M247 Sergeant York
Encyclopedia
The M247 Sergeant York DIVAD (Division Air Defense) was a self-propelled anti-aircraft weapon
(SPAAG), 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. The vehicle was named after Sergeant Alvin York
, a famous World War I
hero.
The Sergeant York was intended to fight alongside the M1 Abrams
and M2 Bradley
fighting vehicles in the U.S. Army, in a role similar to the Soviet ZSU-23-4
and German Gepard
. It would replace the M163 Vulcan Air Defense System
and MIM-72 Chaparral, ad-hoc systems of limited performance that had been introduced when the more advanced MIM-46 Mauler
failed to mature.
Despite the use of many off the shelf
technologies that were intended to allow rapid and low-cost development, a series of technical problems and massive cost overruns resulted in the cancellation of the project in 1985.
when its replacement never arrived.
The first proposed replacement for the Duster was the Sperry Vigilante
, which referred to the six-barreled 37 mm Gatling gun
proposed as the basis for a new SPAAG. Although the gun was extremely powerful, at some point in the late 1950s the Army decided that all gun-based systems were out of date.
The next proposed replacement for the Duster was the ambitious MIM-46 Mauler
. Mauler mounted a nine-missile magazine on top of an adapted M113 Armored Personnel Carrier
chassis, along with detection and tracking radars. Mauler featured a completely automatic fire control system, with the operators simply selecting targets and pressing "OK". It would be able to respond to low-flying high-speed targets at any angle out to a range of about five miles. However, Mauler proved to be beyond the state-of-the-art and ran into intractable problems during development. Realizing it was not going to enter service any time soon, it was downgraded to a technology demonstration program in 1963, and eventually cancelled outright in 1965.
Still lacking an effective anti-aircraft system, the Army started development of two stop-gap systems that were meant to operate in concert. The M163 VADS
combined the M61 Vulcan
cannon, the M113 chassis, and an all-optical fire control system with a simple lead-computing gunsight. Suitable for "snap shots" against nearby targets, the VADS system was equipped only with a small ranging radar for the gunsight, its firing range being too small to justify a larger tracking radar. VADS was intended to operate in concert with the MIM-72 Chaparral, which combined the AIM-9 Sidewinder
missile with a more heavily modified version of the M113 chassis. The Chaparral's AIM-9D missiles were capable of tail-chase launches only, but offered ranges up to 5 miles. Also using an all-optical firing system, the Chaparral nevertheless required the operator to "settle" the missiles on the target for a period of time to allow them to lock on, limiting its ability to deal with quickly moving targets. Both vehicles were optionally supported by the AN/MPQ-49 Forward Area Alerting Radar
(FAAR), but this system was towed by the Gama Goat
and could not be used near the front line
s. The pair of weapons was, at best, a nuisance to the enemy and had limited performance against modern aircraft.
At one point the Army started to become concerned about developments in sensor technologies that would allow attacks by fixed-wing aircraft at night or in bad weather. They developed a requirement for a weapon system able to operate using FLIR and a laser rangefinder in order to counter these threats. However, the rest of the military establishment disapproved of the idea; even the US Air Force was able to carry out only limited operations in bad weather, and the Soviets had a considerably less capable force in this regard. The idea gained little traction and died.
anti-tank missiles improved to the point where they became a major threat to armored operations. The U.S. led the field with their TOW missile
on the Cobra gunship
, demonstrating this powerful combination in combat in 1972's Easter Offensive. The Soviets initially lagged the U.S., but the introduction of the 9K114 Shturm missile on the Mil Mi-24
in the 1970s offered the USSR a level of parity.
Unlike fixed-wing aircraft, attack helicopters had the ability to loiter near the front behind cover and pick their targets. They would then "pop up", launch a missile, and return to cover as soon as the missile hit its target. Using fast-reacting wire-guided
or radio-command missiles meant the total engagement time was kept to a minimum, as there was little or no "lock-on" time required; the operator simply fired and adjusted the missile's flight path onto the target while it flew. Against these targets, the Vulcan/Chaparral combination was effectively useless. The Vulcan could react quickly enough to the fleeting targets, but its 20 mm gun had an effective range of only about 1,200 meters, far shorter than the 3,000 to 5,000 meters range of the "Spiral". While the Chaparral had enough range to engage the "Hind", its lengthy lock-on period meant the Hind would have hit its target and hidden behind terrain again before the Sidewinder would reach it. Additionally, the older Sidewinder missiles used on Chaparral homed in on exhaust, and had very limited capability against helicopters faced head-on.
