Development and present configuration of the NASA GSFC/WFF helicopter-based remote sensing system

There is a need for calibrated remote sensing data from airborne platforms emphasizing the spatial, spectral, temporal, bidirectional and polarization information domains. A system developed by NASA Goddard Space Flight Center and Wallops Flight Facility utilizing a helicopter as the platform has proven to be a versatile means of acquiring such data. As the system evolved, it was used for the acquisition of data supporting field measurement campaigns such as an acid deposition effects study, the First International Satellite Land Surface Climatology Project (ISLSCP) Field Experiment (FIFE), the Forest Ecosystems Dynamics Project (FED), and the BOReal Ecosystem Atmosphere Study (BOREAS) among others. The data collected with the helicopter system have been used to develop relationships between vegetative parameters and remotely sensed measurements, validate atmosphere and vegetation models, address scaling issues, and provide low altitude data for instrument calibration studies. Off-the-shelf field and experimental instrumentation have been flown as part of the system. Most recently, gyro-stabilized, pointable mounts and an automatic sun-tracking sun photometer were specifically designed and fabricated for the system. The stages of development of the helicopter system over a twelve year period are described and illustrate the advantages and limitations afforded to investigators using helicopter-based systems