Video of EV1 (1975)

Testing of all driving functions was only possible with existing wing lift. Therefore, test runs were necessary at first. Particularly the switch between gliding and powered flight had been tested thereby.

1st flight:

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

2nd flight:

The second flight, too only lasted a few wing beats.

Both flights looked somewhat miserable at first sight. However, relief was huge thereafter. There were no vertical movements of the fuselage. Furthermore, the novel crank drive drive worked very well. Its switch between powered and gliding flight worked flawlessly. Further short flights could be executed.

Video of EV4 (1979)

Though the powered flights took somewhat longer now, all in all only about five flights had been completed - a little sparse for the work in years. But there had been 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,
• the change to powered flight with a cardan gear mechanism,
• the slight bobbing up and down of the fuselage with a flapping cycle of about 0.8 s
• and after some wing flappings the change to gliding flight.

The flight speed obviously isn't big enough for a normal gliding flight thereafter. Therefore, it changes to a sinking flight.

Scene 2

• a start to a gliding flight on a slope again and
• two transitions between gliding and powered flight.
• The second switch does not happen speedily, most likely due to the indecisiveness of the radio-control pilot.

In both flights the varying acceleration in both wings' working cycles is clearly to be seen at the rhythmically alternating distance between the model and marginal image border.

Video of EV7a (1990)

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

 

Scene 2: In this powered flight the cyclical changes of the wing twisting is clearly to be seen.

 

Scene 3: With a length of about one minute it shows one of the few longer flights. In particular, one can see:

• 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.