Cruise missiles

A cruise missile is an unmanned self-propelled guided missile that sustains flight through aerodynamic lift for most of its flight path. Cruise missiles are designed to deliver a large payload over long distances with high precision. Modern cruise missiles are capable of traveling at high subsonic, supersonic, or hypersonic speeds, are self-navigating, and are able to fly on a non- ballistic, extremely low-altitude trajectory.

History

The idea of an "aerial torpedo" was shown in the British 1909 film '' The Airship Destroyer'' in which flying torpedoes controlled wirelessly are used to bring down airships bombing London.

In 1916, the American aviator Lawrence Sperry built and patented an "aerial torpedo", the Hewitt-Sperry Automatic Airplane, a small biplane carrying a TNT charge, a Sperry autopilot and barometric altitude control. Inspired by the experiments, the United States Army developed a similar flying bomb called the Kettering Bug. Germany had also flown trials with remote-controlled aerial gliders ''( Torpedogleiter)'' built by Siemens-Schuckert beginning in 1916.

In the Interwar Period, Britain's Royal Aircraft Establishment developed the Larynx (Long Range Gun with Lynx Engine), which underwent a few flight tests in the 1920s.

In the Soviet Union, Sergei Korolev headed the GIRD-06 cruise missile project from 1932 to 1939, which used a rocket-powered boost- glide bomb design. The 06/III (RP-216) and 06/IV (RP-212) contained gyroscopic guidance systems. The vehicle was designed to boost to altitude and glide a distance of , but test flights in 1934 and 1936 only reached an altitude of .

In 1944, during World War II, Germany deployed the first operational cruise missiles. The V-1, often called a flying bomb, contained a gyroscope guidance system and was propelled by a simple pulsejet engine, the sound of which gave it the nickname of "buzz bomb" or "doodlebug". Accuracy was sufficient only for use against very large targets (the general area of a city), while the range of was significantly lower than that of a bomber carrying the same payload. The main advantages were speed (although not sufficient to outperform contemporary propeller-driven interceptors) and expendability. The production cost of a V-1 was only a small fraction of that of a V-2 supersonic ballistic missile with a similar-sized warhead. Unlike the V-2, the initial deployments of the V-1 required stationary launch ramps which were susceptible to bombardment. Nazi Germany, in 1943, also developed the Mistel composite aircraft program, which can be seen as a rudimentary air-launched cruise missile, where a piloted fighter-type aircraft was mounted atop an unpiloted bomber-sized aircraft that was packed with explosives to be released while approaching the target. Bomber-launched variants of the V-1 saw limited operational service near the end of the war, with the pioneering V-1's design reverse-engineered by the Americans as the Republic-Ford JB-2 cruise missile.

Immediately after World War II, the United States Air Force had 21 different guided missile projects, including proposed cruise missiles. By 1948, all but four of these projects had been canceled: the Air Materiel Command Banshee, the SM-62 Snark, the SM-64 Navaho, and the MGM-1 Matador. The Banshee design was similar to Operation Aphrodite; like Aphrodite, it failed, and was canceled in April 1949. Concurrently, the US Navy's Operation Bumblebee, was conducted at Topsail Island, North Carolina, from c. 1 June 1946, to 28 July 1948. Bumblebee produced proof-of-concept technologies that influenced the US military's other missile projects.

During the Cold War, both the United States and the Soviet Union experimented further with the concept, of deploying early cruise missiles from land, submarines, and aircraft. The main outcome of the United States Navy submarine missile project was the SSM-N-8 Regulus missile, based upon the V-1 but powered by an Allison J33 jet engine. The Regulus entered service but was phased out with the advent of submarine launched ballistic missiles that did not require the submarine to surface in order to launch the missile and guide it to its target.

