Recently, Airbus Group and Siemens signed an agreement in which they agreed to collaborate on hybrid electric propulsion systems. This is ground breaking, but should be seen in context – Airbus has been prominently displaying its tiny electric powered E-Fan aircraft at air shows for some time. In the noise and roar at air shows, this silent flier is easily ignored as it is not heard. But Airbus clearly has been thinking about this concept for some time.
The item that caught our attention was this: Tom Enders, CEO of Airbus Group said “We believe that by 2030 passenger aircraft below 100 seats could be propelled by hybrid propulsion systems and we are determined to explore this possibility together with world-class partners like Siemens.”
This is a level of detail that has not been disclosed before. It prompted a number of questions which we sent to Airbus Group, requesting their response.
- Can you explain the idea of hybrid propulsion systems?
In a nutshell, hybrid-electric propulsion systems employ two or more distinct types of power, for example power from an internal combustion engine (in the case of an aircraft, this would be using kerosene) and an electric motor. There’s ample material available online that goes into further details on hybrid propulsion, for example: https://en.wikipedia.org/wiki/Hybrid_vehicle
Hybrid-electric propulsion systems can significantly reduce fuel consumption of aircraft and reduce noise. European emissions targets aim for a 75 percent reduction of CO2 emissions by 2050 compared to the values for the year 2000. These ambitious goals cannot be achieved by conventional technologies. Other advantages of electric and hybrid propulsion?
- Lower noise level of electric propulsion: lower noise would significantly relieve airport residents – thus potentially allowing extending flight operation times and leveraging the capacity for increasing air traffic.
- Hybrid propulsion is the enabler to significantly reduce the emissions of CO2, NOx, and particulate – an all-electric aircraft would even cut in-flight emissions to zero.
- The vision of commercializing electric planes would significantly boost the industrial sector in the heart of Europe, in line with the Key Enabling Technology Roadmaps on European and national level.
Airbus Group and Siemens plan to jointly develop prototypes for various propulsion systems with power classes ranging from a few 100 kilowatts up to 10 and more megawatts, i.e. for short, local trips with aircraft below 100 seats, helicopters or UAVs up to classic short and medium-range journeys.
- Can you explain how such a hybrid drive system impacts traditional engines in terms of weight?
The impact will be different depending on the hybrid architecture. For example, in a serial architecture with separation of power and thrust generation and the potential implementation of a second energy source, the engines will only be used to generate shaft power. The weight of the core engine will be reduced while other functionalities will be distributed to other location on the aircraft – such as generator and e-machines for thrust generation. The overall propulsion system weight will increase, but the advantages gained with overall aircraft optimization will mitigate this weight impact and improve performance.
- The cut in fuel consumption is understood with its attendant cut in pollution. How much of a driver is cutting noise?
Reducing the overall environmental impact of aviation and air traffic is the goal of our E-Aircraft Roadmap – which is Airbus Group’s roadmap for the development of electric and hybrid technologies (see more details on the E-Aircraft Roadmap below). So the short answer is that we are targeting cuts in both fuel consumption / CO2 / NOx emissions and noise emissions with our R&D work into hybrid-electric propulsion.
A quick overview of our E-Aircraft Roadmap:
- Airbus Group and its global innovation network, Airbus Group Innovations, has developed the E-Aircraft (electric aircraft) Roadmap to target advanced technological breakthroughs that could be key enablers of its long-term goal to ‘electrify the skies.’
- In general, the E-Roadmap efforts done by Airbus Group Innovations and its partners are part of the aerospace industry’s research to support the ambitious environmental protection goals of the European Commission, stated in the “Flightpath 2050 – Europe’s Vision for Aviation”.
- Airbus Group’s E-Roadmap is focused on two pillars:
- The first one is related to the E-Fan project and its industrialization as E-Fan 2.0.
- Airbus Group and its partners are developing the industrial design of E-Fan 2.0.
- To facilitate the production of the E-Fan 2.0 as well as the commercialization, providing maintenance and services to the E-Fan 2.0 aircraft, the company Voltair SAS was founded and the location of the FAL (Pau) announced.
- The second pillar is the E-Aircraft System House located in Ottobrunn (Germany) at the Ludwig Bölkow Campus. Today, research operations are already being performed in the PowerLab 1.0 at Ludwig Bölkow Campus, and the extension of the PowerLab 1.0 to include the E-Aircraft System House has started.