The limited effectiveness of the Vulcan/Chaparral was not the only problem the US Army was facing in the late 1970s. At the time they were also in the process of introducing the new M1 Abrams
and M2 Bradley
vehicles, which had dramatically improved cross-country performance. The M113-based Vulcan and Chaparral could not keep up with them on the advance, and would leave them open to attack in a fast moving front.
Finally, the Soviets were widely introducing the ZSU-23-4
"Shilka", which was cause for some concern after it appeared in the Middle East. Israeli pilots attempting to avoid fire from Syrian SA-6 batteries would fly low, directly into the Shilka's envelope. Several aircraft were lost or damaged.
At the time, most U.S. military policy was based on the US Air Force quickly gaining air superiority and holding it throughout a conflict. In keeping with this, the Army had previously placed relatively low priority on anti-aircraft weapons. This gave them time to mature through testing and shakedowns. In the case of DIVADs the threat was considered so serious and rapidly developing that the Army decided to skip the traditional development period and try to go straight into production by using a number of "off-the-shelf" parts. Colonel Russell Parker testified before the Senate Armed Services Committee in March 1977 that "We expect this somewhat unorthodox approach to permit a much reduced development time, thus resulting in an earliest fielding date, albeit with higher but acceptable risks... the manufacturer will be required by the fixed price warranty provisions, to correct deficiencies." It was claimed that this would cut up to five years from the development cycle, although it would require problems to be found and fixed on the operational vehicles.
Colonel Parker unveiled the DIVAD plan to 49 industry representatives on 18 May 1977. The DIVADs requirement demanded that the entrants be based on the M48 Patton
tank chassis, provided by the Army, which were held in large quantities in surplus depots. DIVAD called for the gun to acquire a target and start firing within five seconds (later extended to eight) of it becoming visible or coming into its 3,000 m range, and had to have a 50% chance of hitting a target with a 30 round burst. In addition to all-weather capability, it also needed to have optical aiming capabilities, including a FLIR and laser rangefinder.
Sperry Rand entered a system based on their older Vigilante gun, modified to fire the 35 mm round from the Oerlikon KDA
series, widely used in NATO in the anti-aircraft role. The gun could be fired at 3,000 rounds per minute for anti-aircraft use, or 180 rounds per minute for use against ground targets, fed from a 1,464 round magazine. The aluminium turret was topped by two radars and an IFF
system, all from Sperry.
General Electric
entered a version with a small turret mounting their 30 mm GAU-8 Avenger
cannon from the A-10 Thunderbolt II
. It included a single search/track radar adapted from the earlier FAAR, although they later suggested an improved system.
Raytheon
proposed using the turret from the Dutch version of the German Gepard flakpanzer
. Most of the turret remained the same as the original Gepard, including the twin 35 mm Oerlikon KDA cannons, but used Hollandse Signaalapparaten
radars and an Oerlikon Contraves
fire-control computer. Raytheon demonstrated that the turret, although designed for the Leopard 1, could be mounted on the M48 with some adaptation.
General Dynamics
' entry also mounted twin Oerlikon KDA cannons, but mounted them side-by-side in a new aluminum turret, as opposed to either side of the turret as in the Gepard. They could be fired in either the automatic or semiautomatic mode, and their combined rate of fire was 1,100 rounds per minute from a 600 round magazine. The radar and fire control systems were derived from their Phalanx CIWS
system, with the tracking radar mounted on the front of the turret, beside the guns, and the search radar on top. The turret also included independently stabilized optical sights and a laser range finder for manual engagements.
Ford Aerospace
's entry was based around the Bofors 40 mm L/70 cannons, twin-mounted in the center of the turret in a fashion similar to the General Dynamics entry. The relatively large and boxy turret also mounted separate long-range search and short-range tracking radars on top. The radars were mounted on booms to give them a clear view of the sky, and both had the ability to be folded down to reduce the vehicle's height during travel. The tracking radar was a modified version of the Westinghouse AN/APG-66 from the F-16 Fighting Falcon
. Like the GD entry, it also mounted a complete optical sighting and ranging system.
