Safran’s Electric Taxiing System could help carriers reduce both fuel costs and environmental emissions. The Paris-headquartered company clearly sees China as one of its biggest potential markets
In July, it was announced that Safran Landing Systems and China Aviation Energy and Emissions Solutions (CAEES), a subsidiary of China Aviation Supplies Holding Company (CAS) that specialises in energy and environmental technologies for the aviation industry, had signed a memorandum of understanding (MoU) to jointly promote electric taxiing solutions in China. The deal represents another step forward for Safran as it looks to advance its design for aircraft pushback and taxiing.
Safran’s Electric Taxiing System (ETS) is designed to enable commercial aircraft to taxi without having to use their own jet engines or a tow tractor. Using electric motors installed in the wheels on an aircraft’s main landing gear that are powered by the aircraft’s own auxiliary power unit (APU), the pilot has total control over the aircraft’s speed and heading during taxiing. Safran’s expects its ETS to offer savings on fuel costs of up to 4% per year, while also significantly reducing harmful emissions and avoiding the need for tow tractors to be available on a stand for pushback.
As part of the agreement, the two partners will present the technology to Chinese airlines. CAEES is also to provide support for the analysis of Chinese airport ramp operations and the regulations applicable to Chinese airports, helping in the effort to assess the potential benefits of ETS in the huge Chinese aviation market. The agreement will also enable the partners to evaluate the potential environmental gains and to study ETS in relation to Chinese CO2 emission quotas and local subsidies.
“The boom in Chinese air traffic has resulted in strong demand for airplane operations, including quick turnarounds, more taxiing, greater airport congestion and increased carbon emissions,” explains Zhang Xiaoshi, managing director of CAEES. “That’s why we want to carefully evaluate the expected benefits of electric taxiing for Chinese airlines.”
“This strategic partnership with CAEES… will facilitate our discussions with and access to the different players in the Chinese aviation industry,” informs Vincent Mascré, CEO of Safran Landing Systems. “Being more familiar with their expectations will help us refine our system’s capabilities in order for us to offer a product that meets operational requirements in this part of the world.”
Christophe Devillers, vice president electric taxiing at Safran, explained to Airside the particular benefits of ETS, and what stage of the programme the company has now reached. “We are currently progressing towards TRL6, which means that we are demonstrating the performance of the system under representative environmental conditions. This will be the final step of maturity before programme launch,” he observes. Entry into service is planned for 2021.
“Today’s turbofan engines are optimised for flying, not for moving aircraft on the ground,” he continues. “Every time an airliner taxis, it burns a disproportionate amount of fuel between the gate and the runway. ETS allows an aircraft to taxi without using the main engines, which obviously leads to a reduction in the emission of pollutants such as NOx, CO and CO2 which are a direct result of fuel burn in an engine.
“An independent report conducted by Envisa, a global environmental consulting company specialising in sustainable aviation, clearly showed that ETS can be an important contributor to reducing aircraft ground emissions by introducing cleaner electric taxiing operations. The report stated that ETS could reduce NOx emissions by up to 51%, CO emissions by up to 73% and CO2 by up to 61%. These reductions equate to real environmental benefits – the equivalent of planting up to 948 trees for CO2 savings, and eliminating 932 cars for NOx reductions. And that’s not to mention the reduction of noise near the gates,” Devillers insists.
“The fuel saving for single-aisle aircraft (short- and mid-range) is estimated at between 2 and 4% of total fuel consumption, depending on the specific operations of the airline.
“Moreover, having an independent electric motor driving the wheels will allow the aircraft to move backward and so to move autonomously from the gate (a tug will not be required anymore for pushback). This will save additional costs for the airline but also will save time for airlines and for airports as no connection/disconnection will be needed and engines can be started later in the taxiing process (1 to 3 min per rotation).”
Devillers also highlights the potential importance of the Chinese market for ETS. “China has amongst the longest average taxiing times [of any country] and so this system can bring the highest benefits. The country is also putting more and more energy into controlling its emissions of CO2 and other pollutants, and has shown a strong interest for this innovation.
“The MoU signed with CAEES will facilitate discussions with and access to the different players in the Chinese aviation industry. Being more familiar with Chinese airlines’ expectations, with Chinese airports’ specificities and with national regulatory constraints will help Safran Landing Systems to refine the system’s capabilities in order for us to offer a product that meets operational requirements in China,” Devillers reports.
Progress is also being made elsewhere. “The electric taxiing solution, which is the result of an extensive R&T [research and technology] phase led by Safran Landing Systems, has received ‘Authorisation To Market’ approval by Airbus for an application on the A320 Family,” Devillers says.
“Depending on airline feedback, the actual programme could subsequently be launched in the near future. This system will provide airlines with a sustainable solution which combines savings on operating costs (equal to several hundred thousand dollars per aircraft annually), independent movement on the ground and improvement of on-time departures with environmental advantages such as reduced carbon and NOx emissions, as well as less noise during taxiing.”