Powerfully running on SAF

The successful first flight test of the A400M and its TP400 engines with Sustainable Aviation Fuel was performed in Spain.

Nov 2022

In July, an Airbus A400M performed a test flight with one of its TP400 engines powered by 29% Sustainable Aviation Fuel (SAF). This milestone is a sign that also military programs have also entered the race for the aviation decarbonization.

The test took place in July in Seville (Spain) with an A400M "Grizzly 4" which made a flight of over an hour with one of its TP400* turboprops powered by a mixture comprising 29% SAF*.

“For this first flight, we are using a type of SAF called HEFA (Hydroprocessed Esters and Fatty Acids) which is made of residuals of oils, vegetables and fats, and also free of aromatics and Sulphur, so it is very efficient and good for the engines”, explained Ana Belén Blanco, Technical Leader for SAF in A400M. “It is a drop-in fuel, so there is no need to modify the engines´ systems and there are no technical limitations”, she said.

“During the flight, we performed a close comparison between engine number 2, the one using SAF, and the other 3 engines using standard fuel Jet A1, so we had a very good opportunity to compare the performance of the different fuels”, said César González, Flight Test Engineer at Airbus Defence and Space. “The results we got confirmed that using this blended SAF does not affect engines or aircraft performance, so the A400M can receive the whole potential of it in terms of environmental benefit”, González added.

The A400M fueled with SAF in Sevilla before the take off. © 2022 Airbus

Engine and flight data analyzes determined that the TP400 engines were compatible with a mixture containing up to 50% SAF. Recently, A400M operators expressed interest in using 50% certified SAF. This test is a first step is a first step in the roadmap for increased use of SAF on the military products.

“This flight is a significant step forward, and relying on the expertise of our parent companies, we are confident that TP400-D6 robust design will enable us to reach the highest SAF standards”, said Stephan Schlisske, Head of Design Organisation of Europrop International.

Sustainable Aviation Fuels: a major lever for decarbonization

The introduction of biofuels is one of the priority levers in the roadmap for Safran and the players in the aeronautics industry to achieve its decarbonization objectives. In this context, Safran Aircraft Engines is participating in several projects aimed at using these sustainable fuels in larger quantities and certifying their use on the LEAP in particular. Let us quote for example the integration of 10% of biofuels in engine tests at the Villaroche plant (a figure which will rise to 35% by 2025), or the VOLCAN project which last November enabled the first flight of an A319neo powered by LEAP engines operating on 100% sustainable fuel.

The TP400 Power Gearboxes are designed, produced and serviced by Avio Aero, here a view of their assembly at the Rivalta di Torino plant.

*The A400M is powered by four 11,600 horsepower TP400 turboprop engines, the most powerful in the Western world. They are designed by the Europrop International GmbH (EPI) consortium bringing together 4 European engine manufacturers, the British Rolls-Royce, the Spanish Industria de Turbo Propulsores (ITP), the German MTU Aero Engines and the French Safran Aircraft Engines, main partner with 32% program share. TP400 power gearboxes are designed, manufactured and serviced by Avio Aero.

** Hydroprocessed Esters and Fatty Acids / Hydro-treated esters and fatty acids.

The original version of this story is by Airbus and Safran. Cover image is courtesy of Safran, © Adrien Daste