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I would think it would be better to put the larger wings under the front or middle closer the the payload/center and have the smaller wings in the tail? Why would these designs do the opposite? enter image description here enter image description here

With the first (DAPRA's X-plane) you can see the weight is going to be put properly under the bigger wings but I also wonder: why have it fly with the smaller wings infront? If a teardrop shape is the most aerodynamic then the big wings should be in the front. Also it looks like a having the smaller wings in the back would increase stability in flight.

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    $\begingroup$ The second picture is of a concept plane that is severely flawed in its design. $\endgroup$ – ratchet freak Nov 6 '18 at 16:58
  • $\begingroup$ These are both concepts so its hard to say but they look like canard's like those found on the work of Burt Rutan $\endgroup$ – Dave Nov 6 '18 at 17:10
  • $\begingroup$ That's Daniel Wiegand's Lilium. I don't think the guy is dumb though. $\endgroup$ – Daniel Caoili Nov 6 '18 at 17:13
  • $\begingroup$ @DanielCaoili: See aviation.stackexchange.com/q/35436/520 for some discussion of the Lilium. $\endgroup$ – Fred Larson Nov 6 '18 at 17:53
  • $\begingroup$ I guess he is dumb lol $\endgroup$ – Daniel Caoili Nov 6 '18 at 17:58
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It's because with the canard configuration, the smaller stabilizing surface is a lifting surface instead of the down force surface of a conventional tail.

(A regular tail airplane is a seesaw with someone sitting on one end and another pushing down at the other; a canard airplane is more like a table with most of the weight at one end where the fat legs are and skinnier more lightly loaded legs holding the other end up. Canards get their pitch stability from having a steeper lift slope at the canard surface, whose airfoil is chosen to achieve that purpose, so the nose will rise with increasing speed and drop with decreasing speed).

So if you want to as much vertical thrust as possible from the available flying surfaces, it makes sense to use the Canard configuration where all the surfaces are lifting. Canards are nothing new; the Wright Flyer was the first. You don't see them everywhere because there are significant limitations, but in a VTOL configuration like this, the Canard layout is mostly a plus.

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    $\begingroup$ You don't see canards everywhere because they are actually less efficient, for aerodynamically stable configuration. $\endgroup$ – Jan Hudec Nov 6 '18 at 20:24
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    $\begingroup$ Yeah when the Varieze came out in the 70s it was kind of touted as a super-plane by homebuilt standards but they really aren't much faster than regular tailed airplanes with similar construction. Then there was the Starship fiasco, which confirmed for everybody that the concept was an aerodynamic dead end. $\endgroup$ – John K Nov 6 '18 at 20:34
  • $\begingroup$ If the canard configuration gives maximum lift (vertical thrust) why is it not more commonly used for high endurance aircraft, for instance: Solar Impulse $\endgroup$ – Daniel Caoili Nov 7 '18 at 1:53
  • $\begingroup$ It's not so much that but the fact that if you are going to use lifting thrusters that are integrated into the wings, you might as well have use a config that is all lifting wings. You couldn't put them on a downward lifting tail surface. In any case the theoretical efficiency benefit of the canard is lost in the noise of a bunch of other factors and there are lots of disadvantages, which is why nobody uses it today in mainstream a/c. $\endgroup$ – John K Nov 7 '18 at 4:06

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