GRAPHITE

 

Me, Graham, with my Graphite on Ivinghoe Beacon

The Graphite is an own design all carbon fibre model about 60" (1.5m) span for close-in tight aerobatics. I made the fuselage using the Lost Foam Method and two layers of Carbon fibre braiding.

Briefly, for those of you not acquainted with the lost foam method, you 'simply' carve and sand a fuselage to shape from blue foam, wrap it in parcel (packing) tape and cover the outside of the foam fuselage with cloth and epoxy resin or in my case carbon fibre woven sock. When the resin is cured the foam is dissolved away with Acetone.

 

Intended to be a lightweight aircraft, I chose a section that I thought suitable - the RG 15. With hindsight, I should have chosen a profile with better negative performance than the RG 15 since inverted manoeuvres with my Graphite need to handled carefully, my being used to a model with better performance in this area. I had the wings and sailplane cut for me by one of the specialist firms around. The skins are of 25 gsm glass cloth and 100 gsm plain weave carbon fibre cloth vacuumed on to Dow Styrofoam I.B. blue foam.

 

For the controls I have an all moving sailplane, ailerons, rudder, thermal flap and elevator-coupled flapperons for square aerobatics. I used Graupner 3341's for the rudder and elevator and a pair of the newish Multiplex FLBB 11mm thick servos for the ailerons. When the wind is light I use a small catapult to launch to well over 100 feet on the slope.
 

Catapult launching...
 

Nosehook for catapultThe catapult is made of four lengths (4 x 12 ft) of black synthetic bungee rubber tubing (8mm) and a short length (15ft) of monofilament line, hooked right on the nose, and boy, does it go! Oh yes, the 4 second catapult launch. Here it is from quite a few years ago!

 

bungeee.mp4