The data in the Sunphotometer Optical Thickness Data from C130 Aircraft data set were collected in June, July and August 1987, and in August 1989. The data was collected at selected locations within the FIFE study area. Atmospheric optical depths derived from measurements of solar radiation by the airborne suntracking sunphotometer are available in this data set. These data are necessary for atmospheric correction of data from Earth viewing airborne and satellite sensors in the visible and near infrared regions of the electromagnetic spectrum. The data show that atmospheric optical depth changes significantly both spatially and temporally. Variability in atmospheric optical properties and substantial differences in atmospheric optical properties during the data collection, emphasize the need to make quantitative measurements of atmospheric optical properties at the time of remote sensing data acquisition.