Boeing, NASA, United Airlines Collaborate in SAF Research

DALLAS – Boeing has announced a collaboration with NASA and United Airlines (UA) to conduct in-flight tests to measure the impact of sustainable aviation fuel (SAF) on contrails and non-carbon emissions.

The second ecoDemonstrator Explorer by Boeing, which is a Boeing 737-10 plane designated for UA, is scheduled to undergo testing using both 100% SAF (Sustainable Aviation Fuel) and traditional jet fuel stored in separate tanks. NASA's DC-8 Airborne Science Lab will follow the commercial aircraft to evaluate the emissions and contrail ice particles generated by each type of fuel.

This comprehensive study, which will include the analysis of satellite imagery capturing contrail formation, aims to gain insights into how SAF affects the characteristics of contrails. Understanding these effects is crucial for determining the potential impact of contrails on atmospheric warming.

This initiative explores advanced fuels, engine combustor designs, and related technologies to mitigate atmospheric warming. World Energy supplies SAF from its Paramount, Calif., facility, with support from entities such as the U.S. Federal Aviation Administration (FAA), GE Aerospace, and the German Aerospace Center (DLR).

In air-to-air testing, NASA’s DC-8 Airborne Science Lab will fly behind the Boeing ecoDemonstrator Explorer to measure emissions and contrail ice particles. Image: NASA

Boeing's ecoDemonstrator Program

The partnership signifies the latest chapter in Boeing and NASA's ongoing effort to analyze SAF's role in emission reduction and environmental benefits. SAF, derived from sustainably produced feedstocks, offers remarkable potential by cutting emissions up to 85% over its life cycle, thereby presenting a significant avenue for reducing aviation CO2 emissions in the coming decades. Additionally, SAF produces less soot, leading to improved air quality in the airport vicinity.

Boeing's ecoDemonstrator program, now featuring specialized Explorer airplanes for short-term, focused projects, has made strides in advancing SAF research. Ground testing of SAF emissions took place on an Alaska Airlines (AS) Boeing 737-9 in 2021, followed by flight tests on ecoDemonstrator Boeing 777-200ER and 787-10 jets in 2022.

Boeing has committed to delivering commercial airplanes compatible with 100% SAF by 2030. The Boeing 737-10, belonging to Boeing's single-aisle 737 MAX family, reduces fuel use and emissions by 20% compared to its predecessors, emphasizing the company's dedication to sustainable aviation practices.

Boeing N772ET Boeing 777-200 (ecoDemonstrator Livery) — Boeing N772ET Boeing 777-200(ecoDemonstrator Livery) | Photo: Brad Tisdel/Airways

Comments from Test Partners

Boeing's Chief Sustainability Officer, Chris Raymond, expressed gratitude for the collaboration with NASA, United Airlines, and other valued partners, emphasizing the research's significance in enhancing the industry's understanding of the broader benefits of SAF beyond carbon emission reduction. Raymond believes that by continuing to take meaningful actions, the aerospace sector can achieve a more sustainable future together, building upon its track record of solving difficult challenges.

Rich Wahls, NASA mission integration manager for the Sustainable Flight National Partnership, highlighted the complexity and resource-intensive nature of flight testing, which he considers the gold standard for comprehending the impact of sustainable aerospace innovations on contrails and climate. NASA's decision to deploy the DC-8 aircraft for this collaboration reflects their recognition of the valuable flight data that will enhance predictive models.

United Airlines' Chief Sustainability Officer, Lauren Riley, expressed optimism about the collaboration's potential to deepen their understanding of contrails and the comprehensive benefits of transitioning to SAF, extending beyond greenhouse gas reductions.

GE Aerospace's Vice President of Engineering, Mohamed Ali, proudly supported the groundbreaking research collaboration, emphasizing its importance in advancing scientific understanding of SAF's impact on emissions for a more sustainable future of flight.

Markus Fischer, DLR Divisional Board Member for Aeronautics, stressed the need for close international cooperation to achieve climate-compatible aviation. The German Aerospace Center's extensive experience in researching the climate impact of the entire aviation system, including measurement technology and simulations, demonstrates their commitment to reducing both CO2 and non-CO2 effects.

Fischer emphasized that the continuation of transatlantic collaboration signifies the international dedication to mitigating aviation's climate impact.

Featured image: Boeing is partnering with NASA and United Airlines for in-flight testing to measure how sustainable aviation fuel (SAF) affects contrails and non-carbon emissions, in addition to reducing the fuel’s life cycle climate impact. Shown here, Boeing’s second ecoDemonstrator Explorer, a 737-10 destined for United Airlines with LEAP-1B engines, will fly with 100% SAF and conventional jet fuel in separate tanks and alternate fuels during testing. Image: Boeing