Surface-to-air missile

Shown here is an artist's depiction of a Soviet surface-to-air missile system engaging western combat aircraft.

A surface-to-air missile (SAM), or ground-to-air missile (GTAM), is a missile designed to be launched from the ground to destroy aircraft or other missiles. It is one type of anti-aircraft system; in modern armed forces missiles have replaced most other forms of dedicated anti-aircraft weaponry, with the anti-aircraft cannon pushed into niche roles.

History

SA-2 Guideline surface-to-air missiles, one of the most widely deployed SAM systems in the world

Starstreak laser guided surface to air missile of the British Army.

RIM-161 of the United States Navy.

The first idea for a guided surface to air missile was in 1925, when a beam riding system was proposed whereby a rocket would follow a searchlight beam onto a target. A selenium cell would be mounted on the tip of each of the rocket's four tail fins, with the cells facing backwards. When one selenium cell was no longer in the light beam, it would be steered in the opposite direction back into the beam. The first historical mention of an actual concept and design of a surface to air missile in which an actual drawing was presented, was by inventor Dr. Gustav Rasmus in 1931: the missile would home in on to an aircraft by sound.

===World War Two=== Hunter grabs orangez

During World War II a number of efforts were started to develop surface to air missiles as it was generally considered that flak was of little use against bombers of ever-increasing performance. While the Germans developed a number of systems in an attempt to deter Allied bombing, the overwhelming air superiority held by the Allies meant that the prospect of developing similar weapons was largely ignored as unnecessary. This changed when the Kamikaze threat spread in the later half of 1944. This led to the British Fairey Stooge and Brakemine efforts, and the US Navy's SAM-N-2 Lark.

The British Army had already ordered early studies on these weapons. According to a common account of its development, possibly apocryphal, Fairey was asked to carry out some basic research on these plans by a Royal Navy request, but instead presented a revised design of some depth. The Ministry of Supply (MoS) signed a contract for development of the system in 1944. The ending of the war in August 1945 led to a lower level of urgency, but the MoS continued funding as a development project.

German efforts

Development of such weapons started in earnest in the 1940s, notably in Nazi Germany. The earliest designs were offshoots of the rocketry work being carried out by the Peenemünde teams, and started as purely paper projects. An actual design was not presented until 1940's Feuerlilie, which was followed in 1941 by Wasserfall and the Henschel Hs 117 Schmetterling. However, none of these projects saw any real development until 1943, when the first large-scale raids by Allied air fleets started. As the urgency of the problem grew, new designs were added to the mix, including Enzian and Rheintochter.

In general, these designs could be split into two groups. One group flew at low speeds, on the order of several hundred kilometers an hour, and were guided in front of the targets and then flown towards them like an aircraft. These designs included the Feuerlilie, Schmetterling and Enzian. The second group were high-speed missiles, typically supersonic, that flew directly towards their targets from below. Both used radio control for guidance, either by eye or by comparing the returns of the missile and target on a single radar screen. Development of all these systems was carried out at the same time, and the war ended before any of them was ready for combat use. In-fighting between various groups in the military also hurt development. Some extreme fighter designs, like the Komet and Natter, also overlapped with SAMs in their intended combat role.

Albert Speer was especially supportive of the missile development. In his opinion, had they been consistently developed from the start, the large scale bomber raids of 1944 would have been impossible.

Other early efforts

The United States Navy first began to study SAMs in a project known as Operation Bumblebee. This was in response to actions in which Navy ships were hit by air-launched Henschel Hs 293 glide bombs and Fritz X anti-ship missiles during 1943. Using these weapons, the launching aircraft never came within range of the ship's anti-aircraft guns, while the missiles were too small and fast to be attacked effectively. A ramjet-powered anti-aircraft missile was proposed to destroy launcher aircraft at long range. Initial performance goals were target intercept at a horizontal range of 10 miles and 30,000 feet altitude, with a 300 to 600 pound warhead for a 30 to 60 percent kill probability. Heavy shipping losses to Kamikaze attacks during the Battle of Okinawa provided additional incentive for guided missile development.

Testing began in 1945 with the PTV-N-4 Cobra, built by the Applied Physics Laboratory. However, development of the guidance, propulsion and radar systems at the same time led to long delays, and it was not until 16 years later that the RIM-8 Talos missile was cleared for operational use. In that time, the development of simpler rocket engines had led to the development of the RIM-2 Terrier, originally a weapon of severely limited performance with a range of only 19 km. Improved versions followed quickly, and the Terrier ended up taking over many of the roles that Talos was originally designed for.

The U.S. Army started their own development project, Project Nike, in 1944. They saw that their anti-aircraft artillery would be effectively useless against high-flying jet aircraft. This led to the introduction of the Nike Ajax missile in 1952, and the Nike Hercules in 1958. This was joined by the U.S. Army Air Force's 1946 requirement for an aircraft-like weapon with extremely long range, developed as part of Project Bumper. This led to the CIM-10 Bomarc with a range of over 500 km.

The title of the world's first operational surface to air missile is claimed by two systems. The first is the RSC/RSD missile, a private development by Switzerland; the second is the S-25 Berkut, developed by Soviet Russia.

The RSC-51, designated the Oerlikon Type 54 by the Swiss arms and machine tool firm Oerlikon, started as a joint project by these two Swiss firms in 1949, who kept the missile project a closely held secret from the general public till 1955, and was one of the first successful surface to air missiles that was developed,test and placed in production and could be purchased by other nations as was said then "off-the-shelf" starting in the 1951-1952 time period. But RSC-51 was never operational in a combat role: with either batches of the RSC-51 being bought for testing and evaluation, with the USAF purchasing a batch of 25, designated MX-1868, for that purpose, or as training missiles, as Japan and Italy did shortly after.

