Missiles

views updated Jun 11 2018

Missiles. Airborne missiles were experimented with in World War I and used extensively in World War II. Since then a wide variety of airborne missiles have been tested in combat many times. Their performance has continuously improved because of technological advances in aerodynamics, guidance, propulsion, and warheads.

Air‐to‐Air Missiles.

The very first air‐to‐air missile was an aircraft rocket designed primarily for antiballoon or anti‐Zeppelin work. Invented by Lt. Y. P. G. Le Prieur of the French Naval Air Service, the rocket came into use in 1916 by both the French and British air forces. Four or five projectiles, each with a Congreve rocket‐like stick for stability, were connected to interplane struts on either side of biplane fighters. Salvoed by electric ignition, the unguided rockets were most effective against larger targets such as observation balloons, but successes were also scored against other aircraft.

World War II brought about the widespread use of aerial rockets, primarily as an air‐to‐ground weapon against armor. Early in the war, the Germans used fighters to lob a rather primitive conversion of their 21cm mortar shells to break up bomber formations. Later, twenty‐four to forty‐eight R4M rockets were carried under the wings of a Messerschmitt Me 262 jet fighter. Salvo‐fired, they dispersed to cover an area about the size of a football field; a single hit was deadly.

During World War II, the Germans developed radio‐controlled and wire‐guided versions of the Henschel Hs 298, and the supersonic wire‐guided X‐4, designed by Dr. Max Kramer in 1943. Both missiles were intended to have proximity fuses, with the X‐4 testing an acoustic version. Their most important legacy was probably in proving the feasibility of wire guidance, which has been so widely used on antiarmor rocket weapons.

The Cold War requirement to shoot down incoming nuclear bomb–laden enemy bomber aircraft created a demand within the U.S. Air Force for air‐to‐air missiles for its interceptors. The Lockheed F‐94 Starfighter and North rop F‐89 Scorpion were initially armed with 2.75‐inch‐ diameter unguided aerial rockets. These were supplemented by the Hughes GAR (later AIM) Falcon and the McDonnell‐Douglas MB‐1 (AIR‐2A) Genie. The latter was an unguided rocket with a speed of Mach 3, a range of 6 miles, and a 1.5‐kiloton warhead intended to break up formations of incoming bombers. Aircraft carrying the Genie were routinely parked at civil airports during the years of the Air Defense Command dispersal program, a practice that might have disturbed modern environmentalist sensibilities.

The long‐lived Hughes Falcon was a short‐ to medium‐range missile capable of Mach 4 speed and a range of about 7 miles. Guidance was by a Hughes‐developed semiactive radar homing system.

Missile design improved rapidly as better propellants, miniaturized circuitry, and improved systems came into being. A series of American missiles appeared that would continue in service for decades and be used in air forces around the world. Foreign industries arrived at similar solutions, and their designs were similarly long‐lived and widely used.

The heat‐seeking AIM‐9 Sidewinder first flew in September 1953, and continues in use today, after more than 110,000 have been produced. The successful and widely used Soviet AA‐2A Atoll was developed directly from captured Sidewinders. Missiles similar in principle and performance to the Sidewinder have also been built in China, France, Germany, Italy, Israel, and South Africa.

The 186‐pound AIM‐9 has been produced in many variants, but may be described in general as a solid fuel rocket with a Mach 2 speed and a range of 10 miles. The infrared homing device detects a target's heat source (e.g., a jet aircraft's tailpipe) and homes in on it. Raytheon and Loral are the primary contractors.

A second long‐lived air‐to‐air missile is the AIM‐7 Sparrow, a semiactive Döppler radar‐guided medium‐range missile that was first flown in 1952 and came into operational use in 1958. It has a maximum speed of Mach 3.5 and a range of 25 miles. More than 40,000 had been built when production ended in 1990. Principal contractors include Raytheon and Hughes Missile Systems. The Sparrow was effective during the Persian Gulf War in Operation Desert Storm, shooting down twenty‐three aircraft.

The 510‐pound Sparrow carries an 86‐pound warhead. The target is first acquired by the carrier's radar; after launch, a radar in the missile's nose, tuned to the fighter's radar signals, picks up the radiation reflected from the target and steers the missile to it.

Intended for use against bombers, air‐to‐air missiles were disappointing in combat against fighter aircraft. In the Vietnam War, the Sparrow had a probability of kill (PK) of only about 9 percent, while the Sidewinder had a PK of about 15 percent, both exceedingly low figures when one considers the time and money expended on them and the expectations they had evoked. Later variants offered more discriminating seekers and better reliability.

