E-volo’s 18-rotor electric Volocopter makes maiden flight
By Heidi Hoopes
November 21, 2013
E-volo recently celebrated the maiden launch of its electric two-passenger, 18-rotor VC200 "Volocopter," touting the vehicle's safety and simplicity after an indoor flight inside the dm-arena in Karlsruhe, Germany on November 17. While the copter is similar in form to both quadcopters and helicopters, the company resists the helicopter label, pointing out the numerous radically different safety and design choices that set the vehicle apart.
Following on from earlier prototypes, the overall design resembles a quadcopter – or, more aptly with its 18 separate rotors, an octodecacopter. On the Volocopter, six arms extending from the central part of the rotor ring split into twelve more arms, with rotors placed at each juncture.
For power, six battery blocks power the rotor drives for about twenty minutes of emission-free flight time, with an hour anticipated in the future. Additionally, range extenders are envisioned for the final design. The team is aiming for a cruising speed of at least 54 knots (62 mph / 100 km/h) and a flight altitude of 6,500 ft for the production version.
E-volo emphasizes the redundancies in the battery system. Each rotor arm is powered by three batteries, so two nonadjacent batteries could fail and the Volocopter could still land safely. In even more dire straits, a ballistic separation system deploys a parachute.
These measures are a part of e-volo’s larger goal that the “Volocopter must become the world’s safest piece of air sport equipment.” Pointing out that most helicopter emergencies stem from pilot behavior, e-volo designed the Volocopter with onboard computers sensors that assume the role of determining and compensating for flight conditions, while the pilot “merely” controls the direction. Because of this design decision, the Volocopter is also easy to fly and pilot training is simpler.
Finally, the electronic systems of the Volocopter are different from traditional designs. Instead of the classic fly-by-wire computer systems, the Volocopter has twenty independent computers which could theoretically each fly the computer solo.
The team conducted multiple remote-controlled flights lasting several minutes each under the dm-arena's nearly 22 m (72 ft) ceiling. E-volo hoped to test several things during the VC200’s launch. Even in simulations it was impossible to predict if the lightweight carbon construction would produce vibrations, which can be annoying and loud, or even deadly. However, no vibrations were evident, even through the HD camera mounted on the exterior rotor ring.
Additionally, though previous tests had shown that the overall noise level would be quieter than a traditional helicopter – not a difficult feat to be sure – the team was still surprised that the vehicle were quieter than expected and had a pleasant rich sound.
The overall flight was several minutes long and included several takeoffs and landings. Highlights of it can be watched in the video below.