The General Dynamics

General Dynamics

General Dynamics Corporation is a U.S. defense conglomerate formed by mergers and divestitures, and as of 2008 it is the fifth largest defense contractor in the world. Its headquarters are in West Falls Church , unincorporated Fairfax County, Virginia, in the Falls Church area.The company has...

 MIM-46 Mauler was a self-propelled anti-aircraft missile

Surface-to-air missile

A surface-to-air missile or ground-to-air missile is a missile designed to be launched from the ground to destroy aircraft or other missiles...

 system designed to a late 1950s US Army requirement for a system to combat low-flying high-performance tactical fighters and short-range ballistic missile

Ballistic missile

A ballistic missile is a missile that follows a sub-orbital ballistic flightpath with the objective of delivering one or more warheads to a predetermined target. The missile is only guided during the relatively brief initial powered phase of flight and its course is subsequently governed by the...

s. An advanced design for its era, the Mauler ran into intractable problems during development, and was eventually canceled in November 1965.

Mauler's cancellation left the US Army with no modern anti-aircraft weapon

Anti-aircraft warfare

NATO defines air defence as "all measures designed to nullify or reduce the effectiveness of hostile air action." They include ground and air based weapon systems, associated sensor systems, command and control arrangements and passive measures. It may be to protect naval, ground and air forces...

, and they rushed development of the much simpler MIM-72 Chaparral and M163 VADS

M163 VADS

The M163 Vulcan Air Defense System is a self-propelled anti-aircraft gun that was used by the United States Army. The M168 gun is a variant of the General Dynamics 20 mm M61 Vulcan rotary cannon, the standard cannon in most US combat aircraft since the 1960s, mounted on either an armored...

 to fill this niche. These weapons were much less capable than Mauler, and were intended solely as a stop-gap solution until more capable vehicles were developed. In spite of this, no real replacement entered service until the late 1990s. Both the US Navy and British Army

British Army

The British Army is the land warfare branch of Her Majesty's Armed Forces in the United Kingdom. It came into being with the unification of the Kingdom of England and Scotland into the Kingdom of Great Britain in 1707. The new British Army incorporated Regiments that had already existed in England...

 were also relying on Mauler for their own short-range needs and its cancellation left them with the same problem. They built the RIM-7 Sea Sparrow

RIM-7 Sea Sparrow

RIM-7 Sea Sparrow is a US ship-borne short-range anti-aircraft and anti-missile weapon system, primarily intended for defense against anti-ship missiles...

 and Rapier missile

Rapier missile

Rapier is a British surface-to-air missile developed for the British Army and Royal Air Force. Entering service in 1971, it eventually replaced all other anti-aircraft weapons in Army service; guns for low-altitude targets, and the English Electric Thunderbird, used against longer-range and...

, respectively, to fill these needs.

Duster and Vigilante

The US Army's first custom-designed anti-aircraft weapon was the M42 Duster

M42 Duster

The M42 40 mm Self-Propelled Anti-Aircraft Gun, or "Duster," is an armored light air-defense gun built for the U.S. Army from 1952 until December 1959. Production of this vehicle was performed by the tank division of the General Motors Corporation. It used components from the M41 light tank...

, mounting two Bofors 40 mm gun

Bofors 40 mm gun

The Bofors 40 mm gun is an anti-aircraft autocannon designed by the Swedish defence firm of Bofors Defence...

s in an optically-aimed turret on a M41 Walker Bulldog

M41 Walker Bulldog

The M41 Walker Bulldog was a U.S. light tank developed to replace the M24 Chaffee. It was named for General Walton Walker who died in a jeep accident in Korea...

 light tank

Light tank

A light tank is a tank variant initially designed for rapid movement, and now primarily employed in low-intensity conflict. Early light tanks were generally armed and armored similar to an armored car, but used tracks in order to provide better cross-country mobility.The light tank was a major...

 chassis. First entering production in 1952, the Duster quickly became outdated as aircraft performance increased.

