Silent flight
Daniel Zahn
For Konstantin Kondak, electric mobility gives an unexpected twist to a conventional trip. “With new technologies, flying becomes a guilt-free pleasure,” says the roboticist and electric aircraft developer happily. Together with the experienced aircraft engineer and e-flight pioneer Calin Gologan, Kondak leads the DLR spin-off Elektra Solar. There, 12 employees are working on solar-powered electric aircraft. Their latest coup is the Elektra Trainer, which has now gone into series production. Like its 'family' members, it is energy-neutral as it flies and as quiet as gentle rain.
The Elektra Trainer is an electric-powered aircraft of the German ultralight class that can be flown semi or fully autonomously – ideal for training pilots. It received its certification as the first electric ultralight motor aircraft in Germany at the beginning of 2023. But it is not just about taking nice leisurely trips; it is about shaping a new era of transportation and securing a leading global position.
Alongside working on traditional aviation topics, the company is utilising technologies from robotics and spaceflight. Elektra Solar emerged as a spin-off from the DLR Institute of Robotics and Mechatronics in Oberpfaffenhofen in 2013, and was founded by former institute director Gerd Hirzinger, Calin Gologan and Konstantin Kondak. Kondak, a researcher heading the DLR Flying Robots research group, was eager to turn theoretical knowledge into practical applications, and the joy of doing so still drives him today. His vision? To transport people via electric air taxis.
Fancy a city trip?
Elektra Solar
In the autumn of 2023, Elektra Solar's long-endurance two-seat electric aircraft flew 313 kilometres from Oberpfaffenhofen to Bern, as part of a demonstration using electric power alone. With a range and flight time of three hours, destinations such as Venice, Vienna, Strasbourg, Frankfurt and Prague were within reach. The e-plane coped well with bad weather and could have completed the entire flight autonomously, ending with a precise landing. The algorithms for safe and efficient autonomous flying, developed in collaboration with the DLR Institute, are a crucial component in the air taxis of the future. The pilot assistance system installed in the Elektra Trainer already uses this sophisticated software.
"A robot on the ground can simply power down if it faces any issues. That is not an option in flight," explains Kondak. The systems must reach very high safety levels, which is essential for the future of electric passenger transport.
The Elektra Solar team have come up with a special feature for sustainable operation: their Elektra Trainer includes a transport trailer that can be equipped with solar cells. This mobile charging station can provide around 400 flight hours per year and doubles as a 'garage', sparing flying enthusiasts the expense of scarce hangar spaces.
Elektra Solar
A growing industry leader at the cutting-edge
The small company from Landsberg am Lech has, rather unusually, grown of its own accord. Manufacturers of ultralight aircraft usually have the backing of a financially robust consortium to cushion the company in case of extended development times. So, what is the secret of Elektra Solar's success?
Christian Rudnik
A key factor is Elektra Solar's innovative strength, which is fuelled directly by research. Even after a decade, the spin-off maintains close ties with the DLR institute it grew from. Kondak divides his time evenly between Elektra Solar and DLR, and some of his employees also work part-time in Landsberg and Oberpfaffenhofen. Collaborative projects have expanded the expertise of both the company and DLR. "It's a win-win situation," says Kondak. "We develop technologies together, promptly constructing corresponding aircraft in the company, while the institute gains unparalleled expertise."
It's a collaboration that addresses social challenges right at the cutting edge, as Alin Albu-Schäffer, Director of the DLR Institute of Robotics and Mechatronics, points out: "I am very pleased that our mechatronic drive development is finding such a broad field of application and can thus contribute to greater sustainability in aviation." Currently, the Institute and Elektra Solar are collaborating on the development of a new propulsion system. The start-up will further develop this for four to six-seater electric aircraft for commercial passenger transport. The project is embedded in the Bavarian aviation research programme 'Holistic Air Mobility Initiative Bavaria'. Elektra Solar will make use of the scientific results and feed them directly into the economic cycle.
Making normal tomorrow what's unique today
Elektra Solar
"The conditions at DLR are unique when it comes to turning business ideas into reality. All that is needed is determination and to act decisively," continues Kondak. With support for this provided by DLR's Innovation, Transfer and Research Infrastructures division, Kondak hopes that spin-offs and collaborations will be seen as commonplace in the future, not something special: "Scientists should be offered spin-offs as a career path right from the onset. Once they have achieved a PhD or become a group or department head, spin-offs should be a standard option." Not interested in financial support, Kondak puts more emphasis on providing the information and motivation to take that step of founding a spin-off.
Elektra Solar's success story began with solar-electric stratospheric aircraft and has now established a new benchmark for electric-powered aircraft with the Elektra Trainer. Should air taxis and affordable broadband via high-altitude platforms become commonplace in the future, Elektra Solar aims to be at the forefront. Kondak, together with his colleagues, has been committed to this mission for over a decade as an entrepreneur and more than 20 years as a researcher – and they have plenty of ideas and passion for the coming decades.
The Elektra Solar fleet
In addition to the Elektra Trainer, Elektra Solar has developed other concepts.
ELEKTRA ONE: The predecessor of the Elektra Trainer. The electrically powered single-seater made its maiden flight in March 2011. It mastered an Alpine overflight in summer 2015 as a special challenge.
ELEKTRA TWO: The solar-powered high-altitude platform has a wingspan of 27 metres. It can be flown manned and unmanned.
ELEKTRA VTOL: The electric VTOL drone with gimbal camera and two hours of flight time has a wingspan of 2.5 metres. Camera data is processed in real time by an 'algorithmic pipeline' in the cloud.
An article by Bernadette Jung from the DLRmagazine 174