Aircraft Particle Emissions Experiment Series

NASA has been studying various types of emissions from commercial aircraft to develop ways to reduce emissions and protect the environment. In recent years, fine particle emissions from aircraft have been identified as possible contributors to global climate changes and to lowering local air quality. These emissions are produced when a hydrocarbon fuel (such as modern jet fuel, which is primarily kerosene) does not burn completely. Incomplete combustion often occurs at the lower power settings used for aircraft descent, idling and taxiing. This produces fine carbon particles, or soot, as well as particles of nonvolatile organic compounds. The LARGE group studied emissions from the NASA-DC (CFM56 engines) in a series of three-APEX tests:

• APEX-1: April 2004 in Palmdale, Calif.
• JETS-APEX2: August 2005 at Oakland International Airport
• APEX-3: November 2005 at Cleveland Hopkins International Airport

Experimenters preparing to sample the exhaust of the NASA DC-8 engines.	  

Hydrocarbon speciation change as power increases with more alkenes and aromatics produced at take-off power settings.	  

Related Publications:

Wey et al, Journal of Propulsion and Power 07 - studying emissions from the NASA DC-8 (CFM56 engines), http://arc.aiaa.org/doi/abs/10.2514/1.26406

Herndon et al, Environmental Science & Technology '09 - the speciation of gas-phase hydrocarbon emissions are relatively independent of the engine type, http://pubs.acs.org/doi/abs/10.1021/es801307m

Beyersdorf et al, Atmospheric Environment '12 - the gas-phase hydrocarbon emissions are dependent on the aircraft power conditions, http://www.sciencedirect.com/science/article/pii/S1352231012006991