To replace the Duster, the Army started work on the Sperry Vigilante

T249 Vigilante

The T249 Vigilante was a prototype 37 mm self-propelled anti-aircraft gun designed as a replacement for the Bofors 40 mm gun and M42 Duster in US Army service. The system consisted of a 37 mm T250 six-barrel Gatling gun mounted on a lengthened M113 armored personnel carrier platform...

, which mounted a powerful 37 mm Gatling gun

Gatling gun

The Gatling gun is one of the best known early rapid-fire weapons and a forerunner of the modern machine gun. It is well known for its use by the Union forces during the American Civil War in the 1860s, which was the first time it was employed in combat...

 on top of a modified M113 Armored Personnel Carrier

M113 Armored Personnel Carrier

The M113 is a fully tracked armored personnel carrier that has formed the backbone of the United States Army's mechanized infantry units from the time of its first fielding in Vietnam in April 1962. The M113 was the most widely used armored vehicle of the U.S...

 chassis. Although the Vigilante was, like the Duster, optically aimed and guided, its 3,000 rpm firing rate gave it much better performance against high-speed aircraft.

As the Vigilante program continued, the Army decided that any gun-based system was hopeless as speeds increased and engagement times dropped. The Vigilante had a maximum effective range of about 3000 yards (2,743.2 m), and its shells took about 5 seconds to cross this distance. A jet aircraft flying at 500 mph (223.5 m/s) would cover over a kilometer during those 5 seconds. By the time a radar-assisted sighting system could develop a firing solution, the target would be out of range.

Given their doubts in the new system, the Army decided to cancel the Vigilante and keep the Duster in service until a much more capable all-missile system arrived to replace it.

FAAD

Under the "Forward Area Air Defense" (FAAD) project, the Army began collecting theoretical data on the requirements for a missile-based system in 1959.

Guidance was a major area of concern. Most anti-aircraft missiles of the era use semi-active radar homing

Semi-active radar homing

Semi-active radar homing, or SARH, is a common type of missile guidance system, perhaps the most common type for longer-range air-to-air and surface-to-air missile systems. The name refers to the fact that the missile itself is only a passive detector of a radar signal – provided by an external ...

 (SARH), with an "illumination radar" reflecting signals off the target that were picked up by a small receiver in the missile's nose. This system had the advantage that the radar signal continued to grow in strength as the missile approached the target, making it increasingly easy to track. More importantly, the reflected signal was a cone shape centered on the target, so as the missile approached it the guidance became increasingly accurate.

On the downside, the SARH concept also meant that any other reflections could confuse the missile's seeker. Since SARH relied on making the seeker in the missile as simple as possible in order to fit into the missile body, it was common for seekers of the area to be easily confused by reflections from trees, buildings or the ground. It was difficult for the missile to distinguish the target in a cluttered environment.

For FAAD, they decided to use a beam riding

Beam riding

Beam-riding, also known as beam guidance, is a technique of directing a missile to its target by means of radar or a laser beam. The name refers to the way the missile flies down the guidance beam, which is aimed at the target...

 guidance system

Guidance system

A guidance system is a device or group of devices used to navigate a ship, aircraft, missile, rocket, satellite, or other craft. Typically, this refers to a system that navigates without direct or continuous human control...

. These had been used in early missiles like the Nike Ajax and SA-2 Guideline, but had been abandoned in favor of semi-active systems for all of the reasons above. In particular, in the case of beam-riding the signal is shaped like a cone centered on the broadcaster, which means it becomes increasingly inaccurate as the missile flies towards the target. Some sort of secondary terminal guidance system was almost always needed with beam-riding weapons.

In spite of these disadvantages, beam-riding offered FAAD the ability to guide the missiles in close proximity to the ground. Since the guidance signal is received at the rear of the missile body, the signal would remain clear as long as there were no obstructions between the missile and launcher. It was only the launch platform

Transporter erector launcher

A transporter erector launcher is a vehicle with an integrated prime mover that can carry, elevate to firing position and launch one or more missiles. Such vehicles exist for both surface-to-air missiles and surface-to-surface missiles...

 that had to have the ability to distinguish targets from ground clutter, which was easier to do with a larger workspace and more power. FAAD used a continuous wave radar, which uses the Doppler shift of the moving targets to locate them against any sort of background. For terminal guidance, FAAD used an advanced infrared homing

Infrared homing

Infrared homing refers to a passive missile guidance system which uses the emission from a target of electromagnetic radiation in the infrared part of the spectrum to track and follow it. Missiles which use infrared seeking are often referred to as "heat-seekers", since infrared is just below the...

 system.

