Same missile, three names, depending on who launches it

One missile, three names

A US missile's code does not describe the weapon. It describes the circumstance: where it launches from, what kind of target it hits, what kind of object it is. When the same missile launches from different places, it gets different codes — even though the engine, warhead and electronics stay identical.

Harpoon is the cleanest case. Under design number 84, the registry lists nine different codes for the same missile family: AGM-84 from an aircraft, RGM-84 from a ship, UGM-84 from a submarine, plus ATM-84, CATM-84, DATM-84, NAEM-84, RTM-84 and UTM-84 — training and test variants, each with its own status letter. Nine names for one missile program.

Tomahawk follows the same pattern, with an exception that shows the rulebook doesn't always follow itself. The ship-launched version is RGM-109, the submarine version UGM-109. The American ground-mobile version, Gryphon, should have been MGM-109G — the letter M means "ground launched, mobile." It stayed BGM-109G, the letter the Navy already used for the whole Tomahawk family before each launch environment got its own letter. Nobody ever corrected it.

The code is exactly three letters plus a design number, and the order is fixed: launch environment, then mission, then vehicle type. AIM-9 means launched from the air, on an intercept mission, a guided missile. An optional prefix ahead of the three letters marks a round as merely experimental, captive (carried but not fired), or a plain training dummy.

Decode any code

Pick the letters and see what each position means — and whether a real missile ever carried exactly that combination.

What each letter means

Position matters as much as the letter. M in the middle means ground-launched, mobile; M at the end means guided missile; M as a status prefix once meant "under maintenance" — the only letter ever retired from the system, dropped in 1993. The tables below give the meaning at each position, with the year each letter has been valid since.

Of the 14 possible mission letters, exactly one is new: H, for "high-speed, hypersonic." It is absent from the Air Force's official 2020 list. A memorandum dated 25 March 2025 added the mission, but does not spell out which letter marks it — the letter H is inferred from a single real case, AHM-4A, the HACM hypersonic missile. It is the only entry in the whole registry carrying mission H.

From chaos to three letters

Before 1963, each armed service kept its own registry, and the same missile could carry three different names within a few years. The Navy's Sparrow missile was first AAM-N-2, then, once the Air Force adopted it, AIM-101 — a code with no relation to the Navy's, for the exact same weapon. Minuteman was SM-80. A period field guide needed three separate tables just to identify one missile, depending on which service flew it.

1. 1941–1962

   Every service invents its own registry: the Army Air Forces' wartime categories (BG, BQ, GB, JB, VB), the Navy's K-series from 1946, then the 1947 joint system with separate numbering per service. By 1962, the same missile can carry entirely different codes at the Navy and the Air Force.

2. 11 December 1962

   Department of Defense Directive 4000.20 calls for one registry, shared by all three services, for missiles and guided weapons.

3. 27 June 1963

   The new system takes effect. Every missile already in service is renamed at once — Minuteman goes SM-80 → LGM-30, Sidewinder goes AAM-N-7 → AIM-9.

4. 1969

   Letter F is added, for a weapon carried and fired by a single soldier — Redeye, later Stinger.

5. 1976

   Letter G is added, for runway launch.

6. 1978–1986

   Status prefixes C (captive) and D (dummy) are added.

7. 1988–1989

   The biggest expansion: the registry absorbs space vehicles — vehicle-type letters B (booster) and S (satellite), launch environment S (space), and missions C, L, M, N, S.

8. 1993

   Status prefix M (maintenance) falls out of use. It remains the only letter ever retired from the system.

9. 1997

   Reusable drones leave the missile series for their own registry, the Q series, inside the aircraft naming system — from then on, Predator is RQ-1, not a missile.

10. 3 November 2020

    The last full rewrite of the rulebook, as Department of the Air Force Instruction 16-401.

11. 25 March 2025

    A memorandum adds the "high-speed, hypersonic" mission — the first real addition to the letter list since 1989.

All 315 active codes

Every line below is a distinct letter-and-number code, exactly as it appears in the registry consulted: a missile with four launch environments, like Harpoon, occupies four lines under the same design number, 84. A code with a status prefix — training, test, dummy — occupies a line separate from its operational form. The search box filters by name or manufacturer.

Load 25 more of 290

The registry's own oddities

A rulebook kept for 63 years accumulates exceptions.

A jump with no explanation. Design numbers climb in order, from 1 to 424 — but the newest known code, AIM-424 ("Malice," Raytheon), jumps straight from the 260s to 424, with no explanation in the source consulted.

A recovered slot. Number 146 is taken — MIM-146 exists — but 147 sat apparently unassigned for years before resurfacing as MIM-147A, for an unidentified Navy or Marine Corps missile. The source consulted says plainly that it does not know which missile this refers to. One unconfirmed guess ties it to Tamir, the interceptor of Israel's Iron Dome system.

A false legend. A few older sources mention a code RIM-35 for the Talos anti-aircraft missile. It never existed: Talos's real code is RIM-8, and the confusion comes from an unrelated drone project that briefly carried the letter Q.

A number skipped out of superstition. In the separate military satellite series, the number 13 is deliberately missing — "triskaidekaphobia," the source consulted calls it: the old fear of the number 13.

A rule broken by its own author. Gryphon, the ground-launched Tomahawk, still carries the letter of a family it should have left behind — BGM-109G instead of MGM-109G — because nobody updated it after the rule changed.

Method and limits

The letter tables and the 315 codes above come from Current Designations of U.S. Unmanned Military Aerospace Vehicles, Andreas Parsch's compilation at designation-systems.net, last updated 23 August 2026 — the reference source Wikipedia, F-16.net and GlobalSecurity.org all lean on for this subject. Parsch in turn cites the official rulebook, Department of the Air Force Instruction 16-401 (3 November 2020), and the 25 March 2025 memorandum. An attempt to download the official rulebook directly from the Air Force's own server was blocked; the letter H above is therefore attributed to Parsch, verified by reading his page directly, not the rulebook itself.

Counting unit: one code means one distinct combination of letters and design number, exactly as it appears as its own line in the source — not one missile program (Harpoon is one program, nine codes) and not one series-letter variant (AIM-9A and AIM-9B are one code, AIM-9, with different series letters). Of the 315, 143 — nearly half — start with the letter A, air launch. The real launch-and-mission combinations, ignoring the status prefix, number 44 out of a possible 168: just over a quarter of the rulebook has ever actually been used.

The decoder checks a combination only against this corpus of 315 guided missiles. It does not cover unguided rockets, probes, boosters or satellites, which use the same launch and mission letters but different vehicle-type letters, in their own separate registries.

The thread that started this piece: Christopher Wipper (@SGTWipper1Each) on X, laying out the same three letters in brief.

Sources

• Andreas Parsch, Current Designations of U.S. Unmanned Military Aerospace Vehicles, designation-systems.net, updated 23 August 2026 — the letter tables and the 315 codes.
• Department of the Air Force, Instruction 16-401, Designating and Naming Military Aerospace Vehicles, 3 November 2020, cited by the source above; direct access to the official file was blocked at verification.
• Wikimedia Commons — photographs, with author and licence under each.

Every number in the text is computed from the same registry behind the decoder and the table. What the source does not say, the page does not say either: for codes without a public name, the table shows exactly what the registry shows.