, but I changed the flow pattern across the wing and reduced the funkyness of the longitudinal and lateral stability increased many fold. My personal goal to fly slow and fast in a very tight area in real good gusty conditions and takeoff downwind and land in a good gusty cross winds. The stabilizer solved most of the problems, but was crap in gusty crosswinds. (no crashes). So I added my new tool the "udder rudder" (in front of the prop) and can now say after 61 flights in gusty winds, it meet my goal. So I now have a stabilizer, end plates and a movable rudder,

In the video, gusty winds(look at trees) were coming from my back, wind would change in an instant, and pick up turbulance when I went above trees and flip it around. Even flew into wind nice and slow with nose up, and never faltered. With rudder in tow, able to fly crosswinds and stall turns which now is my "turn too" airplane that is easy to bring to field and stay alive in gusty winds. Again, the data from Prandtl wing provided clues to what to do especially with angle of attack.

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