In 2021, a United Airlines test flight using 100% sustainable aviation fuel took off from Houston, emphasizing the industry's push towards environmentally friendly flying. The U.S. government's 'Grand Challenge' aims to meet 100% of jet travel demand with sustainable fuels by 2050, sparking a wave of investments and technological advancements in the aviation sector. Southwest Research Institute's Hsiang Yee Hoekstra explains the journey towards making sustainable aviation fuel economical at scale. The article delves into three main pathways for greener fuel: fuel cells, power-to-liquids technology, and biofuel. Companies like American Airlines are exploring hydrogen fuel cell engines, while investments in power-to-liquids technology are on the rise, potentially offering a sustainable solution through synthetic eFuel production. Biofuel, derived from various biomaterial sources, is currently a viable option for blending with traditional jet fuel, although cost remains a hurdle. While advancements in green aviation technologies are promising, challenges such as cost-effectiveness and scalability still need to be addressed. The industry is driving towards decarbonizing aviation, with a focus on innovation and sustainable practices to achieve the goal of greener skies in the future.