Based on the first results of a global study on the efficiency of sustainable aviation fuel -SAF- in the two engines of a commercial aircraft, the results are encouraging, according to the European manufacturer.
Through a statement, Airbus reported that “the ECLIF3 study, involving Airbus, Rolls-Royce, German aerospace research center DLR and SAF manufacturer Neste, is the first to measure 100% SAF simultaneously on both engines of a commercial airliner.” The aircraft chosen for the tests was the Airbus A350 FlightLab, powered by Rolls-Royce Trent XWB engines.
Also involved in the work are teams of researchers from the National Research Council of Canada and the University of Manchester in the United Kingdom. Final results, which they expect to have defined between late 2022 and early 2023, will serve to deepen Airbus’ and Rolls-Royce’s efforts to ensure that the industry is ready for large-scale use of UAS.
Currently, aircraft are only able to operate on 50% sustainable aviation fuel, so the two companies are working together to certify 100% operability. Another important issue is that, at the moment, the production of PBS is very limited in comparison to the large demand that would exist if it were approved for use.
In April this year, the A350 performed three test flights over the Mediterranean Sea using sustainable aviation fuel produced by Neste. A DLR Falcon escorted the flights, the objective of which was to measure emissions during each operation to compare the results between those performed with conventional fossil fuels and those operated with SAF.
Furthermore, the monitoring team conducted compliance tests on operations using Neste’s hydro processed esters and fatty acids (HEFA) sustainable fuel and reported that no operational problems were experienced.
“In-flight emissions testing resumed this month with 100% SAF and a HEFA/Jet A-1 fuel blend, and ground emissions tests were also conducted to quantify the benefits of SAF on local air quality. The research team found that SAF releases fewer particulates than compared to conventional kerosene at all engine operating conditions tested, which points to the potential to reduce climate impact and improve air quality around airports,” the release reads.
One very important issue being analyzed by the Airbus-led team has to do with the relationship between density and energy content of PBS. They reported that, compared to conventional fuel, sustainable fuel is less dense and has a higher energy content, so it could increase efficiency by requiring less of it – and therefore less weight – for the same flight.
Steven Le Moing, Airbus New Energy program manager, stressed the need for in-flight testing to gather the full set of emissions data. At the same time, he added that “A350 testing offers the advantage of characterizing direct and indirect engine emissions, including particulates from the rear of an aircraft at high altitude”.
For his part, Simon Burr, Rolls-Royce’s Director of Product and Technology Development for Civil Aerospace, said, “This research adds to the tests we have already conducted on our engines, both on the ground and in the air, which have found no engineering obstacles to our engines running at 100% SAF. If we are to truly decarbonize long-haul air travel, 100% SAF is a critical element and we are committed to supporting its certification for service”.
As we have already mentioned, SAF is one of the main commitments to reduce the environmental impact of the industry in the short term, given that its 100% utilization seems to be feasible, as this study is demonstrating. Undoubtedly, the fact that two major companies in the sector such as Airbus and Rolls-Royce are working to demonstrate their safety and achieve certification is very promising.
While not offering emission-free flights, the use of sustainable aviation fuels can reduce the emission of carbon dioxide into the environment by up to 80%. “SAF has been shown to have a significantly lower carbon footprint over its life cycle compared to conventional jet fuel, and we are now seeing that it is also advantageous in reducing non-CO2 effects”, said Markus Fischer, DLR Aeronautics Division Council member.
“Tests such as these continue to develop our insight into the use of 100% SAF in flight and we are seeing positive signs of its potential in mitigating the impact on the environment. We look forward to studying the data from the second series of ECLIF3 flights, which resumed with a first chase operation over the Mediterranean earlier this month”, he concluded.
