Rolf Henke, DLR executive board member responsible for aeronautics research and technology, said that “this joint research-industry project is the first of many steps toward zero-emission aviation.” MTU chief operating officer Lars Wagner claimed: “As things stand today, fuel cells utilizing sustainably produced hydrogen offer the greatest long-term potential for realizing emissions-free aviation.” Especially true for regional, short- or medium-distance aircraft. The Do-228’s maiden flight could take place in 2026.
Since the beginning of 2020, a 45-member group led by Johannes Hartmann – EXACT, Exploration of Electric Aircraft Concepts and Technologies – has been working on new efficient, eco-friendly commercial airplane technology at the DLR Systems Engineering Institute. Researchers from 20 different DLR organizations aim to bring a 70-passenger aircraft with a 2,000-kilometer range to technological maturity by 2040.
Pascale Ehrenfreund, who left the DLR in late September 2020, originally proposed devising this integrated concept for eco-friendly aviation. It is not clear yet if her successor, Anke Kaysser-Pyzalla, will announce an even more ambitious goal.
To achieve their goal, EXACT researchers are drawing on expertise in zero-emission aeronautics at the DLR Institute of Engineering Thermodynamics. The institute developed both the Antares DLR-H2 (see HZwei, January 2013) and a four-seat passenger aircraft dubbed HY4, (see H2-international, February 2016 and March 2017). The latter emerged from a collaboration between DLR spin-off H2Fly, Slovenian aircraft manufacturer Pipistrel and Cummins.
A sixth-generation fuel cell engine, powering the latest HY4 model, was designed by Josef Kallo, Ulm University professor, and his team. Despite the difficult circumstances, not least due to Covid-19 regulations, the H2Fly’s plane take-off on Nov. 6, 2020, in Mariboa, Slovenia, was quite a success. Kallo told H2-international: “The system really packs a punch.”
His team’s perseverance kept the project going despite several delays, including the first flight’s postponement from October to November. Following a three-month quarantine, team members completed a total of 32 take-offs in four days in bad, extremely foggy weather with visibility under 1,000 feet (300 meters), sometimes flying for two consecutive hours.
In late 2020, the HY4 received a test flight permit for Stuttgart. Walter Schoefer, Stuttgart airport management company, FSG’s board spokesperson, called it a “great milestone” for the biggest project FSG had ever supported. During the Nov. 11 HY4 presentation at Stuttgart airport, Winfried Hermann, Baden-Württemberg’s state transportation minister and FSG chairman, lauded Kallo and his team for their profound commitment and tenacity.