Although they've been around for ages, for some reason paper airplanes have never been adopted for commercial use. It could be because they get soggy when wet, they lack any kind of flight controls, or because you would need an incredibly huge piece of paper in order to make one big enough to carry a human passenger. In any case, practical paper airplanes have now perhaps come a baby step closer to reality, with Tailor Toys' Power Up electric power module for paper airplanes - it allows you to mount an electric propeller on your paper airplanes, so they can fly under their own power.
The kit consists of a capacitor that clips onto the plane's nose, which is connected to a rear-mounted propeller via a carbon fiber shaft. The capacitor takes a 20 second-long charge from a separate battery pack, which contains three AA batteries. One charge provides enough power for 90 seconds of flight. That's probably plenty of time, considering that users presumably have to chase after their powered paper planes in order to get them back.
That being said, a neat add-on for future versions of this product might be remote-control ailerons, so the plane's flight could actually be controlled. Of course, once it got that complex, it would probably be simpler just to buy a complete RC model plane.
Although you can add the module to whatever design of paper aircraft you like, the Tailor Toys website does feature instructions on making planes that should work particularly well with the kit. The Power Up module is currently available on Amazon, starting at US$17.49.
The video below shows what kind of flight is possible with the device.
Source: ThinkGeek
Actually, I don\'t know why people still insist the shape of the wing is the only thing that allows planes to fly. That\'s just not true, because otherwise, paper airplanes (now they can be powered) or even the rubber band airplanes can fly perfectly well without any wing curvature.
http://www.thenakedscientists.com/HTML/podcasts/scrapbook/show/2011.07.12/
Thanks for pointing me to the Naked Science article, I\'ve been looking for something on the topic.
I\'d like to hear an experts explanation but a quick review of the Coanda Effect and the Bernoulli Effect seem to indicate that Coanda Effect creates lift from the flaps when they are an extreme angle and Bernoulli Effect creates life from the fixed part of the wing.
That would also explain why The Naked Scientists link shows the wing at an extreme angle to the thrust vector.
A plane flying upside down does not disprove the Bernoulli Effect or support the Coanda Effect. There are many more principles in play in flight then these two and, besides, not all planes can fly upside down. Those that can usually sacrifice the ability to sustain forward flight, or sacrifice speed, etc.
For example, specialized stunt planes can fly straight up and then hover by using thrust in a vertical position instead of lift.