Some critics claim that Ford's use of the 40 mm Bofors appears to have been a business decision, not a technical one. While the 35 mm round was already a widely accepted NATO standard and was technically well respected, Ford had a marketing agreement with Bofors
. As Gregg Easterbrook
later reported:
However, the Bofors 40 mm cannon also had worldwide popularity. In addition, FACC had developed a proximity-sensing round for the 40 mm, which increased probability of a kill, and the shell carried either a greater explosive charge or higher deadweight mass than the smaller anti-aircraft platforms. These factors would be important in the primary scenario for which the DIVAD was to be deployed, that being the large-theater land operations vs the Warsaw Pact
.
in June 1980. On schedule, both companies delivered their prototypes to the North McGregor Test Facility and head-to-head testing began. The shoot-off was delayed for two months "because the prototypes which arrived at Fort Bliss test range were too technically immature." In the DT/OT II test series they shot down two F-86 Sabre
fighters, five UH-1 Huey helicopters and twenty-one smaller drones.
After the 29-month Phase One trial, Ford's entry was selected as the winner of the DIVADs contest on 7 May 1981, and given a fixed-price $6.97 billion development and initial production contract for deliveries at various rates. The system was officially named M247 Sergeant York when the contract was awarded. The decision was controversial, as the GD entry had "outscored" the Ford design consistently in testing, nineteen "kills" to nine by most accounts.
Ford's prototype vehicle started demonstrating problems almost immediately. The main concerns had to do with the tracking radar, which demonstrated considerable problems with ground clutter. In testing, it was unable to distinguish between helicopters and trees. When the guns were pointed upward to fire on high-angle targets, the barrels projected into the radar's line of sight and further confused the system. Additionally, the reaction time was far too slow; against hovering helicopters it was 10 to 11 seconds, but against high-speed targets it was from 11 to 19, far too long to take a shot.
The RAM-D (reliability, availability, maintainability and durability) tests ran from November 1981 to February 1982, demonstrating a wide range of operation concerns. The turret proved to have too slow a traverse to track fast moving targets, and had serious problems operating in cold weather, including numerous hydraulic leaks. The simple electronic counter-countermeasures
(ECCM) suite could be defeated by only minor jamming. The used guns taken from U.S. Army stock were in twisted condition due to careless warehousing. Perhaps the most surprising problem was that the 30-year-old M48 chassis with the new 20-ton turret meant the vehicle had trouble keeping pace with the newer M1 and M2, the vehicles it was meant to protect.
In February 1982 the prototype was demonstrated for a group of US and British officers at Fort Bliss, along with members of Congress and other VIPs. When the computer was activated, it immediately started aiming the guns at the review stands, causing several minor injuries as members of the group jumped for cover. Technicians worked on the problem, and the system was restarted. This time it started shooting towards the target, but fired into the ground 300 m in front of the tank. In spite of several attempts to get it working properly, the vehicle never successfully engaged the sample targets. A Ford manager claimed that the problems were due to the vehicle being washed for the demonstration and fouling the electronics. In a report on the test, Easterbrook jokingly wondered if it ever rained in central Europe.
As early production examples started rolling off the production line, the problems proved to be just as serious. One of the early models is reported to have locked onto a latrine fan, mistaking its return for a moving target of low-priority. Reporting on the incident in another article on the vehicle's woes, Easterbrook reported that "During a test one DIVAD locked on to a latrine fan. Michael Duffy, a reporter for the industry publication Defense Week, who broke this aspect of the story, received a conference call in which Ford officials asked him to describe the target as a 'building fan' or 'exhaust fan' instead."
Nevertheless, the program's manager within the Army was cautiously positive. Major General Maloney said, "The DIVAD battery-eight systems plus one spare-activated 1 November 1984, at Fort Bliss to prepare for tests, has been demonstrating 90% reliability for full systems capability. The systems have been able to operate in a degraded manner a further 2% of the time and have had an 8% inoperable rate." He later stated that the “gun still had problems with software and electronic countermeasures, but my sensing was that it was certainly no worse than many weapon systems at this period in their gestation.”
to the DIVAD system, leading to even more cries about its ineffectiveness.
As Washington became increasingly fed up with the DIVAD's problems, Secretary of Defense Caspar Weinberger
ordered a $54 million series of battlefield-condition tests. Congress authorized production money to keep the program alive through a test-fix-test cycle but with a caveat; the funds would be released only if Weinberger certified that the gun "meets or exceeds the performance specifications of its contract." The tests were monitored by the Pentagon's new Operational Test and Evaluation Office (OT&E), mandated by Congress in 1983 to serve as an independent watchdog. The tests were carried out late in 1984.
The results were abysmal. Unable to hit drones moving even in a straight line, the tests were later relaxed to hovering ones. The radar proved unable to lock even to this target, as the return was too small. The testers then started adding radar reflectors to the drone to address this "problem", eventually having to add four. Easterbrook, still covering the ongoing debacle, described this as being similar to demonstrating the abilities of a bloodhound
by having it find a man standing alone in the middle of an empty parking lot, covered with steaks. The system now tracked the drone, and after firing a lengthy burst of shells the drone was knocked off target. As it flew out of control, the range safety officer had it destroyed by remote control. This was interpreted by the press as an attempt to "fake" the results, describing it as "sophomoric deceits". From that point on, every test success was written off as faked.
