Emma D'Ambro, University of Washington, operating a CIMS instrument (chemical ionization mass spectrometer) aboard the NSF/NCAR C-130, as part of the Airborne Research Instrumentation Testing Opportunity (ARISTO) program. The purpose of the ARISTO program is to provide regular flight test opportunities for newly developed or highly modified instruments as part of their development effort. The inaugural ARISTO flight test program took place in September and October 2015 at EOL's Research Aviation Facility (RAF) located at Rocky Mountain Metropolitan Airport (RMMA) in Broomfield, CO.