For many years the most sophisticated air‐to‐air missile in the world, the U.S. Navy's long‐range AIM‐54 Phoenix is used by the Northrop/Grumman F‐14 Tomcat and incorporates the Hughes AWG‐9 or AWG‐17 radar/fire control system. A large weapon weighing about 1,000 pounds, the Phoenix carries a 135‐pound warhead, and can reach a speed of Mach 5. The F‐14's Phoenix missile weapon system permits the tracking of up to twenty‐four targets and a choice of up to six simultaneous interceptions, over a range in excess of 125 miles.

Designed to replace the AIM‐7, the AIM‐120A Advanced Medium‐Range Air‐to‐Air Missile (AMRAAM) was developed jointly by the U.S. Air Force and the U.S. Navy, and entered service in 1992. Like the Phoenix, a “beyond visual range” (BVR) missile, it is intended for use on the F‐15, F‐16, F/A F‐18, and Tornado aircraft. The AIM‐120A is slightly smaller than the Sparrow, weighing only 345 pounds, and has a speed of about Mach 4, a range of 30 miles, with a 48‐pound warhead. The AIM‐120A has a high kill probability stemming from its being able to launch at any aircraft speed or target angle and from its “look‐down, shoot‐down” capability, meaning its ability to discern and hit a target against any background. Hughes Missile Systems and Raytheon are the principal contractors.

The Soviet Union, and its principal successor state, Russia, maintained a missile development program that closely matched that of the United States. The latest versions of the AA‐10 Alamo missile and the AA‐12 Adder have many of the characteristics of the AMRAAM. Other nations tend to create niche market air‐to‐air missiles tailored to their industrial capability and particular defense needs.

Air‐to‐Surface Missiles.

World War II saw the development of several air‐to‐surface tactical missiles, which ranged from the relatively simple 2.75‐inch‐diameter high‐velocity aerial rockets (HVAR) to forerunners of today's cruise missiles such as the Japanese Ohka kamikaze aircraft launched from Mitsubishi G4M “Betty” bombers.

The first major U.S. air‐to‐surface missile was the AGM‐12B Bullpup, developed for the U.S. Navy during the Korean War, but later adopted by the U.S. Air Force and many foreign air forces. The Bullpup was essentially a rocket‐propelled bomb guided by radio from the launch aircraft. Very inexpensive (at one point having a unit cost of only $5,000), the Bullpup was built by the tens of thousands and used by aircraft of many countries. It was continually improved over time, and a laser‐guided version was built for the U.S. Marine Corps.

First produced in 1971, the Hughes AGM‐65 Maverick represented a giant step forward technologically. The “launch and leave” Maverick depicts a target on a cockpit television screen; when launched, it homes automatically to its target. Later Mavericks had improved optics or an imaging‐infrared seeker. In the Gulf War, about 100 Mavericks a day were fired, about 90 percent by Fairchild A‐10 close air support aircraft.

The development of powerful Soviet defenses against air attack made air‐launched missiles attractive to the U.S. Air Force. The 30‐foot‐long, 13,000‐pound Bell XB‐63 Rascal was a supersonic missile attached like an enormous goiter to the side of Boeing DB‐47E carrier aircraft. After a troubled development, it entered service in October 1957. It was followed by the GAM‐72 Quail, a decoy missile intended to confuse enemy radar as to the strength and direction of attacking Boeing B‐52s.

Missiles soon acquired a strategic capability. The North American AGM‐28A Hound Dog was an impressive Mach 2.1 delta‐wing aircraft that would today be termed a cruise missile. It could fly at any altitude from tree‐top level to more than 50,000 feet, with a maximum range of 710 miles; later models carried terrain avoidance and electronic warfare equipment. The Hound Dog carried a thermonuclear warhead of up to 4 megatons, and would have been used to blast a way for the carrier aircraft to reach its targets. B‐52 G and H models could carry two Hound Dogs whose 7,500‐pound‐thrust Pratt & Whitney J52 engines could be used to augment takeoff power. Over 590 Hound Dogs were delivered to the Strategic Air Command, serving from 1961 to 1976.

Advances in computers and microcircuitry led to the development of the Boeing AGM‐69A SRAM (short‐range attack missile), only 14 feet long and weighing but 2,320 pounds. Eight SRAMs could be fitted into each of the rotary launchers installed in a B‐52 bomb bay. Additional SRAMs could be carried on the wing pylons formerly used for Hound Dog missiles, so that a B‐52 might carry as many as twenty missiles to cover a wide array of targets. The FB‐111 and B‐1 were also designed to accommodate SRAMs. The SRAM had a range of 35 to 105 miles, depending upon its launch altitude, at speeds up to Mach 3.5. The 170‐kiloton nuclear warhead made the SRAM a true force multiplier; but unexpected difficulties with propellant storage led to an earlier than planned removal from the fleet.