The United States Air Force's first operational surface-to-surface missile was the winged, mobile, nuclear-capable MGM-1 Matador, also similar in concept to the V-1. Deployment overseas began in 1954, first to West Germany and later to the Republic of China and South Korea. On 7 November 1956, the U.S. Air Force deployed Matador units in West Germany, whose missiles were capable of striking targets in the Warsaw Pact, from their fixed day-to-day sites to unannounced dispersed launch locations. This alert was in response to the crisis posed by the Soviet attack on Hungary which suppressed the Hungarian Revolution of 1956.

Between 1957 and 1961 the United States followed an ambitious and well-funded program to develop a nuclear-powered cruise missile, Supersonic Low Altitude Missile (SLAM). It was designed to fly below the enemy's radar at speeds above Mach 3 and carry hydrogen bombs that it would drop along its path over enemy territory. Although the concept was proven sound and the engine finished a successful test run in 1961, no airworthy device was ever completed. The project was finally abandoned in favor of ICBM development.

While ballistic missiles were the preferred weapons for land targets, heavy nuclear and conventional weapon tipped cruise missiles were seen by the USSR as a primary weapon to destroy United States naval carrier battle groups. Large submarines (for example, Echo and Oscar classes) were developed to carry these weapons and shadow United States battle groups at sea, and large bombers (for example, Backfire, Bear, and Blackjack models) were equipped with the weapons in their air-launched cruise missile (ALCM) configuration.

Categories

Cruise missiles can be categorized by payload/warhead size, speed, range, and launch platform. Often variants of the same missile are produced for different launch platforms (for instance, air- and submarine-launched versions).

Guidance systems can vary across missiles. Some missiles can be fitted with any of a variety of navigation systems ( Inertial navigation, TERCOM, or satellite navigation). Larger cruise missiles can carry either a conventional or a nuclear warhead, while smaller ones carry only conventional warheads.

Hypersonic

A hypersonic cruise missile travels at least five times the speed of sound (Mach 5).

* 3M22 Zircon (>1000–1500 km) – hypersonic anti-ship cruise missile

* ASN4G (Air-Sol Nucléaire de 4e Génération) – scramjet-powered hypersonic cruise missile being developed by France
*BrahMos-II (≈800–1500 km) / – hypersonic cruise missile under development in India and Russia

*Hycore (South Korea)
* HSTDV – hypersonic scramjet demonstrator. A carrier vehicle for hypersonic long-range cruise missiles is being developed by Defence Research and Development Organisation (DRDO).
*Hyfly-2 – hypersonic air-launched cruise missile first displayed at Sea Air Space 2021, developed by Boeing
* Hypersonic Air-breathing Weapon Concept (HAWC, pronounced Hawk) – scramjet-powered hypersonic air-launched cruise missile without a warhead that uses its own kinetic energy upon impact to destroy the target, developed by DARPA
* Hypersonic Air Launched Offensive Anti-Surface (HALO) – air-launched anti-ship missile under Offensive Anti-Surface Warfare Increment 2 (OASuW Inc 2) program for the US Navy (Navy)
* Hypersonic Attack Cruise Missile (HACM) – planned for use by the United States Air Force
* SCIFiRE / – Southern Cross Integrated Flight Research Experiment (SCIFiRE) is a joint program between the US Department of Defense and the Australian Department of Defence for a Mach 5 scramjet-powered missile. In September 2021, the US Department of Defense awarded Preliminary Design Review contracts to Boeing, Lockheed Martin and Raytheon Missiles & Defense.

Supersonic

These missiles travel faster than the speed of sound, usually using ramjet engines. The range is typically 100–500 km, but can be greater. Guidance systems vary.

Examples:
* ASALM US ALCM prototype, test-flown to hypersonic Mach 5.5
* 3M-54 Kalibr (4,500 km, Mach 3) (the "Sizzler" variant is capable of supersonic speed at the terminal stage only)
* 3M-51 Alfa (250 km, Mach 2.5)
* Air-Sol Moyenne Portée (300–500 km+, Mach 3)  – supersonic stand-off nuclear missile
* ASM-3 (400 km, Mach 3+)
*BrahMos