US Missile Designations

The system dates from 1963, when the Department of Defense replaced the separate Army, Navy and Air Force schemes with one joint standard, now carried by the tri-service instruction AFI 16-401 / AR 70-50 / NAVAIRINST 13100.16 (the list of assigned designations was published as DoD 4120.15-L until 2018). A designation decodes best right to left: the third letter is the vehicle type (M guided missile, R unguided rocket, N probe, B booster, S satellite), the second is the mission (G surface attack, I aerial intercept, U underwater attack, D decoy, E electronic, Q drone, T training, among others) and the first is the launch environment: A air, R surface ship, U underwater, M mobile ground launcher, L silo, H silo-stored but lifted to fire, C coffin shelter, F individual soldier, G runway, P soft pad, B multiple environments, S space. The design number runs in one sequence per vehicle type, which is why an AGM-158 and a RIM-156 are neighbours; the series letter after it marks each production version, A first, skipping I and O. A variant that changes platform keeps its number and swaps the first letter: AIM-7 Sparrow and RIM-7 Sea Sparrow, AGM-84, RGM-84 and UGM-84 Harpoon. A status prefix in front of the whole string marks a non-service round: X experimental, Y prototype, Z planning, C captive, D dummy, J or N special test. The popular name (Sidewinder, Tomahawk, Sentinel) is assigned separately and usually stays with the design, though some versions take their own (Gryphon, LRASM).

One lane per missile family, one dot per missile entering service. The pre-1963 systems were renumbered into the joint scheme, so the Sidewinder keeps its 1956 date under the AIM-9 label it only received seven years later. The lanes fill evenly through the Cold War, thin out in the 1990s, and pick up again after 2010 with the long-range and hypersonic programmes: SM-6, LRASM, PrSM, Dark Eagle, AIM-174B and, planned for 2030, the Sentinel.

The AIM line started under two service schemes: the Navy's AAM-N-7 Sidewinder and AAM-N-6 Sparrow, the Air Force's GAR-1 Falcon, all renumbered in 1963. Two lineages carry most of the catalogue since: the infrared Sidewinder, whose AIM-9L of 1978 brought all-aspect engagement and whose AIM-9X of 2003 is the current version, and the radar line that ran from the semi-active Sparrow to the active-radar AIM-120 AMRAAM in 1991. The long-range slot left empty by the Phoenix in 2004 was filled in 2024 by the AIM-174B, a Standard Missile SM-6 adapted to the Super Hornet, while the AIM-260 JATM is designed to replace the AMRAAM.

AGM is the largest family because it covers every air-launched missile aimed at the surface: the tactical Bullpup, Maverick and Hellfire, the anti-radar line from the Shrike to the AGM-88G AARGM-ER, and the strategic cruise missiles. The AGM-158 shows how far one design number stretches: AGM-158A is the JASSM, AGM-158B the extended-range version with a new engine, AGM-158C the anti-ship LRASM with its own seeker, and AGM-158D a further extended-range development. The nuclear AGM-86B of 1981 is to be replaced by the AGM-181A LRSO, whose prototypes flew as YAGM-181A.

The Navy adds its own layer of names on top of the designations. The Standard Missile family is counted SM-1 to SM-6, but each major redesign took its own number: RIM-66 for the medium-range SM-1 and SM-2, RIM-67 and RIM-156 for the extended-range versions, RIM-161 for the SM-3 ballistic-missile interceptor built on the SM-2 Block IV airframe, and RIM-174 for the SM-6, which pairs that airframe with an AMRAAM-derived active seeker. The SM-4 land-attack version, RGM-165, was cancelled in 2002. The Tomahawk kept one number instead: designated BGM-109 because it was to be fired from ships, submarines and ground launchers, it was split into RGM-109 and UGM-109 in 1986, while the ground-launched Gryphon kept BGM-109G. Anti-submarine weapons take the U mission letter — RUR-5 ASROC, UUM-44 SUBROC — and the submarine-launched ballistic line runs UGM-27 Polaris, UGM-73 Poseidon, UGM-96 Trident I, UGM-133 Trident II.

The first letter separates the Army's mobile batteries (MIM-23 Hawk, MIM-104 Patriot) from the shoulder-fired FIM-43 Redeye and FIM-92 Stinger and from the fixed sites of the Cold War: the LIM-49 Spartan of the Safeguard anti-ballistic system and the CIM-10 Bomarc, stored horizontally in coffin shelters. The Patriot is one designation across very different rounds — MIM-104A to E for the original and PAC-2 missiles, the smaller hit-to-kill PAC-3 and PAC-3 MSE listed as MIM-104F. THAAD and the Sprint interceptor of 1975 never received a designation of their own, and the NASAMS system fires the air-launched AIM-120 from a ground launcher.

The ICBM letters record how the missile is based. The Atlas moved from coffin shelters (CGM-16D and E) to a silo it was lifted out of (HGM-16F); the Titan I was HGM-25A for the same reason and the Titan II, fired from inside its silo, LGM-25C. Every Minuteman is LGM-30 — A and B for Minuteman I, F for Minuteman II, G for the Minuteman III deployed since 1970 — and its replacement is the LGM-35A Sentinel. The Peacekeeper was MGM-118A while a mobile basing was planned and became LGM-118A when it went into silos. On the Army side, the leading M marks the mobile launcher: MGM-140 ATACMS and its PrSM successor, which like the Dark Eagle hypersonic weapon has no designation yet. The TOW is BGM-71 because it is fired from tripods, vehicles and helicopters alike.