Video of EV1 (1975)

Testing of all driving functions was only possible at existing lift on the wing. Therefore, first run tests was necessary. Particularly thereby beeing tested switching beween gliding and powered flight.

1st flight:

There is to be seen starting to the first powered flight of an electrically driven flapping wing model.

2nd flight:

Also the second flight takes only a few wing beats.

At first both flights looking miserable. However, after that relief was huge. There were no vertitcal movements of the fuselage. Furthermore the novel crank drive worked very well. His switching between powered and gliding flight worked flawlessly. Further short flights could be executed.

Video of EV4 (1979)

Now sometimes the powered flights take longer, but all in all there only has been absolved about five flights - somewhat less for the work in years. But there are just too many ideas for further improvements.

Video of EV6 (1983)

shows two short flight sequences.

Scene 1

• a launch to gliding flight on a slope,
• a change over to powered flight with a cardan gear mechanism,
• slight bobbing up and down of the fuselage with a flapping cycle of about 0.8 s
• and after some wing flappings the change over to glide.

The model hasn't enough flight speed for a normal gliding flight, therefore it goes to a sinking flight.

Scene 2

• a start to a gliding flight on the slope again and
• two changings between gliding and powered flight.
• The second switch over is not uninterrupted. This is probably because the radio-control pilot was not enough resolute.

In the fly by situation of both flights the different acceleration in both work cycles by the rhythmically alternating distance between the model and the side of the frame is good to be seen.

Video of EV7a (1990)

Scene 1 shows a short powered flight with a changing to gliding flight. Thereby was used a rack-and-pinion drive system with electronic switching.

 

Scene 2: At this powered flight the cyclical changing of wing twisting is good to be seen.

 

Scene 3 with her length of about one minute it shows one of the few longer flights. Especially there is to seen:

• a high start to a height of about 10 meters,
• a changing from gliding flight to powered flight with a rack and pinion drive unit,
• the relatively slow stroke motion with a flapping cycle of
  about 1.1 s,
• nevertheless there is only to be seen a little bobbing up and down of the fuselage,
• a horizontal flight over a longer distance without upcurrent from a slope or thermal and
• the result of the breakdown of lift and thrust due to stalling after a short climb.
  For details please look at Flight stability of ornithopters.