October 6, 2020: Germany has ordered several dozen more Swedish RBS15 anti-ship missiles, mainly to be used on the three new Braunschweig-class corvettes. The RBS15 is a fire and forget anti-ship, sea-skimming, cruise missile developed by Sweden in the early 1980s. It became an export success with sales to Algeria (Mk 3), Croatia (Mk 1), Finland (Mk 2/3), Germany (Mk 3), Poland (Mk 2/3), Thailand (Mk 3).

The RBS15 Mk3 can also be used against land targets. The Mk3s for Germany are jointly produced by Sweden and Germany. The missile is available in several variants: naval (used by Swedish, Finnish, German and Polish ships), land-based truck-mounted launchers (the coastal battery) or air-launched (currently by Gripen aircraft).

RBS15 is 4.3 meters (13.8 feet) long in length, 500mm in diameter and weighs about 630 kg (800 kg with boosters for land and naval versions). Powered by a turbojet engine, like most cruise missiles, its top speed is about 12 kilometers a minute. RBS15 flies as low as possible, usually only a few meters above the waves. This means enemy ships won’t detect it on their radar until the missile is 25-45 kilometers away, depending on how high above waterline the radar is. For defense, ships use small anti-missile missiles (like ESSM) or autocannon (like Phalanx) to intercept the missile a few kilometers from the ship. Also popular are electronic defenses that try to deceive the missile terminal guidance system. These defenses have to be turned on to work and the radar operators have to be alert to these low flying missiles. Because of this factor surprise is an important factor in the success of the missile.

Max range is from 70 kilometers for the Mk 1 to 250 kilometers for the Mk 3 and 300 kilometers for Mk4. Guidance includes GPS (backed by INS) to reach the general target area and radar for detecting, identifying and homing in on the specific target. RBS15 is capable of several evasive maneuvers including re-attack if necessary. All this gives the missile a very high hit probability. The warhead is a 200 kg (440 pound) blast and fragmentation type triggered by delayed impact or proximity fuse function which is enough to cause severe damage for any target, including large warships.

A new Mk4 version was announced in 2018. The main improvements are the guidance and ECM (Electronic Countermeasures). Mk4 has a range of 300 kilometers.

RBS15 entered service in 1985 to replace 1960s RB08 and has undergone periodic upgrades ever since. Mk2 entered service in 1994 and Mk3 in 2004 as a joint German-Swedish effort. Mk4 will enter service soon. The most advanced version in service, the Mk3, costs about $4 million each. RBS15 will be replaced by a new, lighter and faster missile at the end of the 2020s.

In 2016 Sweden reintroduced truck-mounted RBS15s as coastal artillery. The number of these truck mounted (four missiles per truck) is secret. Until 2000 Sweden had about a dozen trucks carrying RBS15s but these were retired because there seemed no need. By 2014 Russia was again making threats, so the coastal batteries returned among secrecy, especially about how the truck-mounted RBS15s would receive targeting information for offshore and out of sight targets.

RBS15, like most other anti-ship missiles, competes with the American Harpoon, which entered service in 1977. RGM-84Q-4 is the latest version of Harpoon, has a  range of 248 kilometers, an all-weather radar homing guidance system and a new, lighter but more lethal warhead. The 663 kg (1,460 pound) ship-launched Harpoon has a 140 kg (308 pound) warhead and a range of 220 kilometers. It approaches the target low, at about 860 kilometers an hour. GPS gets the missile to the general vicinity of the target, then onboard radar takes over to identify and hit the target. Harpoon has successful combat experience going back two decades. Block II Harpoons have an INS backup guidance system along with several improvements to the software that make it useful against land targets as well as in coastal areas where there are a lot of islands and other geographical clutter. Each RGM-84Q-4 costs about $1.4 million.

The Swedes compete on features and a reputation for quality and reliability. While nearly 8,000 Harpoons have been built so far, RBS has sold a tenth of that. That is enough to be profitable and pay for ongoing upgrades. Several other nations also produce their own anti-ship missiles, which usually compete on price or the fact that it is locally made and more suitable for local warships.