The Standard Missile-6 (SM-6) offers US and allied forces a powerful capability with an extended range that reaches well beyond the horizon, significantly expanding the reach and lethality of modern naval forces.

The RIM‑174 Standard Extended Range Active Missile, or SM‑6, has been transforming the US Navy’s air defense since entering service in 2013.

Built on the proven airframe and propulsion systems of earlier Standard Missile variants, the SM-6 stands apart by uniting anti-air, anti-surface and terminal ballistic missile defense roles in one platform.

This multi-mission flexibility allows surface ships to defend against airborne and ballistic threats as well as striking targets at sea -- delivering enhanced firepower without the need for multiple specialized systems.

All the Standard Missile variants enable multi-tiered naval air defense. SM-2 is used to engage aircraft and cruise missiles in the terminal phase, while SM-3 destroys incoming ballistic missiles during the midcourse phase of flight.

SM-6 was built on the airframe of the earlier SM‑2ER Block IV. It integrates an active radar homing seeker, dramatically enhancing its ability to engage agile aircraft, drones, cruise missiles and even ballistic missile threats.

With advanced guidance and flexible targeting, SM‑6 is not intended to replace the SM‑2 series, but rather to augment it. It delivers longer reach, greater firepower and the ability to take on a wider set of threats in a single platform.

The missile can be employed in several modes, from traditional semi-active radar homing to over-the-horizon strikes using Cooperative Engagement Capability (CEC), a real-time sensor network developed by the US Navy.

Two-stage construction

SM‑6 is a two-stage, solid-fueled missile, powered first by a Mk 72 booster and then by a sustainment motor that carries it to its target.

It can be launched in several ways, by using inertial guidance with terminal active homing, fully semi-active radar tracking or over-the-horizon targeting through CEC networks.

This versatility allows it to intercept airborne threats, support ballistic missile defense missions alongside the SM‑3 or pivot to a high-speed strike role against surface targets at sea.

When cued by ship sensors or off-board platforms, SM-6 conducts a terminal dive onto surface vessels with precision.

The missile is well-suited for high–altitude threats and sea-skimming attacks.

It uses a Mk 125 blast‑fragmentation warhead and dual-mode seeker to discriminate between land-based cruise missiles and clutter, tracking them even when concealed behind terrain.

US Navy cruisers and destroyers use the Aegis Combat System to integrate the SM-2, SM-3, SM-6, Evolved Sea Sparrow Missile (ESSM) and other defense systems.

The Aegis Combat System uses a complex array of radars and sensors to track, identify and destroy adversary targets, and helps to defend naval ships against hostile aircraft and cruise missile threats.

The SM-6 effectively extends Aegis' protective umbrella with its active seeker and CEC link, which enable engagements beyond the firing ship's own radar horizon.

The missile marks a leap in naval air defense reach compared to older SM‑2 variants. It has a range of at least 240km, although some industry experts estimate it can go much farther.

Domain flexibility

The SM‑6's design flexibility extends to other domains.

Its air-to-air version, the AIM‑174B Gunslinger, is carried by F/A-18E/F Super Hornets. AIM-174, still in the testing phase, retains SM‑6's active seeker and can launch from altitude to engage aircraft beyond the range of some other missiles.

The US Army's Typhon Strategic Mid‑Range Fires (SMRF) system uses the Mk 41 containerized launcher to fire SM‑6 in surface-to-surface and air defense roles from land.

The army achieved successful SM‑6 and Tomahawk launches from the Typhon Weapon System in 2023 and deployed the system to the Philippines in 2024.

The SM‑6 delivers useful versatility to respond to emerging threats, from increasingly long-range anti-ship missiles to cruise and ballistic missile barrages.

Its active seeker, long reach and networked targeting reinforce multi-domain defense capabilities -- whether afloat, in the air or ashore.