The team of aerospace specialists behind the ‘Emission and Climate Impact of Alternative Fuels’ (ECLIF3) study have reported “promising” early findings following a world-first study of the impact of 100 per cent sustainable aviation fuel on both engines of a commercial jet.
Airbus, Rolls-Royce, German research centre DLR and SAF producer Neste, carried out in-flight emissions tests and associated ground testing on an Airbus A350 aircraft powered by Rolls-Royce Trent XWB engines.
In-flight emissions tests and associated ground testing on the ECLIF3 programme began earlier this year and have recently resumed. The interdisciplinary team, which also includes researchers from the National Research Council of Canada and The University of Manchester, plan to publish the results in academic journals towards the end of next year and 2023.
Commenting on the study, Airbus’ new energy programme manager Steven Le Moing said: “Engines and fuel systems can be tested on the ground but the only way to gather the full set of emissions data necessary for this programme to be successful is to fly an aircraft in real conditions.
“In-flight testing of the A350 offers the advantage of characterising direct and indirect engine emissions, including particulates from behind an aircraft at high altitude.”
In April, the study flew three A350 flights over the Mediterranean Sea pursued by a DLR Falcon chaser plane to compare in-flight emissions of both kerosene and Neste’s hydro-processed esters and fatty acids (HEFA) sustainable fuel. The team also carried out compliance tests using 100 per cent SAF and no operational issues were experienced.
DLR’s divisional board member for aeronautics Markus Fischer added: “SAF has been shown to have a significantly lower carbon footprint over its life cycle compared to conventional jet fuel and now we are seeing it is advantageous in reducing non-CO2 effects too.
“Tests such as these are continuing to develop our understanding of 100 per cent SAF, its use in flight and we are seeing positive signs for its potential in climate mitigation. We look forward to studying the data from the second series of ECLIF3 flights, which restarted with a first chase flight above the Mediterranean earlier this month.”
