The Special Condition That’s Powering eVTOL

Safran Electrical & Power was awarded the first type certificate for an engine that complies with Special Condition SC E-19, which it believes to be the world’s first Special Condition for electric and/or hybrid propulsion systems. The certification of the ENGINeUS marks the successful conclusion of an eight-year journey from the perspective of the European Union Aviation Safety Agency (EASA).

The electric ENGINeUS 100 series is starting with the B1 model now certified, initially planned for installation on a two-seater aircraft. The aim is to extend the series to a greater power range (from 89 KW to 180 KW), a baseline to allow for wider application in up to 19-seater aircraft.

For EASA, the certification process in this case brought learnings that can be applied to further propulsion projects in the future.

“This was a fascinating project for EASA, and the first test of our Special Condition designed for the certification of hybrid and all-electric propulsion,” said Rachel Daeschler, EASA Certification Director.

Back in 2017, EASA initiated discussions on regulation evaluation for a wide spectrum of propulsion systems. A number of requests for the type certification of novel designs were coming to EASA, mostly for General Aviation and vertical take-off and landing (VTOL) aircraft. The manufacturers variously had the ambition to enable Urban Air Mobility (UAM) or create new solutions for Regional Air Mobility (RAM). Electric or hybrid engines, as well as the diversity of new propulsion system architectures proposed, were not foreseen when the specifications for the conventional thermal engines were originally developed decades ago. A new electric engine could not therefore be certified directly against these specifications.

To fill this gap, EASA developed what is known as a Special Condition (SC). The objective was to allow clearly needed innovation for sustainability, while ensuring the same safety record as today’s thermal engines. The aim was to support propulsion certification with a unique performance-based requirement applicable to both aircraft and engine certification applications, so as to guarantee consistency from the outset.

SC E-19 for the certification of hybrid and/or electric propulsion was published in April 2021. It was then implemented as the certification standard for VTOL applications and to the first propulsion type certificate application from a new company associated with a larger group, Safran.

As a result of the strong cooperation between Safran and EASA, the certification of ENGINeUS 100B1 required a similar time investment as for a rotorcraft turboshaft engine: less than 2 years. In parallel to the engine certification, the engine racked up more than 100 flight hours on prototype aeroplanes.