Against the backdrop of climate change, the aviation industry is increasingly becoming the focus of debate in wider society. Innovations geared towards more environment-friendly air transport are becoming more prevalent. The German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt; DLR) presented its expertise and research work relating to alternative fuels, electric flight, uncrewed flight and atmospheric research at the German National Aeronautics Conference on 21 August 2019 in Leipzig. The DLR research aircraft HALO and Do 228 (D-CFFU), and the flying helicopter simulator EC-135 FHS were there.
“Essentially, we believe that the aviation sector has two main tasks. Firstly, to improve current aircraft, because they are going to be flying for some time to come, and secondly, to pave the way for new aircraft,” says Rolf Henke, DLR Executive Board Member for Aeronautics Research. “With present-day aircraft, a lot remains to be done in terms of aerodynamics, weight, propulsion and synthetic fuels. In terms of tomorrow’s aircraft, there is still a great deal of research work that needs to be carried out. Electric flight has a huge potential for reducing noise and pollution, and can make environment-friendly flight possible on short- and medium-haul routes. Our vision is a ‘zero-emission aircraft’.”
‘Electric Flight Demonstrator’ conceptual design
Hybrid electric propulsion systems are a key technology and vital precursor to the realisation of electrically powered flight. They offer the potential to significantly reduce emissions of carbon dioxide, nitrogen oxides and noise on the way towards a ‘zero-emission aircraft’. In future, electric propulsion systems will be used both in urban air mobility and for commuter aircraft, thus enabling new aircraft configurations. Previously, only small, battery-powered aircraft have been in operation, with small, hybrid-electric aircraft undergoing flight tests. However, DLR is now working with industry partners Siemens1, MTU Aero Engines and RUAG Aviation to prepare a feasibility study for a 19-passenger test aircraft based on a Dornier Do 228.
The study shows that there are good prospects of success for converting and testing a national ‘Electric Flight Demonstrator’ with a completely electric propulsion system in the 500-kilowatt power class. The development stages would be battery-powered flight and hybrid-electric operation with an additional gas turbine generator. This test platform – the size of a commuter aircraft – will facilitate extensive research and further development of hydrogen as an energy source. This will increase the potential of electric flight to achieve a fair environmental balance when flying on short- and medium-haul routes. The Do 228 D-CFFU, which DLR uses for Earth observation research, showed the size of such a test aircraft at the German National Aeronautics Conference, in the form of a special display.
Uncrewed and crewes flying as a team
The aircraft of tomorrow will also include uncrewed aerial vehicles. The sector is currently experiencing rapid growth, along with the emergence of novel concepts and technologies. New ‘urban air mobility’ is resulting in the potential for air transport in and between cities. However, these new elements of the air transport system pose an enormous challenge when it comes to managing lower-level airspace. DLR is making the research infrastructure necessary for addressing this problem available to its partners in the form of the new National Experimental Test Center for Unmanned Aircraft Systems in Cochstedt, near Magdeburg. In the autumn of 2018, DLR Cochstedt conducted a test in which the DLR EC 135 FHS and an uncrewed superARTIS light helicopter flew in formation, as is required during reconnaissance flights following natural disasters. Both aircraft were on display at the conference to showcase the research topic of joint crewed and uncrewed flight. Last year, superARTIS also demonstrated the uncrewed delivery of relief supplies in the Dominican Republic.
Further information, images and contacts you will find on DLR's press release: DLR presents its work at the German National Aeronautics Conference: Research into climate-neutral air transport.