A massive order was made by the Iranian government in an attempt to modernize the Iranian Imperial Navy and give it capability to patrol the Caspian Sea, Persian Gulf and Indian Ocean. The Iranian Navy had placed an order for 4 s equipped with Standard missiles, Harpoon missiles, Phalanx CIWSs and Mark 46 torpedoes, 3 used retrofitted s (these were transferred rather than sold to Iran from the American military) equipped with sub Harpoon missiles. In addition the navy sought to acquire 39 Lockheed P-3 Orion maritime reconnaissance planes for ocean surveillance and anti-submarine warfare. Unlike the air force the Imperial Iranian Navy did not solely rely on American equipment and used a wide variety of suppliers. From Germany, Iran ordered 6 diesel type 209 submarines due to arrive in 1980 designed to protect Iran in the Indian Ocean. From Italy, Iran ordered 6 s, capable of anti-submarine warfare and outfitted with Otomat missiles. In 1978 Iran ordered 8 s from the Dutch, each one equipped with Mk. 46 torpedoes, Harpoon missiles and Sea Sparrow anti-aircraft missiles. In the same year Iran sought to order a further four s (similar in design to the "Korteaer" class). Iran had entered discussions with Great Britain as early as the late 1960s to purchase a nuclear powered aircraft carrier that would give Iran amphibious attack capabilities in the Indian Ocean. While initially interested in purchasing one CVA-01 aircraft carrier, which was later on cancelled by the British, Iran expressed interest in the s. Talks were in place for Iran to purchase 3 modified versions of these carriers however no official record stands to prove that such an order was placed. From France, Iran ordered 12 equipped with Harpoon missiles. Of this order, approximately 6 were delivered and the subsequent 6 cancelled.