I have always thought that autogyro aircraft are really cool. Just the fact that how they fly is different in a sense than either a helicopter or an airplane is really intriguing. You might be wondering what an autogyro is?
An autogyro is a rotorcraft that does not power the rotor blade directly through engine torque but rather the rotor is made to spin by air passing up through it in much the same way as a wind turbine is powered by the wind. Helicopters are different - where the rotor is usually driven by a drive shaft and as a result needs some method to counter the torque such as a tail rotor. By having an unpowered rotor blade the autogyro needs some means of propulsion, such as a pusher prop in the rear to push it through the air.
There are a couple of really cool examples of gyrocopters both scale as well as in RC form. First off there is the Hobbyking Auto-G2 which is a really great little aircraft that can be bought for around $100 or so and features an auto-start system that gets the main rotor turning beforehand.
Photo courtesy of HobbyKing.com
Take a look at the Auto-G2 on HobbyKing's website here: https://www.hobbyking.com/hobbyking/store/__43343__Durafly_8482_Auto_G2_Gyrocopter_w_Auto_Start_System_821mm_PNF_US_Warehouse_.html
Another really awesome example of a Gyrocopter is a real scale version that is setting all kinds of records for speed and pushing the envelope in many other ways. It is the Carter Aviation CarterCopter. This little gyrocopter looks a lot like the little jet many know from the James Bond movie, the Beede BD-5J.
Photo courtesy of Cartercopters.com
As you can see, they look rather similar in a way, or at least when I first saw the CarterCopter, the Beede was the jet that came to mind. If you have a change to take a look at the CarterCopter, I think you will be as intrigued with it as I was. They also have tons of information on their website on the project as well as press releases that have lots of really great information about gyrocopters in general.