My intention was to design a plane up to 3 m wingspan without strengthening by carbon tubes - that means 100% printed.
But I had to stop at 1,35 m because the wing reached already a weight of almost 1,1 kg. My small motor which I used already on my sail plane https://cults3d.com/en/game/first-take-off-of-a-fully-printed-fdm-sailplane wouldn't last for much more weight.
Additionelly I thought a flying wing would make less problems to get the CG forwards, because of the short tail. But again I got the same trouble. The big mass of the wing pushed the CG backwards, so I was forced to add a spacer on front. This makes the plane looks a bit like a duck ;-)
Nevertheless I fasten the wing ends just with tape to have the ability to extend the wing span at any time.
Uli Richter - a long standing pilot of the Lufthansa and very experienced in building and flying air plane models - was so kind to fly my wing plane. He had absolutely no problems and showed us immediately a fully acrobatic flight show. Thank you very much for the wonderfull flights!
It was not so easy to follow with the camera all the unexpected maneuver in flight. Therefore the video can't give by far the impression as it was in reality.
wing span: 1350 mm
wing chord: 336 mm
aerodynamic center: 78.1 mm
aerodynamic center 5% stability: 61.3 mm
wing profil: Clark YS
wing overall weight: 1100 g
wing area: 45,36 dm²
fuselage overall weight 680 g
wing loading: 39,2 g/dm²
longitudinal stability (Thies) STFs: 45,4
motor: Robbe Roxxy BL Outrunner 2834-08
propeller: Aeronaut CAM 10 x 6”
static thrust: 1100 g (3S Lipo)
Print and Material
print time wing: 81 h
print time fuselage: 35 h
used PLA: 1.4 kg
"fuselage 02 brim.stl" replaced by "fuselage 02 mod brim.stl"
The lower edge of the border is rounded for easier printing.
The next days I will give more information.