- The E-Aircraft System House (groundbreaking in April 2016) is being developed to be established and will be extended step by step in the coming years. The PowerLab 1.0 as an initial testing facility is already in operation.
- The first one is related to the E-Fan project and its industrialization as E-Fan 2.0.
Working towards Flightpath 2050 / European Commission goals
- The efforts done by Airbus Group Innovations and its partners are part of the aerospace industry’s research to support the ambitious environmental protection goals of the European Commission, stated in the “Flightpath 2050 – Europe’s Vision for Aviation” report:
- Reduction of aircraft CO2 emission by 75%.
- Reduction of Nitrogen Oxides (NOx) by 90%.
- Reduction of Noise level by 65% – all compared to the levels of the year 2000.
- Customer orientation and market needs.
- Industrial competitiveness and maintain adequate skills and research infrastructure base in Europe.
- Besides research in the field of hybrid and electric propulsion, the group’s research activities focus on alternative fuels, such as algae for example. Just recently the construction work of the Algae Technikum at the Ludwig Bölkow Campus in Ottobrunn / Taufkirchen finished and the Technical University of Munich began research in Fall 2015.
- Airbus Group Innovations is doing research on potential future technologies, which could then be integrated in a commercial aircraft as needed.
- This would need a significant breakthrough in battery energy density for full electric aircraft and is not possible with state of the art technology today.
- How confident are you of having a sizable demonstrator by 2020?
The project has been launched with the target of demonstrating specific propulsion system architectures, feasibility and performance by a systems ground demonstrator. The project has also the target of ensuring early assessments through decision gates to down select or stop certain technologies or system architectures for planned potential applications and timely availability.
The goal of Airbus Group’s collaboration with Siemens is to demonstrate the technical feasibility of various hybrid/electric propulsion systems by 2020. Both companies will be making significant contributions into the project and have sourced a team of around 200 employees to advance European leadership in innovation and the development of electrically powered aircraft.
Electric and electric-hybrid flight both represent some of the biggest industrial challenges of our time, aiming at zero-emissions aviation. The progress we have achieved in this arena, together with our industrial and governmental partners, in only a few years is breath-taking, culminating in last year’s channel crossing of our all-electric E-Fan aircraft. We believe that by 2030 passenger aircraft below 100 seats could be propelled by hybrid propulsion systems and we are determined to explore this possibility together with world-class partners like Siemens.
- Why would <100-seaters will have this solution first?
Our R&D into hybrid and electric propulsion takes a multi-pronged approach to the development of viable hybrid and electric propulsion systems. For example, it includes different power classes (for different aircraft concepts and sizes) and system architectures to support all potential future products.
Airbus Group and Siemens plan to jointly develop prototypes for various propulsion systems with power classes ranging from a few 100 kilowatts up to 10 and more megawatts, i.e. for short, local trips with aircraft below 100 seats, helicopters or UAVs up to classic short and medium-range journeys.
Airbus Group has been gathering operational experience with electrically powered aircraft since 2014 with the E-Fan, a full electric two-seater dedicated to training pilots. This success has been achieved together with various industrial partners and steadfast support of the French government.
Airbus Group intends to accelerate with the extended capabilities of the planned
E-Aircraft System House at Ottobrunn/Taufkirchen site the development of components and system technologies.
Siemens is determined to establish hybrid-electric propulsion systems for aircraft as a future business. The partners have agreed to collaborate exclusively in selected development areas. In parallel, both partners will continue to work together with their current partners for small airplanes with fewer than 20 seats.
- Approximately what level of power would be needed for such an aircraft?
For a regional aircraft, we would anticipate a propulsion system with overall performance / power output of around 6 – 10 MW overall – the power needed would of course be dependent on an individual aircraft’s specifications and top-level requirements, e.g., detailed maximum passenger numbers and weight, , mission, cargo volume and weight, etc. …)
- Can we assume this solution will be deployed at ATR first then?
As mentioned previously, the first step is to demonstrate the feasibility and performance of a hybrid-electric propulsion system according to a specific set of potential aircraft applications. Following the successful completion of these demonstrations, we’ll proceed with determining which initial applications we could envision using this technology for.
