Aircraft Particle Inlets: State-of-the-Art and Future Needs

Abstract

Aircraft inlets connect airborne instruments for particle microphysical and chemical measurements with the ambient atmosphere. These inlets may bias the measurements due to their potential to enhance or remove certain particle size fractions in the sample. The aircraft body itself may disturb the ambient air streamlines and, hence, the particle sampling. Also, anisokinetic sampling and transmission losses within the sampling lines may cause the sampled aerosol to differ from the ambient aerosol. In addition, inlets may change the particle composition and size through the evaporation of water and other volatile materials due to compressibility effects or heat transfer. These problems have been discussed at an international workshop that was held at the Leibniz-Institute for Tropospheric Research (IfT) in Leipzig, Germany, on 12?13 April 2002. The discussions, conclusions, and recommendations from this workshop are summarized here.