Electric aircraft – establishing a baseline
New technologies and innovation need to start somewhere.
Embracing new technologies in aviation often starts with sailplanes. You may ask why. Well, as with most aspects in innovation, not everything works as planned and if you want to test a new fuel system, what better way to start than to try this first with a sailplane. If it works during testing, great! If It doesn’t, a sailplane can always fall back on its ability to ‘sail home’. Safety is key.
Electric engines for sailplanes – complying with safety requirements
The first steps towards certification for an electric powered sailplane were taken in 1995 with Germany’s Luftfahrt-Bundesamt (LBA) as responsible National Authority. EASA formally took over in 2003, with the LBA remaining in charge of the technical tasks related to the aircraft, while EASA handled the engine.
Existing certification specifications for sailplanes (CS-22) at that time did not cover or allow for a sailplane to have an electric propulsion system installed, and as is usual with any changes in specifications, EASA and the LBA first had to establish whether this would be in line with the necessary requirement to ensure aviation safety, meaning ‘Would it be safe to fly?’.
Special Condition - requirements for an electric propulsion system
In 2006, Experts from the Certification Directorate at EASA put together requirements for an electric propulsion system and consulted with stakeholders in the aviation industry who were able to scrutinise the requirements and give direct feedback to EASA. Following the consolidation of all comments, EASA was in a position to issue the special condition that complements CS-22 to establish a complete certification basis.
- If you are interested in the technical information, check the related consultation on EASA Pro published in 2006.
Special Condition – design features for installation
A second consultation was needed to look at the design features for the installation of an electric propulsion system on a sailplane within the EASA framework. What energy storage devices would be safe to use? Rechargeable batteries, other different energy storage technologies such as fuel cells or capacitors, or hybrid propulsion systems? Again, EASA’s experts consulted with the aviation industry on the requirements and in 2014, the second step was completed.
- Check the consultation on EASA Pro for more information.
Final step – updating the regulation
As soon as the technology for electric propulsion systems and their installation reach a stable level, a change in the European regulation can be launched. As with all changes to existing or new standards for aviation safety, EASA will publish an Agency Decision on this.
- Have a look at the Sailplane Rule Book – Easy Access Rules for more information.
Current state of play
A number of electric propulsion systems for sailplanes are now available, and manufacturers will see an increase in demand. In Europe, the segment for this market has three main systems for electric propulsion systems, all certified by EASA and safe to use.
Meanwhile the aviation industry and research institutes are looking at even newer technologies, such as Hydrogen or Biofuels, to asses whether they could offer a way to ensure the engine powered sailplane industry remains sustainable.