The Common-Path Interferometric Particle Sizer (CPIPS): A new open-path airborne instrument for characterizing small ice and aerosol

Contrails represent the single largest impact of aviation emissions on the environment, responsible fornbsp;over half the estimated radiative forcing. Improved understanding of contrail formation processes and the influence of aero-engine emissions is critical to the development of next-generation aero-engines and fuels able to mitigate the warming effects of contrails.nbsp;Our project will address gaps in the current state-of-the-art measurement capabilities and enable measurements of small ice crystals and aerosols in the initial phases of contrail formation. This will be accomplished through the development of an open-path airborne instrument, capable of measuring the size, refractive index, and asphericity of particlesnbsp;between 100-900 nm in diameter through the use of self-reference interferometry. This instrument would represent the first major advance in airborne wing-mounted aerosol instrumentation in over 40 years. In Phase I, we propose the development and testing of a simplified breadboard optical system to validate our approach. Various particle types with known size, refractive index and/or shape will be tested in the prototype to evaluate its performance. In Phase II, additional testing will be carried out, and a final PMS canister design will be developed and built.