In the last year of my junior high school I had to prepare a final year project. The subject was free. So I decided to build an RC sailplane and write about it. At that time, at the age of 15, I had only built models from kits. But now I wanted to design this one on my own. As I had read a lot of articles written by Werner Thies and Karl-Heinz Denzin in the German “Mechanikus” and “modell” magazines, I had pretty clear ideas about the size and the shape of the model. The picture shows me holding the finished product.
I’m sorry that I can’t show a drawing of this plane, but it was lost. Also the model doesn’t exist any more. So I can only describe it from memory:
Wingspan: 1800mm (~71″)
Root chord: 200mm (~8″)
Tip chord: 150mm (~6″)
Wing section: Goettingen 613
Stab section: Flat bottom, 10% thickness
Stab area: 25% of wing area
Weight: 1200g (~42oz)
The fully sheeted wings were fixed to the fuselage with tongue and box. The elevator was initially covered with tissue.
But after the first crash it was fully sheeted for greater stability.
We already had a 3 channel Metz Mecatron radio. But the original receiver was damaged. So I built a new 2-channel RX from a kit offered by the “Reuter” company (doesn’t exist any more). This gave me perfect rudder control. The picture shows the radio installation: A 6 volt DEAC accumulator in the front, followed by the receiver and the Bellamatic servo. There was no elevator control.
The model flew very well and I had a lot of fun with it. At that time my father was a member of the FAG Kaltenkirchen and so I made most of my flights on their Moorkaten airfield. For high start we used 200m of fishing line. The high weight of the model was an advantage in the windy weather conditions of northern Germany.