Given the quick engagement times, on the order of seconds, the Army decided that FAAD had to have semi-automatic actions. In combat, the operators would select targets on a long-range search radar and then simply say "go" to attack them. The system's fire control computer

Fire-control system

A fire-control system is a number of components working together, usually a gun data computer, a director, and radar, which is designed to assist a weapon system in hitting its target. It performs the same task as a human gunner firing a weapon, but attempts to do so faster and more...

 would slew the weapons and fire automatically as soon as they came in range.

After running Monte Carlo simulations

Monte Carlo method

Monte Carlo methods are a class of computational algorithms that rely on repeated random sampling to compute their results. Monte Carlo methods are often used in computer simulations of physical and mathematical systems...

 on a IBM 650

IBM 650

The IBM 650 was one of IBM’s early computers, and the world’s first mass-produced computer. It was announced in 1953, and over 2000 systems were produced between the first shipment in 1954 and its final manufacture in 1962...

, they decided to use a blast-fragmentation warhead, deciding that the continuous-rod warhead

Continuous-rod warhead

A continuous-rod warhead is a specialized munition that exhibits an annular blast fragmentation pattern. It is used in anti-aircraft and anti-missile missiles.-Early anti-aircraft munitions:...

 would be less effective.

For mobility, the system would be based on the M113, the Army's latest APC and one of the more advanced vehicles in the inventory. The modifications needed to support a missile system were relatively simple, and the crew area inside the chassis offered room for the needed equipment. The resulting vehicle was known as the XM-546.

Development

Several companies responded to the FAAD contract tender, which General Dynamics (Convair Pomona Division) won in 1959. In 1960 the project was given the official name "Mauler".

The Army was not the only potential user of the Mauler system; both the British Army

British Army

The British Army is the land warfare branch of Her Majesty's Armed Forces in the United Kingdom. It came into being with the unification of the Kingdom of England and Scotland into the Kingdom of Great Britain in 1707. The new British Army incorporated Regiments that had already existed in England...

 and US Navy planned on using Mauler for their own needs. The British Army's intended role was essentially identical to the US's, but the Navy was looking for a solution to the problem of air attack against their capital ship

Capital ship

The capital ships of a navy are its most important warships; they generally possess the heaviest firepower and armor and are traditionally much larger than other naval vessels...

s both by high-speed aircraft as well as early (non-skimming) anti-shipping missiles. Starting in 1960 they had developed a program for a "Basic Point Defense Missile System" (BPDMS), and intended to use a modified version of the Mauler, the "RIM-46A Sea Mauler", to fill this role. Mauler's beam riding system made it preferable to other missile systems because it would have less problems with clutter from the sea. Additionally, its fast-acting semi-automatic fire control was highly desired for a weapon that was expected to counter targets with engagement times under a minute. Expecting its arrival, the Navy's latest destroyer escort

Destroyer escort

A destroyer escort is the classification for a smaller, lightly armed warship designed to be used to escort convoys of merchant marine ships, primarily of the United States Merchant Marine in World War II. It is employed primarily for anti-submarine warfare, but also provides some protection...

s, the Knox class frigate

Knox class frigate

Knox class frigates were United States Navy warships, originally laid down as ocean escorts , but were all redesignated as frigates on 30 June 1975 in the USN 1975 ship reclassification and their hull designation changed from DE to FF.A sub-class of the Knox class was built, commonly referred to as...

, were built with space reserved for the Sea Mauler launchers when they arrived.

