Fifty swarming quadrocopters set world record at the voestalpine Klangwolke

The highlight of this year’s voestalpine Klangwolke in Linz, Austria, was a choreographed air show with 50 small helicopters equipped with LEDs (VIDEO).
Ars Electronica Futurelab and Ascending Technologies GmbH set a world record with this, because this was the largest swarm of these “quadrocopters” (so called because of their four rotors) outdoors at the same time.