Airbus A400M first test flight with SAF – one step forward to a more sustainable military aviation

The Sustainable Aviation Fuel (SAF) test flight campaign has been launched by the Airbus A400M programme team with the Military Air Systems unit of the Defence and Space division this summer. In military aviation, Airbus advances its commitment to cleaner skies after a first test flight with a load of 29% SAF in one of its engines was successful.

Airbus A400M first test flight with SAF – one step forward to a more sustainable military aviation

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. It is a drop-in fuel, so there is no need to modify the engines´ systems and there are no technical limitations

explained Ana Belén Blanco, Technical Leader for SAF in A400M

Over the years, MSN4 has been used for a variety of testing. It was important for, among other things, the development and certification of AAR capabilities as a tanker and receiver as well as for cargo and parachute drops since it was made such that the cargo hold was instrumentation-free and completely usable for aerial delivery or additional fuel tanks (CHT). After approximately 2,000 flight hours and this first flight with SAF, the MSN4 will “retire” after only six more flights, which is a well-deserved milestone.

One of the MSN4’s engines, especially engine number 2, hit the runway with a combined load of 29% SAF, or “Grizzly 4,” as the aircraft is known among the team.

To better understand the behaviour of the fuel system feeding a single engine, SAF’s use for this first test flight was restricted to one engine.

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. 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

said César González, Flight Test Engineer at Airbus Defence and Space

The aeroplane, which departed from the San Pablo plant runway in Seville and travelled for more than an hour before safely landing back in Seville, took off for the North of Huelva.

A400M Flight Test

SAF is a tried-and-true alternative fuel that, when compared to conventional fuel, can cut life cycle CO2 emissions by up to 85%. This first SAF-powered A400M flight proved that the aircraft and its TP400-D6 engines, which had never been tested with SAF before, comply with the new fuel specifications with a blend of 50% certified SAF for a more environmentally friendly military aviation.

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

This first flight represents a step toward the 100% SAF certification that Airbus and EuroProp International, which is in charge of the TP400-D6 turboprop’s engine design, development, production, and support, have agreed to establish jointly.

This first flight of an A400M using SAF is a first step in our division that creates the momentum to progress steadily and persistently at an efficient pace along this path towards sustainability. In order to move forward, more flight tests with SAF are planned for the coming months for the C295 and the A330 MRTT, which will soon join the A400M in this fascinating race towards sustainable military aviation

said Rocío Gutierrez Alonso, Chief Engineer of A400M Power Plant

Furthermore, preliminary conversations are being held between Airbus, OCCAR, and the A400M Nations to create a path for the certification and operational use of 100% SAF in aircraft.