Development of the missile airframe and engine progressed rapidly. Unguided examples, known as "Launch Test Vehicles", started firing tests in September 1961. These were quickly followed by the "Control Test Vehicle" (CTV) guided examples in 1961, which flew simple paths to test the aerodynamic controls. Both test series demonstrated a variety of problems, including failures of the rocket casings, and excessive drag and wing flutter.

The first "Guidance Test Vehicle" (GTV), essentially the service prototypes, started firing in June 1963. These also demonstrated an array of problems, most worrying was the continued tendency to lose guidance instructions immediately after launch. Additionally, when mounted in the 3 by 3 box launcher, the missiles would break their containers and damage the missiles in adjacent containers. Eventually no less than 22 different container materials would be used in an attempt to find a suitable solution.

Cancellation

By this point there were serious doubts that the system would be entering service any time soon. On 16 September 1963 the Army Materiel Command

United States Army Materiel Command

The U.S. Army Materiel Command is the primary provider of materiel to the United States Army.The Command's mission includes the research & development of weapons systems as well as maintenance and parts distribution....

 asked the Aviation and Missile Command

United States Army Aviation and Missile Command

The United States Army Aviation and Missile Command is primarily responsible for life cycle management of army missile, helicopter, unmanned ground vehicle and unmanned aerial vehicle weapon systems. The central part of AMCOM's job involves acquisition and sustainment support for aviation and...

 to study adapting the Navy's AIM-9 Sidewinder

AIM-9 Sidewinder

The AIM-9 Sidewinder is a heat-seeking, short-range, air-to-air missile carried mostly by fighter aircraft and recently, certain gunship helicopters. The missile entered service with United States Air Force in the early 1950s, and variants and upgrades remain in active service with many air forces...

 missile as the basis of a short-range anti-aircraft system. They suggested that the conversion would be simple, but the missile's long lock-on

Missile lock-on

Missile lock-on refers to a scenario where the guidance system for a missile can accurately track a target, and a fire-control system can calculate the required flightpath for the missile to hit the target...

 time and optical guidance would make it ineffective in close combat.

Based on this potential solution to the air defense problem, the Army Staff, supported by the Army Air Defense Artillery School at Fort Bliss, started a new study under the direction of Lieutenant Colonel

Lieutenant colonel

Lieutenant colonel is a rank of commissioned officer in the armies and most marine forces and some air forces of the world, typically ranking above a major and below a colonel. The rank of lieutenant colonel is often shortened to simply "colonel" in conversation and in unofficial correspondence...

 Edward Hirsch. Known as the "Interim Field Army Air Defense Study" (IFAADS), it called for a multi-layer system consisting of an adapted Sidewinder as a missile component known as the MIM-72 Chaparral, a short-range gun component using the M61 Vulcan

M61 Vulcan

The M61 Vulcan is a hydraulically or pneumatically driven, six-barreled, air-cooled, electrically fired Gatling-style rotary cannon which fires 20 mm rounds at an extremely high rate. The M61 and its derivatives have been the principal cannon armament of United States military fixed-wing aircraft...

 known as the M163 VADS

M163 VADS

The M163 Vulcan Air Defense System is a self-propelled anti-aircraft gun that was used by the United States Army. The M168 gun is a variant of the General Dynamics 20 mm M61 Vulcan rotary cannon, the standard cannon in most US combat aircraft since the 1960s, mounted on either an armored...

, and the separate AN/MPQ-49 Forward Area Alerting Radar

AN/MPQ-49 Forward Area Alerting Radar

The AN/MPQ-49 Forward Area Alerting Radar is a lightweight early warning radar system consisting of the AN/TPQ-43 radar, AN/TPX-50 Mark XII IFF receiver, a 5 kW generator set, and a Gama Goat providing mobility.-Development:...

 that would support both by sending digital information to displays in those platforms. All of these would be further supported by the FIM-43 Redeye

FIM-43 Redeye

The General Dynamics FIM-43 Redeye was a man-portable surface-to-air missile system. It used infrared homing to track its target. Production was terminated in September 1969 after about 85,000 rounds had been built - in anticipation of the Redeye II, which later became the FIM-92 Stinger...

 man-portable missile. Although the resulting composite system would not be nearly as capable as Mauler, it could be in service much sooner and provide some cover while a more capable system developed.

