It's Hobbico. Hobbico owns the Aircore trademark including most of the patents on making airframes out of coroplast. Want to slit a piece of coroplast, slide your landing gear wire through and make a fairing? Thats their patent. Want to slit a flute of coroplast and make a control surface? Their patent. Want to put all of your electronics, fuel/pwr and motor/engine on a "PowerPod" and swap that from plane to plane? THEIR PATENT!
Which was explained to us over on SPADworld years ago by the lawyers of Hobbico. We were not to make any money off the website. What we did do was show and discuss with a bunch of folks how to make airplanes that flew good, were durable and fun AND got a bunch of folks over the fear of flying hump. Flitetest is pretty dedicated to getting people into the hobby. They're quick build kits are spittin images of the old AirCore kits but they're profits go to keep the website going. If you look around at all the manufacturers that use coro for aircraft use, you'll see that Hobbico has been more then generous with the use of their ideas and patents.
As I've found more then once, great minds think alike. There was some dude down in Florida that would teach you how to make durable planes out of coroplast who didn't even know about SPADs or Aircore, just figured it out himself. You ever see that picture of Goddard looking at a V-2 engine? man was he suprised.
Flitetest may have come up with the swapable idea on their own, but it's been done and patented long before. You wanna give credit, you can buy some wheel collars, props and other stuff and send that check to Hobbico.