A few years back I designed a scale model of the Lockheed AH-56 Cheyenne, probably my favorite helicopter of all time. The experimental Cheyenne featured a variable-pitch pusher prop and small wings, which allowed it to fly much like an airplane and gave it a top speed of nearly 250 MPH. My Cheyenne was based on Align T-Rex 450 hardware, with many customized components to allow it to fit in the slender fiberglass fuselage. The project turned out really well, and I was particularly honored that this little model was awarded first place in the helicopter class at the 2011 Toledo Weak Signals show. My only regret for the Cheyenne was that I didn’t make it bigger. This year I decided it was time to do something about that.
For my larger Cheyenne I’ve settled on Blade 600 X mechanics, “stretched” to 700 size with a longer tail boom and 690mm blades. This will result in a 1/10 scale model 65″ long. As the preliminary line drawing shows, this machine is going to dwarf the previous version.
I drew the fuselage for the Cheyenne in Rhino 3D, which allows me to verify fit for all components. This 3D model will be used to machine a foam plug, which will then be glassed, finished and waxed so that it can be the master for a female fiberglass mold.
The scale airframe is certainly the star of any scale build, but on a project like the Cheyenne my first priority was to get the mechanics built and test flown. After all, the complex tail unit, with its outrigger tail rotor and variable-pitch pusher prop, is the key to the entire project, so that’s a natural place to start. So let’s set the body aside for now and move on to the mechanics….