The RUR-5 ASROC (for "Anti-Submarine Rocket") is an all-weather, all sea-conditions anti-submarine missile system. Developed by the United States Navy in the 1950s, it was deployed in the 1960s, updated in the 1990s, and eventually installed on over 200 USN surface ships, specifically cruisers, destroyers, and frigates. The ASROC has been deployed on scores of warships of many other navies, including Canada, Germany, Italy, Japan, the Republic of China, Greece, Pakistan and others. History ASROC started development as the Rocket Assisted Torpedo (RAT) program by the Naval Ordnance Test Station at China Lake in the early 1950s to develop a surface warship ASW weapon to counter the new post-World War II submarines which ran quieter, at much higher speed and could attack from much longer range with high speed homing torpedoes. In addition, the goal was to take advantage of modern sonars with a much larger detection range. An extended range torpedo delivered by parachute from the air would allow warships the stand-off capability to attack hostile submarines with very little advance notice to the hostile submarine. The RAT program came in three phases: RAT-A, RAT-B and RAT-C. RAT-A and its follow-on, RAT-B, were compact and economical stand-off weapons for smaller warships, but were determined to be either unreliable or had too short a range. RAT-C was developed as a stand-off ASW weapon that used a nuclear depth charge. This required a range of at least to escape potential damage from the underwater blast. The RAT-C was considerably larger than the previous RAT program rockets to accommodate the extended range needed and was for larger warships. After the failure of both the RAT-A and RAT-B programs, RAT-C was redesigned to use not only a nuclear depth charge but also a homing ASW torpedo. To obtain the accuracy needed, the RAT-C rocket launcher had to be redesigned with larger side fins. This program finally combined reliability and accuracy, along with the required stand-off range. Before RAT-C reached operational status in 1960, aboard the large US Navy destroyer leader , its name was changed to ASROC. ASROC was deployed in 1961 and eventually made the majority of USN surface combatants nuclear-capable. Description The first ASROC system using the MK-112 "Matchbox" launcher was developed in the 1950s and installed in the 1960s. This system was phased out in the 1990s and replaced with the RUM-139 Vertical Launch ASROC, or "VLA". After a surface