Sustainable Aviation Fuel (SAF) has been identified as one of the key elements in helping achieve the aviation industry’s ambitious emissions reduction goals. Many big aero engine manufacturers in the world have already successfully tested SAF, and several pioneering flights have confirmed the efficiency of this alternative fuel.
Recently, Emirates operated its first milestone demonstration flight on a Boeing 777-300ER, powering one of its engines with 100% SAF. The Boeing 777-300ER took off from Dubai International Airport (DXB), then flew for more than an hour over the Dubai coastline before returning to the airport.
The SAF-powered demonstration flight holds particular significance as the UAE declares 2023 the ‘Year of Sustainability.’ The year will showcase the Arabian Peninsula nation’s commitment to seeking innovative solutions to challenges such as energy, climate change, and other sustainability-related issues. The flight supports the industry’s collective efforts to enable a future of 100% SAF flying and help advance the country’s sustainability goal.
Emirates’ demonstration flight was the first flight of this kind in the Middle East and North Africa, and it was the first Boeing 777 to fly with 100% SAF in a GE engine. It supports broader efforts to reduce lifecycle CO2 emissions as the industry looks to increase the use of sustainable fuel.
The flights will also help refine the manual for future fuel demonstrations and support future certification where 100% drop-in SAF is approved for aircraft. Currently, SAF is approved for use on all aircraft but only in blends of up to 50% with conventional aviation fuel.
Emirates worked alongside partners GE Aerospace, Boeing, Honeywell, Neste, and Virent to acquire and develop a SAF blend that mimics the properties of conventional jet fuel. At each mixing ratio, a series of measurements of the physical and chemical properties of the fuel were performed.
After multiple lab tests and rigorous trials, they arrived at a perfect blending ratio that was almost identical to conventional jet fuel. Eighteen tonnes of SAF were blended, comprised of HEFA-SPK provided by Neste and HDO-SAK from Virent. The 100% SAF supplied one GE90 engine, with conventional jet fuel supplying the other engine of the Boeing 777.
The test flight further demonstrated the suitability of the specially blended SAF as a safe and reliable fuel source. The promising outcome of this initiative also increases the industry database, and research on SAF blends to greater proportions, paving the way for standardization and future approval of 100% drop-in SAF as a replacement for jet fuel, well above the current 50% blend limit.