The SRAM was followed by a political football, the Air‐Launched Cruise Missile (ALCM). Originally designed as the AGM‐86 SCAD (Subsonic Cruise Armed Decoy) and intended as a more potent version of the Quail decoy, the missile was upgraded to ALCM status to be used as a bargaining chip in disarmament talks. President Jimmy Carter presented the ALCM as an inexpensive new idea that justified canceling the Rockwell B‐1 bomber.

The AGM‐86B ALCM is a small, unmanned, winged subsonic vehicle with an approximate speed of 500 mph and a range of 1,555 miles. The ALCM uses a terrain contour matching system (TERCOM) to update its inertial guidance system to achieve pinpoint navigational accuracy. B‐52s typically carry twelve ALCMs externally and eight more in the bomb bay. The longest combat mission in history took place when seven B‐52Gs took off from Barksdale Air Force Base, Louisiana, and opened the 17 January 1991 Desert Storm air offensive with a barrage of thirty‐five AGM‐86Cs with conventional high‐explosive warheads.

The most modern cruise missile in service is the AGM‐129 Advanced Cruise Missile, manufactured in the early 1990s by General Dynamics. The AGM‐129 has stealth characteristics coupled with a 2,000‐mile range and Mach .9 speed. A total procurement of 2,000 missiles was planned, but the breakup of the Soviet Union and some program delays resulted in termination of the program after 461 missiles were delivered.

The AGM‐84E‐1 standoff land‐attack missile (SLAM) is a derivative of the Harpoon (described below) and has similar physical characteristics and performance. It was created by combining the basic Harpoon with components of other systems, including the Maverick infrared seeker, a Global Positioning System, and a Walleye data link.

The former Soviet Union developed a parallel series of cruise and attack missiles, the most important of which was the AS‐15 “Kent.” The Kent corresponds to the ALCM and could be launched by air, land, or sea. It has an estimated range of 1,800 miles.

Antiradar Missiles.

The appearance of Soviet surface‐to‐air missiles forced the development of the first antiradar missile, the AGM‐45 Shrike. A development of the AIM‐7 Sparrow, the Shrike was first used in combat in 1966. With a Mach 2 speed and a range of up to 25 nautical miles, the Shrike weighs about 390 pounds, with a 145‐pound warhead. The Shrike is a joint product of Texas Instruments, Sperry‐Rand, and Univac.

The Shrike was succeeded first by the General Dynamics “Standard Arm,” the AGM‐78 Standard Antiradar Missile, which could continue homing in on the radar even after it had shut down. Like the Shrike, it was used in Vietnam and by the Israeli Air Force. Weighing 1,799 pounds, with a 215‐pound warhead, the AGM‐78 has a speed of Mach 2.5 and a maximum range of 30 nautical miles.

The current antiradar missile is the AGM‐88 High Speed Anti‐radiation Missile (HARM), developed jointly by the Naval Weapons Center at China Lake, California, and Texas Instruments. The Mach 2+ HARM has a much greater capability to lock on to enemy radar than its predecessors. It can be fired as a long‐range standoff missile, or its all‐aspect passive radar homing seeker can be used to detect and attack targets of opportunity. It demonstrated its prowess in the 1986 U.S. naval air strikes against Libya, and in the Gulf War, where more than 1,000 HARMs were fired. The AGM‐78 weighs about 800 pounds; its 145‐pound high‐explosive warhead is designed specifically for damaging radar antenna. The sophisticated British ALARM antiradar weapon also did well in the Gulf War.

Antiship Missiles.

The vulnerability of ships to missiles was first demonstrated in World War II, when a Luftwaffe Dornier Do 217 sank the Italian battleship Roma with two Fritz‐X missiles. In the 1982 Falklands War, Argentine Naval Air Force Super Entendard fighters launched Aerospatiale MM 38 Exocet missiles to sink the Royal Navy destroyer HMS Sheffield and the aviation supply ship HMS Atlantic Conveyor.

The principal U.S. antiship missile is the McDonnell‐Douglas AGM‐84 Harpoon, a long‐range, sea‐skimming “fire‐and‐forget” weapon manufactured in a variety of models. Its wings and control surfaces fold for storage, popping out after launch. About 13 feet long and weighing 1,170 pounds, the Harpoon is powered by a 600‐pound static‐thrust Teledyne Continental turbojet engine and cruises at Mach .85.

The Chinese have been especially active in building and selling antiship missiles like the HY‐4, designated “Silkworm” by NATO. While derivative of the early Soviet SS‐N‐2 “Styx,” the Silkworm's Mach 1.2 speed and 20‐mile range make it a formidable weapon. Other nations, including the former Soviet Union, France, Germany, Italy, Norway, and Sweden, have all developed specialized antishipping missiles, which have in turn led to the development of extraordinarily expensive defensive systems.

