Volocopter is stepping up flight testing of a prototype for its VoloCity eVTOL aircraft as it aims to meet its revised target of completing EASA type certification in 2025. The aircraft is now flying with its 18 new rotors as the German manufacturer and partners had to make some changes to the propulsion system for the two-seat model.

“We are now flying with type certification-relevant rotors, and we’ve done tests such as static loads, bird strikes and RPM [revolutions per minute] overloads,” Oliver Reinhardt, Volocopter’s chief risk and certification officer, told AIN. He said that following very extensive wind tunnel testing of the new rotors, the engineering team believes it is very close to getting them qualified with EASA.

As of early December, Volocopter was conducting between three and six flights each day, checking data from telemetry between each sortie before opening up the speed envelope to reach operational speed. “There is a lot of flight testing to come and [the schedule will be] very heavy in 2025,” Reinhardt said, indicating his team remains confident of completing type certification within the revised timeline.

Under EASA’s revised Special Conditions VTOL (SC-VTOL) rules, Volocopter and other eVTOL developers will be required to log 150 flight hours that earn certification credits, with 75 of these hours needing to be with a production-conforming version of the aircraft. Volocopter is preparing to have three aircraft flying in 2025.

Flight Control Software Ready for Motor Failure

While waiting for the VoloCity’s electric motors to undergo the required engine overhaul and inspections, the company switched its focus to flight control software updates. With the motors and new rotors back in the air, it has been able to conduct single- and dual-motor failure tests with the flight controls, which automatically make corrections without a pilot needing to intervene.

“[When a motor fails] you hear the other motors working more, but the aircraft continues to fly with now changes in attitude because the flight control system corrects and we have altitude hold mode set as a default,” Reinhardt explained. “It commands a specific nose-down angle instantaneously to compensate for any change caused by the loss of a motor.”

EASA officials visited Volocopter in mid-December to review the latest version of the electric propulsion system. Reinhardt reported that the company is on the verge of completing 75% of the third of four stages of audit required for type certification.

Five years ago, Volocopter became the first European eVTOL developer to gain design organization approval. As EASA becomes more comfortable with a company, it progressively reduces its officials' direct involvement in checking specific test results. Based on annual assessments of the company, the agency has reduced its hands-on involvement to 50% or less.

With the VoloCity’s type certification program now synchronized with the latest SC-VTOL revisions and means of compliance, Volocopter would appear to be on a stable course to completing the process required before series manufacturing can begin. “This is now stable and EASA can only force us to deviate from this if there is a clear safety reason,” Reinhardt explained.

Whether the VoloCity ends up being the first eVTOL model to achieve EASA type certification remains to be seen, but it would appear to be in poll position in the race as a new year begins. “We’ve paid more money for the lessons learned [as the first to start the process],” said Reinhardt. “The first mover always has to go the extra rounds and we’ve been feeling that, but our peers are nudging us to get over the finish line.”