Measurement and analysis of aircraft engine PM emissions downwind of an active runway at the Oakland International Airport

The growth of commercial aviation has fueled concerns over air quality around airports and the surrounding communities. Airports must expand their operations to meet the increase in air traffic, but expansion plans have been delayed or canceled due to concerns over local air quality. This paper presents the methodology for real-time measurements of aircraft engine specific Particulate Matter (PM) emissions and analysis of the associated high resolution data acquired during normal Landing and Take-Off (LTO) operations 100-300 m downwind of an active taxi-/runway at the Oakland International Airport. The airframe-engine combinations studied included B737-300 with CFM56-3B engines, B737-700/800 with CFM56-7B engines, A320 with V2500-A5 engines, MD-80 with JT-8D engines, A300 with CF6-80 engines, DC-10 with CF6-50 engines, and CRJ-100/200 with CF34-3B engines. For all engine types studied, the size distributions were typically bimodal in nature with a nucleation mode comprised of freshly nucleated PM and an accumulation mode comprised mostly of PM soot with some condensed volatile material. The PM number-based emission index observed ranged between 7 × 1015-3 × 1017 particles kg−1 fuel burned at idle/taxi and between 4 × 1015-2 × 1017 particles kg−1 fuel burned at take-off, and the associated PM mass-based emission index (EIm) ranged between 0.1 and 0.7 g kg−1 fuel burned at both the idle/taxi and take-off conditions. Older technology engines such as the CFM56-3B and JT8D engines were observed to have as much as 3× higher PM EIm values at take-off compared to newer engine technology such as the CFM56-7B engine. The results from this study provide information for better characterizing evolving PM emissions from in-service commercial aircraft under normal LTO operations and assessing their impact on local and regional air quality and health related impacts.

► Real-time measurements of aircraft engine specific Particulate Matter emissions. ► At idle, number-based emission index was 7 × 1015-3 × 1017 particles kg−1 fuel burned. ► At takeoff, number-based emission index was 4 × 1015-2 × 1017 particles kg−1 fuel burned. ► Mass-based emission index was between 0.1 and 0.7 g kg−1 fuel burned at idle and takeoff. ► Mass-based emissions for older technology engines were 3× higher at takeoff.