The design concept has switched to a more conventional tailed design. New images have been added showing the configuration. This was done because, although we think the it would have flown, the tailless aircraft would have been about 10 lbs heavier than a tailed aircraft. The extra weight would have been needed to give the tailless aircraft’s swept wings, which are relatively narrow, adequate torsion stiffness. A tailed aircraft can use unswept wings which are subjected to a much smaller torques and the tail itself doesn’t weight much. The span is still 78 feet and the empty weight is currently targeted at about 62 lbs.
We were able to test the strength of our wing joints thanks to Milo Clauson at Oregon State University. A titanium coupler joint was subjected to a 3-point bend equivalent to a 3g load on our aircraft. It suffered no damage or fatigue and the tested joint will probably end up on the final aircraft.
The fuselage and propeller design is complete, pending wind tunnel verification of their desired aerodynamic performance. Our propeller should operate at 89-91% efficiency despite the fact that its 1 meter radius is relatively small for human-powered aircraft. We have nearly finished constructing prototype wheels for the aircraft. We decided we could construct our own disc wheels lighter (and considerably cheaper) than bicycle wheels available off the shelf. There is some warranted concern is that they may be too flimsy; we prefer to think of this as knowing they aren’t too heavy. We’ll post pictures when the wheels are finished.
If you haven’t already seen them, I highly recommend watching the recently released videos of the University of Toronto’s human-powered ornithopter. It is called the Snowbird and the flapping wings make the aircraft extremely graceful. It’s all the more impressive when you consider that the first manned, engine-powered ornithopter flew in 2006. Here are links to both their website and flight videos.








