Naval Auxiliary Landing Field (NALF) San Clemente Island (ICAO: KNUC, FAA LID: NUC), also known as Frederick Sherman Field, is a military airport located on San Clemente Island, in Los Angeles County, California, United States. It has been owned by the United States Navy since 1937.

San Clemente Island is the southernmost Channel Island, covering 57 square miles (150 km2). The island is approximately 21 nautical miles (39 kilometres) long and is 4.5 nmi (8.3 km) across at its widest point. It lies 55 nmi (102 km) south of Long Beach and 68 nmi (126 km) west of San Diego.