The National Underwater Reconnaissance Office (NURO) is the "hidden younger brother"[further explanation needed][citation needed] of the National Reconnaissance Office (NRO). NRO was initiated in 1960 and developed as a common office for United States Air Force and the Central Intelligence Agency (CIA) to manage satellite reconnaissance. The first revelation about NRO came in 1973, but its very existence was not declassified until 1992. According to Jeffrey T. Richelson, "[m]ost often the Under Secretary of the Air Force served as a Director of the NRO".[1] NURO was initiated in 1969 and developed as a common office or liaison office for the United States Navy and the CIA to manage underwater reconnaissance. NURO used "special project submarines" like USS Seawolf (SSN-575), USS Halibut (SSN-587), and USS Parche (SSN-683) deep inside the waters of the Soviet Union to put out listening devices, tap communication cables, monitor Soviet Navy bases and record sound signatures of Soviet submarines. NURO is a little-known agency; even its name has been secret and its very existence was first revealed in 1998. The United States Secretary of the Navy has served as its director.[2]