The OT&E concluded that the gun could perform the mission as originally specified, but the tests also showed that the system had considerable reliability problems, many as the result of trying to adapt a radar system developed for aircraft to the ground role. Initial production tests run from December 1984 to May 1985 turned up a continued variety of problems, failing 22 of 163 contract requirements, and 22 serious failures in operational readiness. Contrary to the Army's earlier reports, OT&E Director Jack Krings said the tests showed, "the SGT YORK was not operationally effective in adequately protecting friendly forces during simulated combat, even though its inherent capabilities provided improvement over the current [General Electric] Vulcan gun system. The SGT YORK was not operationally suitable because of its low availability during the tests." They measured the availability of the system at 33%, as opposed to the required 90%.
On 27 August 1985, Secretary of Defense Caspar Weinberger
killed the project after about 50 vehicles had been produced. He said, "the tests demonstrated that while there are marginal improvements that can be made in the York gun, they are not worth the additional cost-so we will not invest any more funds in the system." Noting that cancelling the project did not imply a lack of need, he started the process of studying a missile-based system to fill the same niche. This led to the Oerlikon Canada ADATS
system, which suffered problems of its own and entered service only in the Canadian Army
. The niche was eventually filled by the M6 Linebacker, an adaptation of the M2 with Stinger missiles. Although far less capable than the ADATS missile, the Linebacker is able to keep up with mobile heavy forces. The Linebacker has been retired from active service, while the M1097 Avenger
HMMWV-based Stinger-equipped systems have been downsized.
Most of the production M247 vehicles ended up as targets on air force bombing ranges. However, one is on display at the Sgt. Alvin C. York State Historic Park
in Pall Mall, TN where its namesake hailed from and another is located at the AAF Museum in Danville, VA.
Self-propelled anti-aircraft weapon
An anti-aircraft vehicle, also known as a self-propelled anti-aircraft weapon or self-propelled air defense system , is a mobile vehicle with a dedicated anti-aircraft capability...
(SPAAG), developed by Ford Aerospace
Ford Aerospace
Ford Aerospace & Communications Corp. was the aerospace and defense business of Ford Motor Company. It consisted of the Space Systems Division and the Western Development Labs .Partial company timeline:*1956 Aeronutronic becomes Ford Motor Company division.*1961 Ford Motor Company...
in the late 1970s. Based on the M48 Patton
M48 Patton
The M48 Patton is a medium tank that was designed in the United States. It was the third and final tank to be officially named after General George S. Patton, commander of the U.S. Third Army during World War II and one of the earliest American advocates for the use of tanks in battle It was a...
tank, it replaced the Patton's turret with a new one that featured twin radar
Radar
Radar is an object-detection system which uses radio waves to determine the range, altitude, direction, or speed of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. The radar dish or antenna transmits pulses of radio...
-directed 40 mm rapid-fire guns. The vehicle was named after Sergeant Alvin York
Alvin York
Alvin Cullum York was one of the most decorated American soldiers in World War I. He received the Medal of Honor for leading an attack on a German machine gun nest, taking 32 machine guns, killing 28 German soldiers and capturing 132 others...
, a famous World War I
World War I
World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...
hero.
The Sergeant York was intended to fight alongside the M1 Abrams
M1 Abrams
The M1 Abrams is a third-generation main battle tank produced in the United States. It is named after General Creighton Abrams, former Army Chief of Staff and Commander of US military forces in Vietnam from 1968 to 1972. The M1 is a well armed, heavily armored, and highly mobile tank designed for...
and M2 Bradley
M2 Bradley
The Bradley Fighting Vehicle is an American fighting vehicle platform manufactured by BAE Systems Land and Armaments, formerly United Defense.As with other infantry fighting vehicles, the Bradley is designed to transport infantry with armor protection while providing covering fire to suppress enemy...
fighting vehicles in the U.S. Army, in a role similar to the Soviet ZSU-23-4
ZSU-23-4
The ZSU-23-4 "Shilka" is a lightly armored, self-propelled, radar guided anti-aircraft weapon system . ZSU stands for Zenitnaya Samokhodnaya Ustanovka , meaning "anti-aircraft self-propelled mount". The "23" signifies the bore diameter in millimeters. The "4" signifies the number of gun barrels. It...
and German Gepard
Flugabwehrkanonenpanzer Gepard
The Flugabwehrkanonenpanzer Gepard is an autonomous, all-weather-capable German self-propelled anti-aircraft gun . It was developed in the 1960s and fielded in the 1970s, and has been upgraded several times with the latest electronics...
