The LARGE group operates a suite of probes to measure in-situ cloud microphysical properties. Probes are typically mounted at an under-wing or wing-tip position in unperturbed air. The package of probes can be tailored to specific science objectives or mounting-point availability considerations. The following probes are available:

CAPS (Cloud, Aerosol, Precipitation Spectrometer), Droplet Measurement Technologies.  The CAPS contains individual sensors.  The CAS (Cloud Aerosol Spectrometer) measures size distributions of clouds and aerosols between 0.5-50µm diameter using forward-scattered light intensity from a 658nm laser. Response is calibrated with glass beads. The CIP (Cloud Imaging Spectrometer) measures size distributions of droplet and precipitation particles between 15-150µm diameter recording shadows on an optical array. The CIP is calibrated using a spinning disk. A hotwire is also used to measure total liquid-water-content. Each probe utilizes a local measurment of airspeed, temperature, and static pressure for quantification and has de-icing capability.
CDP (Cloud Droplet Probe), Droplet Measurement Technologies. The CDP measures droplet and aerosol size distributions between 2-50µm diameter using forward-scattering from a 658nm laser.  The probe is calibrated with glass beads and has de-icing capability.
WCM-2000 (Science Engineering Associates).  Measures Liquid Water Content (LWC) using two independent hotwire elements, Total Water Content (TWC) using a scoop sensor, and an element oriented parallel with the airstream as a control to establish the background response at that specific airspeed, temperature, and pressure.  Ice Water Content (IWC) is calculated as the difference between TWC and LWC. Each element operates by maintaining a constant temperature, and the current necessary to maintain that temperature is related directly with water content.  
 

The NASA GSFC Compact Airborne NO2 Experiment (CANOE) instrument measures nitrogen dioxide (NO2) on both pressurized and unpressurized (high-altitude) aircraft. Using non-resonant laser induced fluorescence (LIF), CANOE possesses the high sensitivity, fast time response, and dynamic range needed to observe NO2 throughout the troposphere and lower stratosphere.

The NASA Rapid OZone Experiment (ROZE) is an in situ instrument capable of measuring ozone (O3) throughout the troposphere and lower stratosphere on airborne platforms. The instrument uses cavity-enhanced absorption to measure the amount of ozone in a sampled volume flowing through an optical cell. The high-sensitivity of the cavity-enhanced detection scheme and the small sample volume enable high precision measurements in short integration times, making this instrument suitable for measuring O₃ fluxes (the exchange between the Earth's surface and atmosphere) with the eddy covariance technique. The instrument is designed for autonomous operation and requires minimal support (and no gases or dry ice) in the field. An inlet mounted in the free stream is needed to sample ambient air.