In last month's installment, we discussed how one assembles rotors for autogyros. This month, we'll back down a little bit and look at a few nifty examples of RC autogyros to put the rather technical Part I installment into perspective. These autogyros and descriptions are courtesy of Rich Anderson of Gosport, IN.
The first thing you will notice is that most autogyros don't use tractor-type props (on the nose of the fuselage) as do conventional aircraft, but instead use pusher props mounted on engines installed on the aft side of the craft.
On the small side, this may be the first 1/2A-powered R/C Pusher Autogyro ever. This model has flown many times without incident and is very stable in all but the heaviest of winds. It is powered with a Norvel .061 swinging a 6x4 prop and will fly for nearly 10 min on 1 oz of 35% fuel. Rotor diameter is 30 inches and the craft weighs in at 15 oz.
Here's a somewhat larger design (called the ``Minnie-2'') that uses the conventional ``tractor prop'' scheme. This version has a rotor of 33 1/2'', weighs 30 ounces, and is powered by a Thunder Tiger .15 engine turning a Master Airscrew 8 x 4 prop. It is aptly controlled by a fully tilting rotor coupled directly by two micro servos.
Cierva C.4 - Steve Tillson's prototype R/C model of 1925 Cierva C4. It has a laterally tilting head for roll control. It uses OS .40 FP, throttle, rudder, elevator and lateral tilt and weighs just over 4 pounds. It has considerable flight experience, demonstrating simplicity of 3-bladed, flapping head with ability to make zero-ground-run landings in no wind conditions.
This is very same "DC Gyro" presented in the construction article of RC Modeler magazine, in the January 1998 issue. This is the gyro that started the Direct Control revolution (i.e. helicopter-like adjustment of the rotor head angle in flight. It has a 45'' diameter rotor and uses a .25 for power.