Radar detection of surface oil slicks

The United States Coast Guard currently is developing AIREYE, an all-weather, day/night airborne surveillance system, for installation aboard future medium range surveillance (MRS) aircraft. As part of this program, a series of controlled tests was conducted off southern California during May, 1976 in order to evaluate the oil slick and surface target detection capabilities of two Motorola-developed side-looking radars. The systems, a real-aperture AN/APS-94D and a synthetic-aperture coherent-on-receive (COR), were flown over the Santa Barbara Channel on May 19, 1976. Targets imaged during the coincident overflights included natural oil seepage, simulated oil spills, oil production platforms, piers, mooring buoys, commercial boats and barges, small pleasure craft, and coastal kelp beds. This paper describes the test program and compares oil and surface target detection results for the two systems. Based on an analysis of imagery from the coincident radar runs, COR provided better detection of natural and man-made oil slicks, whereas the AN/APS-94D consistently exhibited higher surface target detection results.