Simplicity is the ultimate sophistication Leonardo da Vinci
Seems like every other day I read about some "perfect" paper airplane design on social media, and I hope to see my XO or something like it, only to find some fancy taped-up masterpiece. Don't get me wrong, I've taped, glued and stapled airplanes together every way possible and still do.
That being said, there is no debate, the XO o-wing is the perfect paper airplane design. I could literally fold 60 planes per hour with no tape or scissors, and they would all fly great. The XO is simple and sophisticated.
In any case, the first time I saw an o-wing (annular) paper airplane I was stunned by the shape and flying characteristics. I've never been able to learn the history of the first o-wing design and would guess China, but I've heard rumors it was born at NASA. Since there seems to be no agreed upon name for the o-wing, I call mine the XO because of the construction, appearance and I love this design!
ATTENTION - Major fun factor modification discovered. Attach a short piece of fishing line to the top of the o-wing with a staple and see what happens when you sling it. Cool part is that my first field test was at the Aerospace Museum of California.