. It would replace the M163 Vulcan Air Defense System
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 MIM-72 Chaparral, ad-hoc systems of limited performance that had been introduced when the more advanced MIM-46 Mauler
MIM-46 Mauler
The General Dynamics MIM-46 Mauler was a self-propelled anti-aircraft missile system designed to a late 1950s US Army requirement for a system to combat low-flying high-performance tactical fighters and short-range ballistic missiles...
failed to mature.
Despite the use of many off the shelf
Commercial off-the-shelf
In the United States, Commercially available Off-The-Shelf is a Federal Acquisition Regulation term defining a nondevelopmental item of supply that is both commercial and sold in substantial quantities in the commercial marketplace, and that can be procured or utilized under government contract...
technologies that were intended to allow rapid and low-cost development, a series of technical problems and massive cost overruns resulted in the cancellation of the project in 1985.
Prior efforts
The first effective SPAAG in U.S. Army service was the all-manual M19 Gun Motor Carriage, based on the chassis of the M24 Chaffee. The turret of the M19 was later modified and mounted onto the M42 Duster which was based on the M41 Walker Bulldog light tank chassis. While capable for the era it was designed in, by the time it reached widespread service in the late 1950s it was clear that it was ineffective against high-speed jet-powered targets. The Duster was completely removed from service by 1963, only to be re-introduced briefly during the Vietnam WarVietnam War
The Vietnam War was a Cold War-era military conflict that occurred in Vietnam, Laos, and Cambodia from 1 November 1955 to the fall of Saigon on 30 April 1975. This war followed the First Indochina War and was fought between North Vietnam, supported by its communist allies, and the government of...
when its replacement never arrived.
The first proposed replacement for the Duster was 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 referred to the six-barreled 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...
proposed as the basis for a new SPAAG. Although the gun was extremely powerful, at some point in the late 1950s the Army decided that all gun-based systems were out of date.
The next proposed replacement for the Duster was the ambitious MIM-46 Mauler
MIM-46 Mauler
The General Dynamics MIM-46 Mauler was a self-propelled anti-aircraft missile system designed to a late 1950s US Army requirement for a system to combat low-flying high-performance tactical fighters and short-range ballistic missiles...
. Mauler mounted a nine-missile magazine on top of an adapted 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, along with detection and tracking radars. Mauler featured a completely automatic fire control system, with the operators simply selecting targets and pressing "OK". It would be able to respond to low-flying high-speed targets at any angle out to a range of about five miles. However, Mauler proved to be beyond the state-of-the-art and ran into intractable problems during development. Realizing it was not going to enter service any time soon, it was downgraded to a technology demonstration program in 1963, and eventually cancelled outright in 1965.
Still lacking an effective anti-aircraft system, the Army started development of two stop-gap systems that were meant to operate in concert. 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...
combined 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...
cannon, the M113 chassis, and an all-optical fire control system with a simple lead-computing gunsight. Suitable for "snap shots" against nearby targets, the VADS system was equipped only with a small ranging radar for the gunsight, its firing range being too small to justify a larger tracking radar. VADS was intended to operate in concert with the MIM-72 Chaparral, which combined the 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 with a more heavily modified version of the M113 chassis. The Chaparral's AIM-9D missiles were capable of tail-chase launches only, but offered ranges up to 5 miles. Also using an all-optical firing system, the Chaparral nevertheless required the operator to "settle" the missiles on the target for a period of time to allow them to lock on, limiting its ability to deal with quickly moving targets. Both vehicles were optionally supported by the 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:...
(FAAR), but this system was towed by the Gama Goat
Gama Goat
The Gama Goat was a six-wheel-drive semi-amphibious off-road vehicle originally developed for use by the US Military for the War in Vietnam. It was famous for an articulated body, which allowed it to travel over exceptionally rough terrain and for a unique four-wheel steering arrangement with the...
and could not be used near the front line
Front line
A front line is the farthest-most forward position of an armed force's personnel and equipment - generally in respect of maritime or land forces. Forward Line of Own Troops , or Forward Edge of Battle Area are technical terms used by all branches of the armed services...
s. The pair of weapons was, at best, a nuisance to the enemy and had limited performance against modern aircraft.