The Soviet Union began development of a SAM system in earnest with the opening of the cold war. Stalin was worried that Moscow would be subjected to US and UK bombing efforts like those against Berlin and, in 1951, demanded that a missile system to counter a 1,000 bomber raid be built as quickly as possible. This led to the S-25 Berkut system (SA-1 in NATO terminology), which was designed, developed and deployed in a rush program, thereby becoming the first SAM system to reach production and become limited-operational with a small number of units with a combat role in 1953-1954. SA-1 was only of use as a static defence against low-speed targets, but with it in place, the Soviet Union had the time to develop a follow-on system. This emerged in 1957 as the famous S-75 Dvina (SA-2), a portable system, with very high performance, that remains in operation into the 2000s. The Soviet Union remained at the forefront of SAM development throughout its history; and Russia has followed suit.

The UK followed with similar weapons, notably the RAF's Bristol Bloodhound in 1958, and the Army's English Electric Thunderbird in 1959.

Soviet surface-to-air missiles

Smaller, Faster

All of these early systems were "heavyweight" designs with limited mobility and requiring considerable set-up. However, they were also increasingly effective. By the early 1960s, deployments of SAMs had rendered high-speed high-altitude flight in combat practically suicidal. The way to avoid this was to fly lower, below the line-of-sight of missile's radar systems. This demanded very different aircraft, like the F-111, TSR-2, and Panavia Tornado, but these designs were essentially invulnerable to these larger SAM systems.

As a result, SAMs evolved rapidly in the 1960s. As their targets were now being forced to fly lower due to the presence of the larger missiles, engagements would necessarily be at short ranges, and occur quickly. Shorter ranges meant the missiles could be much smaller, which aided them in terms of mobility. By the mid-1960s almost all modern armed forces had short-range missiles mounted on trucks or light armour that could move with the armed forces they protected. Examples include the 2K12 Kub (SA-6) and 9K33 Osa (SA-8), MIM-23 Hawk, Rapier, Roland and Crotale.

The introduction of sea-skimming missiles in the late 60s and 70s led to additional mid- and short-range designs for defence against these targets. The RIM-7 Sea Sparrow was an early example, which quickly proliferated into a wide variety of designs fielded by most navies. Many of these are adapted from earlier mobile designs, but the special needs of the naval role has resulted in the continued existence of many custom missiles.

MANPADs

As aircraft moved ever lower, and missile performance continued to improve, eventually it became possible to build an effective man-portable anti-aircraft missile. Known as MANPADs, the first example was a German WWII design known as the Fliegerfaust, but it never entered operation. The performance gap between this weapon and jet fighters of the post-war era was so great that such designs would not be effective. But by the 1960s technology had closed this gap to a degree, leading to the introduction of the FIM-43 Redeye, SA-7 Grail and Blowpipe. Rapid improvement in the 1980s led to second generation designs like the FIM-92 Stinger, 9K34 Strela-3 (SA-14) and Starstreak of dramatically improved performance.

Through the evolution of SAMs, improvements were also being made to anti-aircraft artillery, but the missiles pushed them into ever shorter-range roles. By the 1980s, the only remaining widespread use was point-defense of airfields and ships, especially against cruise missiles. By the 1990s, even these roles were being encroached on by new MANPAD and similar weapons.

General information

Surface-to-air missiles are classified by their guidance, mobility, altitude and range.

Man-portable air-defense systems (MANPADS) are the smallest of SAMs and are capable of being carried and launched by a single person and thus suitable for local air defence, such as against attack helicopters. They are sometimes attached to vehicles in order to increase their mobility. Generally, MANPADS have a range of around five kilometres (three miles). Soviet MANPADS have been exported around the world and can still be found in many of their former client states. Other nations have developed their own MANPADS.

Larger land-based SAM's can be deployed from fixed installations or mobile launchers. In the case of mobile launchers, they are either wheeled or tracked. The tracked vehicles are usually armored vehicles specifically designed to carry SAMs. Larger SAMs may be deployed in fixed launchers, but can be towed/re-deployed at will. The range of mobile SAMs varies greatly, from just over a dozen to several hundred kilometres. For example, the Russian S-400 has a range of 400 km.

Ship-based SAMs are also considered surface-to-air. Virtually all surface warships can be armed with SAMs. In fact, naval SAMs are a necessity for all front-line surface warships. Some warship types specialize in anti-air warfare e.g. Ticonderoga-class cruisers equipped with the Aegis combat system or Kirov class cruisers with the S-300PMU Favorite missile system.

Target acquisition

Main article: Missile guidance

Targets for non-MANPAD SAMs will usually be acquired by air-search radar, then tracked before or while a SAM is "locked-on" and then fired. Potential targets, if they are military aircraft, will be identified as friend or foe before being engaged.

See also

• Anti-aircraft warfare
• Man-portable air-defense system
• Missile guidance
• List of NATO reporting names for surface-to-air missiles
• List of surface-to-air missiles
• SEAD, Suppression of Enemy Air Defenses, the mission of finding and destroying SAM and AA gun installations. The SEAD mission in the United States Air Force is designated “Wild Weasel”.

External links

• Rest-of-World Missile Systems from the Federation of American Scientists website