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Boeing SLAM-ER

Boeing · Cruise · USA · Modern (1992–2009)

The AGM-84H/K SLAM-ER (Standoff Land Attack Missile — Expanded Response) is an American precision-strike cruise missile derived by Boeing from the Harpoon anti-ship missile. For roughly 25 years it has served as the principal long-range precision land-attack weapon for the US Navy, USAF and several allied air arms. Boeing developed the original SLAM (AGM-84E) between 1988 and 1992, then the improved SLAM-ER (AGM-84H/K) from 1996 to 2000, with service entry in 2000. About 1,200 SLAM-ER rounds have been built. Users include the US Navy, Republic of Korea Air Force, Republic of Korea Navy, JMSDF and others.

Power comes from a single Teledyne CAE J402 turbojet — the same engine fitted to the Harpoon. Maximum speed is Mach 0.85 and range is 280 km, against 124 km for the Harpoon and 110 km for the baseline SLAM. The missile is 4.5 m long and weighs 730 kg. Its 360 kg WDU-40/B penetrator with blast-fragmentation effect is markedly heavier than the Harpoon's 221 kg charge. Guidance combines GPS and INS for midcourse with an imaging-infrared Wide-Field-of-View seeker, paired with Aided Target Recognition for autonomous identification. A two-way datalink lets the launch crew steer the missile via the seeker image in the terminal phase, or hand off the engagement to the missile's own ATR logic. Carrier aircraft include the F/A-18, P-3, P-8, and — for export users — the F-15K and F-16C.

Combat use began in 2000 when US Navy F/A-18s fired SLAM-ERs against Iraqi targets during Operation Southern Watch. Around 50 rounds were launched in the 2003 Operation Iraqi Freedom campaign, followed by employment over Libya in 2011 and against ISIS from 2014 onwards. The Republic of Korea Navy and Air Force hold the weapon for standoff strikes against North Korean leadership and missile sites — South Korea is the largest export customer, with the SLAM-ER serving as the primary precision-strike weapon on Korean F-15K and F-16C aircraft. The type is being progressively replaced by the AGM-158C LRASM, the future Maritime Strike Tomahawk and the JSM (Joint Strike Missile), but production continues at Boeing St. Louis through about 2030.

For Kids — a shorter, friendlier version

The SLAM-ER is a cruise missile made by Boeing. Its full name is the Standoff Land Attack Missile – Expanded Response. It is used by the American Navy and Air Force, as well as some allied countries. The missile has been in service since the year 2000.

The SLAM-ER grew out of an older missile called the Harpoon. The Harpoon was built to hit ships. Boeing changed the design so it could hit targets on land instead. Development of the improved SLAM-ER version started in 1996 and finished in 2000.

This missile is longer than a small car, stretching about 4.5 meters from nose to tail. It weighs around 730 kilograms. It can fly nearly as fast as the speed of sound and has a range of 280 kilometers. That is more than twice as far as the original Harpoon could travel.

The SLAM-ER uses a smart guidance system. GPS and a camera in the nose help it find its target. A pilot can watch a live video feed and steer the missile in its final moments. Or the missile can find and track the target all on its own.

About 1,200 SLAM-ER missiles have been built. It can be launched from aircraft like the F/A-18 and the P-8. South Korea and Japan also use this missile to protect their countries.

Fun Facts

The SLAM-ER can hit a target 280 kilometers away — that is farther than the distance from Los Angeles to San Diego!
It uses the same engine as the Harpoon anti-ship missile that inspired it.
The SLAM-ER is longer than a small car, measuring 4.5 meters from end to end.
A pilot can watch live camera video from the missile and steer it to the target.
The missile can also fly and find its target all by itself without any help from a pilot.
About 1,200 of these missiles have been built since the year 2000.
The SLAM-ER can fly at around 85 percent of the speed of sound.
South Korea and Japan both use the SLAM-ER alongside the American military.

Kids’ Questions

How is the SLAM-ER different from the Harpoon missile?

The Harpoon was made to hit ships at sea. Boeing redesigned it to hit targets on land. The SLAM-ER can also fly more than twice as far as the Harpoon. It also carries a heavier explosive charge.

How does the SLAM-ER find its target?

The missile uses GPS and a camera in its nose to guide itself. A pilot can watch the live camera feed and steer it at the end. The missile can also spot and track the target all on its own using smart computer software.

What planes can carry the SLAM-ER?

The SLAM-ER can be launched from the F/A-18 fighter jet and the P-8 patrol plane. South Korea also flies it on the F-15K fighter. These planes carry and release the missile before it flies the rest of the way to the target.

Variants

AGM-84E SLAM (1992): Original variant. 110 km range. Retired.
AGM-84H/K SLAM-ER (2000): Current variant. 280 km range with IIR seeker.

Notable Operators

US Navy + USAF (2000-present): Principal operator. F/A-18 and P-8 carriage.
Republic of Korea Air Force + Navy: Largest export customer. F-15K and F-16C carriage.

Frequently Asked Questions

How does SLAM-ER differ from Harpoon?

SLAM-ER and Harpoon share the same airframe, engine and general layout but differ in mission, sensor and warhead. (1) Mission — Harpoon is a sea-skimming anti-ship weapon, while SLAM-ER attacks fixed land targets using a varied-altitude flight profile and terminal manoeuvre. (2) Sensor — Harpoon uses active radar terminal homing suited to ships at sea; SLAM-ER uses an imaging-infrared (IIR) seeker that picks out land targets against ground clutter. (3) Warhead — Harpoon's 221 kg penetrator is shaped for ship hulls, whereas SLAM-ER's 360 kg WDU-40/B penetrator and blast charge is sized for hardened ground targets. (4) Range — Harpoon reaches around 124 km, SLAM-ER around 280 km, gained through aerodynamic refinements and a higher-altitude cruise. SLAM-ER also accepts mid-flight target updates over a two-way datalink, so controllers can retarget or abort the missile in flight.

Sources

Wikipedia — AGM-84H/K SLAM-ER