At one point the Army started to become concerned about developments in sensor technologies that would allow attacks by fixed-wing aircraft at night or in bad weather. They developed a requirement for a weapon system able to operate using FLIR and a laser rangefinder in order to counter these threats. However, the rest of the military establishment disapproved of the idea; even the US Air Force was able to carry out only limited operations in bad weather, and the Soviets had a considerably less capable force in this regard. The idea gained little traction and died.
Pop-up problems
During the late 1960s the combination of helicopterHelicopter
A helicopter is a type of rotorcraft in which lift and thrust are supplied by one or more engine-driven rotors. This allows the helicopter to take off and land vertically, to hover, and to fly forwards, backwards, and laterally...
anti-tank missiles improved to the point where they became a major threat to armored operations. The U.S. led the field with their TOW missile
BGM-71 TOW
The BGM-71 TOW is an anti-tank missile. "BGM" is a weapon classification that stands for "Multiple Environment , Surface-Attack , Missile ". "TOW" is an acronym that stands for "Tube-launched, Optically-tracked, Wire command data link, guided missile"...
on the Cobra gunship
AH-1 Cobra
The Bell AH-1 Cobra is a two-bladed, single engine attack helicopter manufactured by Bell Helicopter. It shares a common engine, transmission and rotor system with the older UH-1 Iroquois...
, demonstrating this powerful combination in combat in 1972's Easter Offensive. The Soviets initially lagged the U.S., but the introduction of the 9K114 Shturm missile on the Mil Mi-24
Mil Mi-24
The Mil Mi-24 is a large helicopter gunship and attack helicopter and low-capacity troop transport with room for 8 passengers. It is produced by Mil Moscow Helicopter Plant and operated since 1972 by the Soviet Air Force, its successors, and by over thirty other nations.In NATO circles the export...
in the 1970s offered the USSR a level of parity.
Unlike fixed-wing aircraft, attack helicopters had the ability to loiter near the front behind cover and pick their targets. They would then "pop up", launch a missile, and return to cover as soon as the missile hit its target. Using fast-reacting wire-guided
Wire-guided missile
A wire-guided missile is a missile that is guided by signals sent to it via thin wires connected between the missile and its guidance mechanism, which is located somewhere near the launch site. As the missile flies, the wires are reeled out behind it...
or radio-command missiles meant the total engagement time was kept to a minimum, as there was little or no "lock-on" time required; the operator simply fired and adjusted the missile's flight path onto the target while it flew. Against these targets, the Vulcan/Chaparral combination was effectively useless. The Vulcan could react quickly enough to the fleeting targets, but its 20 mm gun had an effective range of only about 1,200 meters, far shorter than the 3,000 to 5,000 meters range of the "Spiral". While the Chaparral had enough range to engage the "Hind", its lengthy lock-on period meant the Hind would have hit its target and hidden behind terrain again before the Sidewinder would reach it. Additionally, the older Sidewinder missiles used on Chaparral homed in on exhaust, and had very limited capability against helicopters faced head-on.
The limited effectiveness of the Vulcan/Chaparral was not the only problem the US Army was facing in the late 1970s. At the time they were also in the process of introducing the new M1 Abrams
M1 Abrams
The M1 Abrams is a third-generation main battle tank produced in the United States. It is named after General Creighton Abrams, former Army Chief of Staff and Commander of US military forces in Vietnam from 1968 to 1972. The M1 is a well armed, heavily armored, and highly mobile tank designed for...
and M2 Bradley
M2 Bradley
The Bradley Fighting Vehicle is an American fighting vehicle platform manufactured by BAE Systems Land and Armaments, formerly United Defense.As with other infantry fighting vehicles, the Bradley is designed to transport infantry with armor protection while providing covering fire to suppress enemy...
vehicles, which had dramatically improved cross-country performance. The M113-based Vulcan and Chaparral could not keep up with them on the advance, and would leave them open to attack in a fast moving front.
Finally, the Soviets were widely introducing the ZSU-23-4
ZSU-23-4
The ZSU-23-4 "Shilka" is a lightly armored, self-propelled, radar guided anti-aircraft weapon system . ZSU stands for Zenitnaya Samokhodnaya Ustanovka , meaning "anti-aircraft self-propelled mount". The "23" signifies the bore diameter in millimeters. The "4" signifies the number of gun barrels. It...
"Shilka", which was cause for some concern after it appeared in the Middle East. Israeli pilots attempting to avoid fire from Syrian SA-6 batteries would fly low, directly into the Shilka's envelope. Several aircraft were lost or damaged.
