Yes.I admire the builders ingenuity and building skills, but other than being a conversation piece, I'm not sure what it accomplishes. Does it actually do anything "better" than conventional tractor or even pusher designs ?
Probably does - but if it does not, he can bust through 1/8" plexiglass with his head.I would also have a lot of concerns about having to enter/exit the airplane from underneath. In the event of a landing gear collapse or other landing mishap, is the canopy quickly removable ?
People do, within their abilities, what they want to do. I'm guessing that he designed, built, and flew it because he wanted to, and that is what makes it, for him, better than a conventional design.I don't mean to sound critical of the builders design, because he obviously put great effort into both designing and building the airplane and deserves credit and respect for doing so. There is always something to be said for doing something just to prove you "can".
Those papers were written by Zimmerman himself!Here you go, Autodidact, the two classic Zimmerman papers:
NACA-TR-431 Characteristics of Clark Y airfoils of small aspect ratios (1933)
NACA-TN-539 Aerodynamic characteristics of several airfoils of low aspect ratio (1935)
And continuing my quick and dirty math from above, a 16' diameter circular wing would have a whopping 201 sq ft of area. With some care that might be able to fold up the wings carrier-style (two 6' outer panels on a 4' fuselage/center section) and still fit in a 20' shipping container.
You really want to hold a stick connected to a control surface in a highly pulsating airflow like that? "It's the new ACME Hand Massager! Wait, there's more!"... The model airplane guys get away with cutting a hole in the wing for the prop, I'm not sure how it'd work at this scale?
Don't misunderstand me. Each of these things accomplished a designers purpose just like the UFO does for its designer. None failed to accomplish it's designed purpose, but to what end? If the designer only wants to build something for his own amusement and it performs as designed, then I congratulate him. If his purpose is just to prove it "Can" be done, then I again applaud his success. Myself, I'm more of a function over form kinda guy. The airplane appears to fly well in level flight and gentle turns. The shape or form of the wings appears to make downward sight lines difficult especially when landing. As I mentioned earlier, entering and exiting the airplane from below is somewhat difficult and dangerous if landing problems occur. To me the functionality of a clear line of sight and quick emergency egress would be far more important than the novelty of an uncommon form or shape. Remember, this is not just a difference in our appreciation of what the builder accomplished, but the fact that someone's life is at stake because of a design concession.I had a friend who died from burns suffered in a crash because he couldn't be extricated quickly enough. I would like it a lot better if the canopy opened instead of the fuselage bottom. Again, I respect what he accomplished, but it wouldn't be something I would ever consider building or flying.OK, they are truly useless objects.
The UFO however does work like it should- it flys and flys well.
The same thing that would happen if you made 15 meter glider type wings & bolted them on. You'd have very different flight characteristics and probably need bigger tail feathers. ( I always advocate bigger tail feathers )