Last July, the A400M program team, together with the Military Air Systems unit of the Defense and Space division (Airbus Defense and Space), launched the Sustainable Aviation Fuel (SAF) test flight campaign. The first test flight with 29% SAF on one of the 4 engines proved successful, furthering the decarbonization of military flights.
As the European aerospace manufacturer reports, a mixture of nervousness and emotion washed over team members on the runway of the Airbus plant in Seville, Spain, on an extremely hot July day when the first test flight with SAF was made. executed. finally happens with an Airbus A400M.
MSN4 (aircraft production serial number), registration EC-404, or ‘Grizzly 4’ as it is known to the team, entered the runway with one of its engines, specifically engine number 2, powered by a fuel mixture containing 29% SAF.
“For this first flight we are using a type of SAF called HEFA (Hydroprocessed Esters and Fatty Acids) which is made from waste oils, vegetables and fats, and also free from aromatics and sulphur, so it is very efficient and good for engines.. It is a drop-in fuel, which means that there is no need to modify engine systems and there are no technical limitations.”, explains Ana Belén Blanco, SAF technical leader on the A400M.
For this first test flight, the use of the SAF was limited to one engine in order to better analyze the behavior of the fuel system that powers a single engine.
The test flight headed north to Huelva and then landed safely in Seville, totaling more than an hour’s journey. The crew’s satisfaction was already on their faces as they disembarked, ready to share the result.
“During the flight, we made a rough comparison between engine number 2, which was using SAF, and the other 3 engines using standard Jet A1 fuel, so we had a great opportunity to compare the performance of the different fuels.said César González, flight test engineer at Airbus Defense and Space.
“The results we obtained confirmed that the use of this mixed SAF does not affect the performance of the engines or the aircraft, allowing the A400M to realize its full potential in terms of environmental benefit.Gonzalez added.
SAF is a proven alternative fuel that can reduce CO₂ emissions over the life cycle by up to 85% compared to conventional fuel. The maiden flight of an A400M with SAF showed that both the aircraft and the previously untested TP400-D6 engines meet these new requirements with a 50% blend SAF certified for more sustainable military aviation.
Airbus and EuroProp International, responsible for the design, development, manufacture and support of the TP400-D6 turboprop engine, have agreed to establish the joint roadmap for 100% SAF certification, making this first flight a step towards of that purpose.
With more than 100 A400M aircraft deployed in 8 different countries, Airbus notes that offering the ability to use SAF is one of the company’s priorities. “Our operators have expressed their willingness to use SAF in their military operations and we are here to meet your needs.”, says Rocío Gutierrez Alonso, chief engineer of the A400M plant.
‘Grizzly 4’: A Seasoned Warrior for a Crucial Mission
Such an important mission required one of Airbus’ most experienced ‘warriors’. The ‘Grizzly 4’, in service since December 20, 2010, was selected from the “troops” to conduct this first test flight with SAF under Airbus Military Air Systems. And this is how MSN4 sees itself leading its successors into the future: the decarbonisation of military aviation.
MSN4 has been used for all kinds of tests over the years. Among other things, it played an important role in the development and certification of in-flight refueling (AAR) capabilities such as refueling and receiving, in addition to launching cargo and parachutes.
This first flight with SAF is number F994 in MSN4’s impeccable track record, so it’s just six flights for a well-deserved “retirement” after nearly 2,000 hours of flying time.
The Grizzly 4′ shows its wear and tear from all operations, but its sturdiness, capacity and reliability have remained intact throughout its career. The manufacturer emphasizes that the aircraft is still in good condition to fulfill one of its last and crucial missions: leading the way towards more sustainable military aviation at Airbus.
The race for sustainable military aviation
This maiden flight, powered by a mixed-SAF engine, is a first step in Airbus’ long-term roadmap to achieve 100% SAF readiness and certification for the A400M.
Operators of the Airbus A400M have recently expressed an interest in using 50% certified SAF, so Airbus’ goal was to conduct this first test flight as part of its best practices. Following the successful performance, four-engine operators can now fly with up to 50% certified mixed fuel, and Airbus will continue to support them in doing so.
In addition, Airbus, OCCAR and A400M Nations are involved in the initial discussions to develop the roadmap for the certification and operational use of 100% SAF in aircraft. In this SAF project, all Airbus divisions work closely together to share knowledge and lessons learned.
“This flight of an A400M with SAF is a first step in our division creating the momentum to move steadily and at an efficient pace on this path to sustainability.Gutierrez said.
Going forward, more SAF flight tests are planned in the coming months for the C295 and A330 MRTT, which will soon join the A400M in this race for sustainable military aviation.