Project Artemis was a United States Navy acoustics research and development experiment from the late 1950s into the mid 1960s to test a potential low-frequency active sonar system for ocean surveillance. The at sea testing began in 1960 after research and development in the late 1950s. The project's test requirement was to prove detection of a submerged submarine at . The experiment, covering a number of years, involved a large active element and a massive receiver array.
The receiving array was a field of modules forming a three dimensional array laid from 1961 to 1963 on the slopes of a seamount, the Plantagenet Bank (), off Bermuda. The modules, attached to ten lines of cable, were masts with floats on top to keep them upright. Each module mounted sets of hydrophones. The receiving array terminated at Argus Island, built on the seamount's top, with data processed at the laboratory that was also constructed for the project. The laboratory was then the Bermuda Research Detachment of the Navy Underwater Sound Laboratory.
The active source array was to be suspended at to from the former tanker . The 1440-element active array had a one megawatt acoustic output (180 dB) with a center frequency of 400 Hz.
Though Artemis failed the final test and resulted in no operational system, it set the agenda for research in ocean acoustics and engineering such systems for the future.
Background
World War II experience prompted the U.S. Navy to examine the threat of Soviet submarines which had been improved by captured German technology. As a result of the threat being considered high risk sonic detection became a top priority. The Navy approached the National Science Foundation's Committee for Undersea Warfare for advice. Following the recommendations the Navy established a study under Massachusetts Institute of Technology auspices designated Project Hartwell which in 1950 recommended development of a long range passive acoustic detection system. By 13 November 1950 a letter contract had been issued to Western Electric to develop the bottom array system exploiting low frequencies. A test array was laid in the Bahamas off Eleuthera and upon successful tests with a U.S. submarine an order for six such systems was issued in 1952. The Sound Surveillance System (SOSUS), its name and purpose classified, was given the unclassified name Project Caesar to cover its development and maintenance. In 1956, as the last of the Atlantic SOSUS systems were being installed, Chief of Naval Operations Admiral Arleigh Burke convened a summer study similar to the Hartwell study designated the Nobska Study coordinated by the Committee on Undersea Warfare. Admiral Burke was particularly concerned with the threat of Soviet nuclear submarines in light of the capabilities of the nuclear submarine had been demonstrated.
Much of the study focused on undersea warfare and the need for nuclear anti-submarine submarines but also, in looking at SOSUS, recommended research and development of potential long range, active sonar systems. It also focused on the need to understand the ocean environment. A particular area of investigation was whether an active system could be developed with the power and directivity to exploit ocean zones the passive system being installed might not. With respect to the Navy active sonar project designated Artemis, to run from 1958 to 1963, an understanding of the ocean environment was vital. If the project was to succeed the full efforts of every ocean scientist, technician and laboratory on the Atlantic coast was likely required yet there were only six to seven hundred such people that were qualified. The need to meet that requirement and long term antisubmarine needs of the Navy drove large increases in academic and research budgets for oceanography.
As Project Artemis was undergoing tests in the early 1960s SOSUS tracked the first U.S. ballistic missile submarine across the Atlantic in 1961. In June 1962 SOSUS made the first detection and classification of a Soviet diesel submarine, and during the Cuban Missile Crisis in October tracked Soviet Foxtrot-class submarine with correlated sighting by aircraft. On 6 July 1962 the SOSUS array terminating at Barbados demonstrated detection range by identifying a Soviet nuclear submarine transiting off Norway.