In November 1963 Mauler was re-directed as a pure technology demonstration program. Several modified versions using simpler systems were proposed, but even these would not have entered service before 1969. Tests with the GTV's continued until the entire program was cancelled outright in November 1965. Chaparral adapted the Mauler's IR seeker, which was greatly improved over the versions in the original AIM-9C.

Aftermath

The Chaparral/Vulcan combination was always intended to be a stop-gap solution while a more powerful system evolved. However, in the 1970s the threat was perceived to change from tactical aircraft to missile-firing helicopters that would "pop-up" from behind cover. This suggested the use of a fast-acting gun system, albeit one with much longer range than the Vulcan's 1,200 m. Out of these studies came the "Division Air Defense" concept that was eventually filled by the M247 Sergeant York

M247 Sergeant York

The M247 Sergeant York DIVAD was a self-propelled anti-aircraft weapon , developed by Ford Aerospace in the late 1970s. Based on the M48 Patton tank, it replaced the Patton's turret with a new one that featured twin radar-directed 40 mm rapid-fire guns...

. This program ran into serious technical problems of its own, and was eventually cancelled in 1985.

After the Sergeant York was cancelled, the Army joined forces with the Canadian Forces

Canadian Forces

The Canadian Forces , officially the Canadian Armed Forces , are the unified armed forces of Canada, as constituted by the National Defence Act, which states: "The Canadian Forces are the armed forces of Her Majesty raised by Canada and consist of one Service called the Canadian Armed Forces."...

 to develop a new system. The result was the Oerlikon Contraves

Oerlikon Contraves

Rheinmetall Air Defence AG is a division of German armament manufacturer Rheinmetall, created when the company's Oerlikon Contraves unit was renamed on 1 January 2009 and integrated with Rheinmetall's other air-defence products...

-designed built-in-Canada ADATS

Air Defense Anti-Tank System

The Air Defense Anti-Tank System is a dual-purpose short range surface-to-air and anti-tank missile system based on the M113A2 vehicle. It is manufactured by the Swiss company Oerlikon-Contraves, a member of the Rheinmetall Defence Group of Germany....

, which is extremely similar to the original Mauler in form, function and even the launch platform, an adapted M113. ADATS is somewhat more capable than Mauler, however, with ranges up to 10 km and higher speeds. However, the ending of the Cold War

Cold War

The Cold War was the continuing state from roughly 1946 to 1991 of political conflict, military tension, proxy wars, and economic competition between the Communist World—primarily the Soviet Union and its satellite states and allies—and the powers of the Western world, primarily the United States...

 led the Army to cancel their ADATS purchase, leaving Chaparral/Vulcan in service even longer. The anti-aircraft role was eventually filled by the Bradley Linebacker, based on the short-range FIM-92 Stinger

FIM-92 Stinger

The FIM-92 Stinger is a personal portable infrared homing surface-to-air missile , which can be adapted to fire from ground vehicles and helicopters , developed in the United States and entered into service in 1981. Used by the militaries of the U.S...

.

The cancellation also left the British Army without a defense system, but they had prepared for this eventuality, having had several US missile systems cancelled out from under them in the past. Before selecting the Mauler, the British Aircraft Corporation

British Aircraft Corporation

The British Aircraft Corporation was a British aircraft manufacturer formed from the government-pressured merger of English Electric Aviation Ltd., Vickers-Armstrongs , the Bristol Aeroplane Company and Hunting Aircraft in 1960. Bristol, English Electric and Vickers became "parents" of BAC with...

 had been working on a private project known as "Sightline", and continued its development as a low priority while the Mauler program progressed. On its cancellation, Sightline was given full development funds, and entered service in 1971 as Rapier

Rapier missile

Rapier is a British surface-to-air missile developed for the British Army and Royal Air Force. Entering service in 1971, it eventually replaced all other anti-aircraft weapons in Army service; guns for low-altitude targets, and the English Electric Thunderbird, used against longer-range and...

