AEROSOLS WITH AN IN-SITU, MULTI-WAVELENGTH MULTICHANNEL NEPHELOMETER

CHARACTERIZING THE OPTICAL PROPERTIES OF INDIVIDUAL AEROSOL PARTICLES IN THE AEROSPACE ENVIRONMENT REQUIRED TO ALLOW PERFORMANCE ANALYSIS OF OPTICAL AND INFRARED SYSTEMS AND OPTICAL OBSCURATION COUNTERMEASURES. THERE EXISTS A NEED TO DEVELOP NEW INSTRUMENTATION WHICH CAN AUTOMATICALLY AND REMOTELY (IN-SITU) MEASURE AND RECORD THE TOTAL SCATTERING PATTERN FROM INDIVIDUAL AIRBORNE PARTICLES OF DIFFERENT MATERIAL AND SHAPES UNDER VARIOUS NATURAL AND MAN-MADE ATMOSPHERIC CONDITIONS. KNOWLEDGE OF PHYSICAL/OPTICAL PROPERTIES OF ATMOSPHERIC ATMOSPHERIC AEROSOLS WILL GREATLY ENHANCE THE CAPABILITY OF MODELING ATMOSPHERIC TRANSMISSION AND PREDICTING PERFORMANCE OF OPTICAL AND INFRAFED SYSTEMS. THE OBJECTIVE OF THE PHASE I EFFORTS ARE TO IDENTIFY THE SYSTEM REQUIREMENTS, INVESTIGATE THE TECHNICAL FEASI BILITY OF THE DEVELOPED CONCEPT AND DESIGN A PROTOTYPE SYSTEM INCLUDING A PARTICLE (INLET) SAMPLING SYSTEM FOR POTENTIAL AIRCRAFT USAGE, IDENTIFY LIGHT SOURCE, OPTICS AND DETECTORS FOR THE SYSTEM, AND A DATA ACQUISITION SYSTEM. THE PROPOSED APPROCH IS TO MEASURE THE SPECTRAL AND ANGULAR VARIATION OF SCATTERED LIGHT PATTERNS OF INDIVIDUAL PARTICLES OVER 4 STERADIANS BY EMPLOYING MULTIPLE SOURCES AND DETECTORS AND A FAST RESPONSE DATA ACQUISITION SYSTEM. PHASE I RESULTS ARE INTENDED TO PROVIDE DETAILS OF SYSTEM DESIGN, HARDWARE IDENTIFICATION AND THEORETICAL ANALYSIS THAT WILL DIRECT THE IMPLEMENTATION OF PHASE II - THE ACTUAL CONSTRUCTION OF THE SYSTEM.