RIM - 116 Rolling Airframe Missile The RIM - 116 Rolling Airframe Missile ( RAM ) is a small , lightweight , infrared homing surface - to - air missile in use by the American , German , South Korean , Greek , Turkish , Saudi and Egyptian navies . It was intended originally and used primarily as a point - defense weapon against anti - ship cruise missile s . The missile is so - named because it rolls around its longitudinal axis to stabilize its flight path , much like a bullet fired from a rifled barrel . It is the only US Navy Missile to operate in this manner . The Rolling Airframe Missiles , together with the Mk 49 Guided Missile Launching System ( GMLS ) and support equipment , comprise the RAM Mk 31 Guided Missile Weapon System ( GMWS ) . The Mk - 144 Guided Missile Launcher ( GML ) unit weighs and stores 21 missiles . The original weapon cannot employ its own sensors prior to firing so it must be integrated with a ship ' s combat system , which directs the launcher at targets . On American ships it is integrated with the AN / SWY - 2 Ship Defense Surface Missile System ( SDSMS ) and Ship Self Defense System ( SSDS ) Mk 1 or Mk 2 based combat systems . SeaRAM , a weapon system model equipped with independent sensors , is undergoing testing . Development . The RIM - 116 was developed by General Dynamics Pomona and Valley Systems divisions under a July 1976 agreement with Denmark and West Germany ( the General Dynamics missile business was later acquired by Hughes Aircraft and is today part of Raytheon ) . Denmark dropped out of the program , but the USN joined in as the major partner . The Mk 49 launcher was evaluated on board the in the late 1980s . The first 30 missiles were built in FY85 and they became operational on November 14 , 1992 , on board the . Service . The RIM - 116 is in service on several American and 30 German warships . All new German Navy warships will be equipped with the RAM , such as the new Braunschweig class corvette s , which will mount two RAM launchers per ship . The Greek Navy has equipped the new " Super Vita " class fast attack craft with the RAM . South Korea has signed license - production contracts for their navy ' s KDX - II , KDX - III , and Dokdo class amphibious assault ship . US Navy . The U . S . Navy plans to purchase a total of about 1 , 600 RAMs and 115 launchers to equip 74 ships . The missile is currently active aboard " Gerald R . Ford " - class aircraft carriers , " Nimitz " - class aircraft carriers , " Wasp " - class amphibious assault ships , " Tarawa " - class amphibious assault ships , " San Antonio " - class amphibious transport dock ships , " Whidbey Island " - class dock landing ships , " Harpers Ferry " - class dock landing ships , and Littoral combat ships ( LCS ) . There are plans in place to equip " Oliver Hazard Perry " - class frigates with RAM launchers . Variants . Block 0 . Also known as RIM - 116A in US service , the original version called " Block 0 " whose design is based on that of the AIM - 9 Sidewinder air - to - air missile , from which it took its rocket motor , fuze , and warhead . Block 0 missiles initially home in on active radiation emitted from a target ( such as the radar of an incoming anti - ship missile ) . Then , the terminal guidance is done by an infrared seeker derived from that of the FIM - 92 Stinger missile . In test firings , the Block 0 missiles achieved hit rates of over 95 % . Block 1 . The " Block 1 " ( RIM - 116B ) is an enhanced version of the RAM missile that adds an overall infrared - only guidance system that enables it to intercept missiles that are not emitting any radar signals . The Block 0 ' s passive radar homing capabilities have been retained . Block 2 . The RAM Block 2 is an upgraded version of the Rolling Airframe Missile ( RAM ) ship self - defense missile system . The RAM Block 2 missile upgrade aim is to more effectively counter the emerging threat of more maneuverable anti - ship missiles . The US Navy awarded Raytheon Missile Systems a $ 105 million Block 2 RAM development contract on May 8 , 2007 , with the missile development expected to complete by December 2010 . LRIP began in 2012 . 51 missiles were initially ordered . On October 22 , 2012 , the RAM Block 2 completed its third guided test vehicle flight , firing two missiles in a salvo and directly hitting the target . This verified the command and control capabilities of the system , upgraded kinematic performance , guidance system , and airframe capabilities . Raytheon is scheduled to deliver 25 Block 2 missiles during the integrated testing phase of the program . HAS Mode . In 1998 , a memorandum of understanding was signed by the defense departments of Germany and the United States to improve the system , so that it could also engage so - called " HAS " , Helicopter , Aircraft , and Surface targets . As developed , the " HAS " upgrade just required software modifications that can be applied to all Block 1 RAM missiles . SeaRAM ( weapon system ) . The SeaRAM combines the radar and electro - optical system of the Phalanx CIWS Mk - 15 Block 1B with an 11 - cell RAM launcher to produce an autonomous system - one which does not need any external information to engage threats . Like the Phalanx , SeaRAM can be fitted to any class of ship . This is still in trial stages and not currently being procured by the US Navy . In 2008 a SeaRAM system was delivered to be installed on .