DIVAD
For all of these reasons, the Army developed the "Advanced Radar-directed Gun Air Defense System" (ARGADS) requirement for a new weapon system combining the reaction speed of the Vulcan with the range of the Chaparral, and placing them on a chassis that could keep up with the new tanks in combat. They also worked in the earlier FLIR/laser requirement. The system was later re-named "Division Air Defense" (DIVAD).At the time, most U.S. military policy was based on the US Air Force quickly gaining air superiority and holding it throughout a conflict. In keeping with this, the Army had previously placed relatively low priority on anti-aircraft weapons. This gave them time to mature through testing and shakedowns. In the case of DIVADs the threat was considered so serious and rapidly developing that the Army decided to skip the traditional development period and try to go straight into production by using a number of "off-the-shelf" parts. Colonel Russell Parker testified before the Senate Armed Services Committee in March 1977 that "We expect this somewhat unorthodox approach to permit a much reduced development time, thus resulting in an earliest fielding date, albeit with higher but acceptable risks... the manufacturer will be required by the fixed price warranty provisions, to correct deficiencies." It was claimed that this would cut up to five years from the development cycle, although it would require problems to be found and fixed on the operational vehicles.
Colonel Parker unveiled the DIVAD plan to 49 industry representatives on 18 May 1977. The DIVADs requirement demanded that the entrants be based on the M48 Patton
M48 Patton
The M48 Patton is a medium tank that was designed in the United States. It was the third and final tank to be officially named after General George S. Patton, commander of the U.S. Third Army during World War II and one of the earliest American advocates for the use of tanks in battle It was a...
tank chassis, provided by the Army, which were held in large quantities in surplus depots. DIVAD called for the gun to acquire a target and start firing within five seconds (later extended to eight) of it becoming visible or coming into its 3,000 m range, and had to have a 50% chance of hitting a target with a 30 round burst. In addition to all-weather capability, it also needed to have optical aiming capabilities, including a FLIR and laser rangefinder.
Entrants
Several companies responded to the DIVADs contest.Sperry Rand entered a system based on their older Vigilante gun, modified to fire the 35 mm round from the Oerlikon KDA
Oerlikon 35 mm twin cannon
The Oerlikon 35 mm twin cannon is a towed anti-aircraft gun made by Oerlikon Contraves . The system was originally designated as 2 ZLA/353 ML but this was later changed to GDF-001...
series, widely used in NATO in the anti-aircraft role. The gun could be fired at 3,000 rounds per minute for anti-aircraft use, or 180 rounds per minute for use against ground targets, fed from a 1,464 round magazine. The aluminium turret was topped by two radars and an IFF
Identification friend or foe
In telecommunications, identification, friend or foe is an identification system designed for command and control. It is a system that enables military and national interrogation systems to identify aircraft, vehicles, or forces as friendly and to determine their bearing and range from the...
system, all from Sperry.
General Electric
General Electric
General Electric Company , or GE, is an American multinational conglomerate corporation incorporated in Schenectady, New York and headquartered in Fairfield, Connecticut, United States...
entered a version with a small turret mounting their 30 mm GAU-8 Avenger
GAU-8 Avenger
The General Electric GAU-8/A Avenger is a 30 mm, hydraulically-driven seven-barrel Gatling-type rotary cannon that is mounted on the United States Air Force's Fairchild Republic A-10 Thunderbolt II. It is among the largest, heaviest and most powerful aircraft cannons in the United States military...
cannon from the A-10 Thunderbolt II
A-10 Thunderbolt II
The Fairchild Republic A-10 Thunderbolt II is an American single-seat, twin-engine, straight-wing jet aircraft developed by Fairchild-Republic in the early 1970s. The A-10 was designed for a United States Air Force requirement to provide close air support for ground forces by attacking tanks,...
. It included a single search/track radar adapted from the earlier FAAR, although they later suggested an improved system.
Raytheon
Raytheon
Raytheon Company is a major American defense contractor and industrial corporation with core manufacturing concentrations in weapons and military and commercial electronics. It was previously involved in corporate and special-mission aircraft until early 2007...
proposed using the turret from the Dutch version of the German Gepard flakpanzer
Flugabwehrkanonenpanzer Gepard
The Flugabwehrkanonenpanzer Gepard is an autonomous, all-weather-capable German self-propelled anti-aircraft gun . It was developed in the 1960s and fielded in the 1970s, and has been upgraded several times with the latest electronics...
