Impact of efficiency-driven aircraft technology improvements on climate and air quality

Abstract

The impacts of commercial aviation on global climate and air quality have led to an industry-wide movement to reduce its environmental impact. While technological developments in aircraft propulsion, materials, and aerodynamics aim to reduce fuel consumption and CO₂ emissions, these efforts often overlook the full climate and air quality impacts of aviation, especially emissions impacts of NOₓ, CO, HC, soot, and contrails. This study assesses the environmental constraints associated with advancements driven by fuel efficiency by modeling aircraft technologies across narrow-body, wide-body, and regional jet categories. By focusing on near-future technology insertions in materials, aerodynamics, and propulsion, we can compute quantifiable environmental metrics such as temperature changes, global warming potentials, and monetized environmental damages. Our modeling shows that certain propulsion technologies — such as increased component polytropic efficiencies or higher allowable turbine-metal temperatures — can reduce fuel consumption by more than 10% under favorable re-optimizations of engine design. However, they often raise engine core pressures or temperatures in ways that increase NOₓ emissions indices by more than 30%. This can lead to worse air quality damages, offsetting some of the CO₂ savings and in some cases result in a 2% increase in environmental damages on a total net present value (NPV) basis. Primary structure material upgrades consistently reduce both fuel burn and NOₓ emissions. These improvements in air quality from reduced NOₓ result in a 10% reduction of the total NPV from environmental impacts. This analysis shows that focusing on fuel efficiency alone can be an incomplete metric towards understanding the environmental impact of an aircraft. By offering a quantitative assessment of how near-future upgrades can affect both climate and air quality, this study also provides guidance on which technology paths are most effective in reducing the overall environmental impact of aviation.