Airplanes must fly at a lower speed to reduce the harmful emissions that are accelerating global warming, according to a new study that determined that reducing aircraft speeds by 15% could cut fuel consumption by 5%-7%.
Researchers at the University of Cambridge conducted the analysis, outlining sustainable targets for the aviation industry to lessen its environmental impact and take a significant step toward the ultimate goal: net-zero emissions by 2050. Right now, achieving this goal seems far off due to the current global emissions.
The study's authors found that aviation currently contributes around 4% to the rate of global warming, with 2.5% of that coming from carbon dioxide emissions alone. Their analysis established four realistic goals to meet by 2030, essential for making the 2050 net-zero target feasible. These include avoiding contrails, improving collaboration between governments and the aviation industry, developing sustainable aviation fuels, and adopting new technologies.
The researchers also proposed a "bold step" to reduce fuel burn by extending flight times through slower flying speeds. They suggest that reducing flight speed by about 15% could lower fuel consumption by 5%-7%. This change might require future aircraft designs to accommodate slower speeds. However, passengers would be affected, as longer flights could reduce airlines' efficiency and impact travelers willing to book even lengthier flights.
To offset longer flight times, the researchers recommend better airport and runway management, including shorter waiting times. While such changes would require system-wide adjustments, they could lead to up to a 50% reduction in fuel consumption by 2050.
Other "bold measures" proposed include building more advanced, fuel-efficient aircraft to replace older models and aligning flight ranges with different aircraft types. Professor Rob Miller, director of the Whittle Laboratory at the University of Cambridge, says these bold steps aren't being implemented yet because they require deep, global systemic change. "Airlines can't do this alone, nor can manufacturers or airports," Miller told The Times. "It’s not that no one wants to make these changes, it’s just that the system’s complexity makes it incredibly difficult."
Professor Miller, an expert in aerothermal technology, says the aviation industry is at a critical crossroads, similar to the automotive industry in the late 2000s. "Back then, discussions centered around biofuel as an alternative to gasoline and diesel—until Tesla revolutionized the market with electric vehicles. Our five-year plan is designed to speed up aviation’s transition toward net-zero emissions by 2050."