The Cyclogyro

One of my favorite timewasters is to dig through archives of old vehicles and scrapyards while looking for unique machines that never made it to production. My favorite concept car would be the Cadillac Cien. Built for Caddy's centennial in 2002, it featured a 7.5L V12 Northstar, which cranked out 750 HP and 450 lb.-ft of torque. Its style was in-tune with the F-22 Raptor fighter plane, and it included night vision, thermal imaging, and a HUD. It was also in one of the coolest action chases ever.

As far as seafaring craft, consider the Ikkar. This 2010 concept cruise liner relies on wind and solar power for both power and propulsion. It also transforms, in every sense of the Optimus Prime-meaning of the word. The single hull can expand into a trimaran, and it provides each guest suite with an ocean balcony and access to a boardwalk. It remains a concept though, just like the Cien.

That's not to say these vehicles will never be built however. Even 80 years later, prototypes can be revised and innovated to the point where they're finally useful, or at least practical. Such is the case with the cyclogyro. It was dreamt of in the origins of vertical takeoff vehicles, but was radical even for those primitive designs. As such, it never flew until 2011.

Canadian-born and American-educated engineer Jonathan Edward Caldwell taught himself aerodynamics in the 1920s, when heavier-than-air flight had finally reached a point of consistency and understanding. Airships and prop planes were the only modes of aviation available, but engineers knew that stabilizing propellers with a vertical axis also created lift, and the autogyro was a testament to that understanding. Caldwell envisioned a flying machine that generated vertical lift through the use of the Magnus effect. It's the same principle that helps golf balls and baseballs maintain flight.

Caldwell patented the cyclogyro in 1928. Two paddle wheels -- akin to steamboat paddles -- were equipped with four airfoils, and they replaced the main wings of an airplane. In some designs, paddle wheels also replaced the rear wings, while other designs utilized a prop rotor. During rotation the airfoils change pitch to produce varying amounts of lift and thrust, and both wheels rotate counterclockwise to null the torque produce by a motor mounted within the fuselage. During the upper and forward part of the rotation the airfoils are given positive pitch, and during the lowest part of the rotation the airfoils are given a negative pitch. Adjusting the pitch of airfoils can be mechanically controlled by an eccentric control ring located within the axis that is linked to each foil; this control ring is represented in green in the animation at left . The blue arrows represent the direction of thrust.

Though Caldwell had created a reasonable instrument to attain flight, he never cared to build an example. He moved on to ornithopter designs and securities fraud instead. Over the next decade, just a handful of cyclogyros were constructed. But not a single one was ever flown, and after wind tunnel tests proved that the power to turn the wheels was not feasible in 1935, no one even attempted to revive the idea.

That is until 2007. That year, a team of students at the University of Singapore constructed a working model of a cyclogyro. Advances in motor scaling have become the bridge over the threshold that kept cyclogyros a fantasy. Other engineering programs around the world followed suit, and the most advanced gyro to date would probably be the one developed by researchers at Seoul National University.

While no one is rushing the cyclogyros to the forefront of aviation, research into these flying machines has yielded valuable knowledge. Philip Bogrash is an inventor who has developed a cyclo wing (at left) that is an ellipse instead of a wheel. By elongating the air foil path along the horizontal, the airfoils are able to maximize their lift and thrust capabilities by minimizing the instances where the produce neutral lift and thrust. Operators are able to change the pitch of the airfoils for operating scenarios; one pitch can produce the fastest cruising speed, while another would allow near-silent operation.

Also, there is hope that those flying cars we've all been promised can be achieved through the use of airfoil wheels similar to those on a cyclogyro. While roadworthy, the iCar 101 positions airfoils within the inner rim of the tire. A video of it's modeled takeoff is available.

Currently, Bogrash and iCar 101 are seeking financers and modelers to help these inventions come to life. I hope for the sake of novelty that cyclogyros can become a reality. I feel as though transportation design always benefits from the extreme or impractical, and airliners and helicopters feel so 20^th century.

Resouces

(Image credits: German Car Forum; Supercharged; Wikimedia; Patent Docs)

Wikipedia - Cyclogyro; Jonathan Edward Caldwell

Automoblog - A Look Back: Cadillac Cien Concept

Museum of Retro Technology - The Cyclogyros