Airborne Antitank Guided Missiles.

Beginning with the World War II American “Bazooka” and the German Panzerfaust, antiarmor missiles became common, for they provide infantry with an inexpensive, flexible, and effective means to defeat opposing armor. The improvements in the guidance, propulsion, and warheads of antitank weapons have exceeded the ability of tank designers to defend against them.

The proliferation of antitank missiles can be traced to the French Nord SS‐10 guided missiles. Used by French helicopters in Algeria (the first combat role for helicopters), the SS‐10 has been called the “smallest, cheapest and most significant” missile since 1945 in that it expanded on German World War II practice and was exported to many foreign countries. A host of wire‐guided missiles followed, most line‐of‐sight missiles with manual control systems and an effective range of just over 1 mile. The second generation of weapons used computer technology to allow the gunner to “fly” the missile to the target by keeping it centered in his sights. The subsequent generation will be almost fully automatic, making full use of computers, television, fiber optics, guidance by lasers, and other technological advances.

The most important U.S. airborne antitank guided missile is the Rockwell International AGM‐114 Hellfire (the name deriving from “helicopter fire and forget”). Initially fielded as a laser‐guided weapon, the Hellfire accepts other guidance packages, including imaging‐infrared, radio frequency, and millimeter wavelength seekers.

The Hellfire is deployed on a wide variety of U.S. Army and Marine and Israeli Air Force helicopters. U.S. Army Bell “Apache” helicopters used it with effect in Operation Just Cause in Panama and in the Persian Gulf War. There it opened the war with a long‐distance raid on Iraqi early warning radar sites, scoring fifteen hits in two minutes. The Hellfire is a small, 100‐pound weapon with a wingspan of just over 1 foot, a speed of Mach 2.2, and a range of about 4 miles.

The first and most widely used U.S. antitank guided missile is the Hughes BGM‐71 TOW (tube‐launched, optically tracked, wired‐guided) weapon, which is fired from helicopters as well from a variety of ground installations. First used in Vietnam in May, 1972, the TOW had a sensational 80 percent hit record. With tens of thousands of TOWs in the field in armies around the world, the weapon has been used with effect in wars in Israel, Lebanon, Morocco, Iran, Pakistan, and Iraq. Weighing about 42 pounds, with a shaped, charged, high‐explosive armor‐piercing warhead, the TOW is effective at ranges up to about 3 miles. The TOW has been complemented by the formidable FIM‐92A Stinger, used by rebels with such devastating effect against the Soviet Union in Afghanistan, and adapt ed for current American helicopters. Hughes is the principal contractor but the vast quantities required called for a second source, Raytheon.

The Stinger is a “fire‐and‐forget” missile, weighing 22 pounds and with a speed of Mach 1. Designed for close‐in fighting, over ranges of less than 3 miles, the Stinger uses an all‐aspect automatic passive infrared homing device.

Helicopter warfare also requires an antiradar missile. The Motorola AGM‐122 Sidearm is essentially an AIM‐9C Sidewinder modified to have a broad band passive radar homing sensor. The missile is used primarily by the U.S. Marine Corps on both helicopters and fixed‐wing aircraft.

The role of the airborne missile can be expected to grow in the future; it waits in the wings as an antisatellite device, and will undoubtedly be employed in the next century by unmanned remote‐piloted vehicles in futuristic dogfights.
[See also Heat‐Seeking Technology; Marine Corps, U.S.: Since 1945; Panama, U.S. Military Involvement in; Weaponry.]

Bibliography

Bill Gunston , Rockets and Missiles, 1979.
Michael J. H. Taylor , Missiles of the World, 1980; 3rd ed. 1980.
Charles A. Sorrels , U.S. Cruise Missile Programs, 1983.
Kenneth P. Werrell , The Evolution of the Cruise Missile, 1985.
Lon O. Nordeen , Air Warfare in the Missile Age, 1985.
Christopher Chant , Compendium of Armaments and Military Hardware, 1987.
R. G. Lee, et al. , Guided Weapons, 1988.
Michael Del Papa , From SNARK to Peacekeeper, 1990.
Trevor N. Dupuy, editor in chief, International Military Defense Encyclopedia, Vol. 4, 1993.

Walter J. Boyne

Missiles

views updated May 14 2018

274. Missiles

See also 416. WEAPONRY .

ballistics
1. the science or study of the motion of projectiles.
2. the art or science of designing projectiles for maximum flight performance. ballistician , n. ballistic , adj.
ballistophobia
an abnormal fear of missiles.