They have come a long way from their flying Zumba-ball days [0,1] [0] https://upload.wikimedia.org/wikipedia/commons/2/2b/E-volo_erstflug.jpg https://upload.wi

They have come a long way from their flying Zumba-ball days [0,1] [0] https://upload.wikimedia.org/wikipedia/commons/2/2b/E-volo_erstflug.jpg https://upload.wikimedia.org/wikipedia/commons/2/2b/E-volo_e... [1] https://en.wikipedia.org/wiki/Volocopter https://en.wikipedia.org/wiki/Volocopter