.

The US Navy was in a somewhat more troubling position. In addition to their need to replace guns and existing missile systems like the RIM-24 Tartar

RIM-24 Tartar

The General Dynamics RIM-24 Tartar was a medium-range naval surface-to-air missile , and was among the earliest surface-to-air missiles to equip United States Navy ships...

, they were also looking to replace short-range gun systems on their older ships. Mauler was "built-in" not only to their latest ship designs, like the Knox, but formed the basis for their entire anti-aircraft concept for the 1970s. It was believed that Mauler would greatly improve the capabilities of smaller ships, allowing them to take on some of the roles that would normally require a much larger platform, like a full destroyer.

With Mauler's cancellation, the Navy had to start a crash program to develop a suitable system. As the infrared-guided Sidewinder would be of limited use against aircraft or missiles approaching head-on, they were forced to use the AIM-7 Sparrow

AIM-7 Sparrow

The AIM-7 Sparrow is an American, medium-range semi-active radar homing air-to-air missile operated by the United States Air Force, United States Navy and United States Marine Corps, as well as various allied air forces and navies. Sparrow and its derivatives were the West's principal beyond visual...

 instead. Although the Sparrow was a capable missile, it was intended for launch from high-speed aircraft and thus had relatively low acceleration, trading this for longer cruising time and range. An entirely new motor was developed for the new "Sea Sparrow". To guide it, a new manually-controlled radar illuminator was developed, guided by an aimer standing between two large radar dishes that looked somewhat like searchlight

Searchlight

A searchlight is an apparatus that combines a bright light source with some form of curved reflector or other optics to project a powerful beam of light of approximately parallel rays in a particular direction, usually constructed so that it can be swiveled about.-Military use:The Royal Navy used...

s. The ship's search radars would send target information via voice channels to the operator, who would slew the illuminators onto the target and launch the missiles. The missiles were held in a large eight-cell rotating launcher than was slaved to the illuminator in order to allow the seeker to see the reflected signal. The system, as a whole, was much larger than Mauler, had shorter range, and much longer reaction times.

In spite of the Sea Sparrow's relative simplicity, it was quickly upgraded. The use of folding mid-mounted wings allowed the launcher cells to be greatly reduced in size, and an automatic tracking system was soon added to the radar illuminator system. This was again upgraded to allow the phased-array radars of modern ships to guide the Sparrow directly, removing the need for the relatively large illuminators. The evolution continued with the latest models, which can be vertically launched from four-cell containers, greatly expanding the number that can be carried on most ships. What started as a quick-and-dirty solution to the hole left by the Mauler evolved into a system of even greater capability.

Description

The General Dynamics Mauler system used a large A-frame

A-Frame

An A-frame is a basic structure designed to bear a load in a lightweight economical manner. The simplest form of an A-frame is two similarly sized beams, arranged in a 45-degree or greater angle, attached at the top...

 mounted on the top of the vehicle that contained a phased array

Phased array

In wave theory, a phased array is an array of antennas in which the relative phases of the respective signals feeding the antennas are varied in such a way that the effective radiation pattern of the array is reinforced in a desired direction and suppressed in undesired directions.An antenna array...

 continuous wave search radar at the top, the smaller tracking/illumination radar on one side, and a large box containing nine missiles between the "legs". The entire system was mounted at the back of the XM546 "Tracked Fire Unit" on a rotating platform that allowed the missiles to be pointed toward the target. Before launch the protective cover over the missile's canister was popped off to allow the infrared seeker to see the target, and then it was launched into the illuminating radar's beam.

Raytheon provided both the search and illumination radars, while Burroughs provided the fire control system. The missile itself was 6 feet (1.8 m) long, 5 inches (12.7 cm) in diameter, had a 13 inches (33 cm) fin span, and weighed 120 pounds (54.4 kg). It had a maximum range of 5 miles (8 km) and ceiling of 20000 feet (6,096 m), powered by a Lockheed solid-fuel motor of 8350 pound-forces (37,142.7 N).