. Most of the turret remained the same as the original Gepard, including the twin 35 mm Oerlikon KDA cannons, but used Hollandse Signaalapparaten
Thales Nederland
Thales Nederland B.V. is a subsidiary of Thales Group involved primarily in naval defence systems...
radars and an 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...
fire-control computer. Raytheon demonstrated that the turret, although designed for the Leopard 1, could be mounted on the M48 with some adaptation.
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...
' entry also mounted twin Oerlikon KDA cannons, but mounted them side-by-side in a new aluminum turret, as opposed to either side of the turret as in the Gepard. They could be fired in either the automatic or semiautomatic mode, and their combined rate of fire was 1,100 rounds per minute from a 600 round magazine. The radar and fire control systems were derived from their Phalanx CIWS
Phalanx CIWS
The Phalanx CIWS is an anti-ship missile defense system. It is a close-in weapon system and was designed and manufactured by the General Dynamics Corporation, Pomona Division...
system, with the tracking radar mounted on the front of the turret, beside the guns, and the search radar on top. The turret also included independently stabilized optical sights and a laser range finder for manual engagements.
Ford Aerospace
Ford Aerospace
Ford Aerospace & Communications Corp. was the aerospace and defense business of Ford Motor Company. It consisted of the Space Systems Division and the Western Development Labs .Partial company timeline:*1956 Aeronutronic becomes Ford Motor Company division.*1961 Ford Motor Company...
's entry was based around the Bofors 40 mm L/70 cannons, twin-mounted in the center of the turret in a fashion similar to the General Dynamics entry. The relatively large and boxy turret also mounted separate long-range search and short-range tracking radars on top. The radars were mounted on booms to give them a clear view of the sky, and both had the ability to be folded down to reduce the vehicle's height during travel. The tracking radar was a modified version of the Westinghouse AN/APG-66 from the F-16 Fighting Falcon
F-16 Fighting Falcon
The General Dynamics F-16 Fighting Falcon is a multirole jet fighter aircraft originally developed by General Dynamics for the United States Air Force . Designed as an air superiority day fighter, it evolved into a successful all-weather multirole aircraft. Over 4,400 aircraft have been built since...
. Like the GD entry, it also mounted a complete optical sighting and ranging system.
Some critics claim that Ford's use of the 40 mm Bofors appears to have been a business decision, not a technical one. While the 35 mm round was already a widely accepted NATO standard and was technically well respected, Ford had a marketing agreement with Bofors
Bofors
The name Bofors has been associated with the iron industry for more than 350 years.Located in Karlskoga, Sweden, the company originates from the hammer mill "Boofors" founded 1646. The modern corporate structure was created in 1873 with the foundation of Aktiebolaget Bofors-Gullspång...
. As Gregg Easterbrook
Gregg Easterbrook
Gregg Edmund Easterbrook is an American writer, lecturer, and a senior editor of The New Republic. His articles have appeared in Slate, The Atlantic Monthly, The New York Times, The Washington Post, The Los Angeles Times, Reuters, Wired, and Beliefnet. In addition, he was a fellow at the...
later reported:
- Immediately the lobbying began. Ford had a marketing agreement with the Swedish firm Bofors, a maker of 40-mm but not 35-mm cannons; while Ford could have switched to a 35-mm weapon for DIVAD, the potential profits from a 40-mm weapon were higher. Department of Defense lawyers, the Army pleading to Congress, had advised that specifying the caliber DIVAD's gun would be 'anti-competitive' and could lead to lawsuits-'the most ludicrous excuse I've ever heard' a high-ranking Pentagon official had told me. When the final DIVAD requirements were issued they called for a gun 'in the 30-mm to 40-mm range'.
However, the Bofors 40 mm cannon also had worldwide popularity. In addition, FACC had developed a proximity-sensing round for the 40 mm, which increased probability of a kill, and the shell carried either a greater explosive charge or higher deadweight mass than the smaller anti-aircraft platforms. These factors would be important in the primary scenario for which the DIVAD was to be deployed, that being the large-theater land operations vs the Warsaw Pact
Warsaw Pact
The Warsaw Treaty Organization of Friendship, Cooperation, and Mutual Assistance , or more commonly referred to as the Warsaw Pact, was a mutual defense treaty subscribed to by eight communist states in Eastern Europe...
.
Development
On 13 January 1978, General Dynamics and Ford were given development contracts for one prototype each, the XM246 and XM247 respectively, to be delivered to Fort BlissFort Bliss
Fort Bliss is a United States Army post in the U.S. states of New Mexico and Texas. With an area of about , it is the Army's second-largest installation behind the adjacent White Sands Missile Range. It is FORSCOM's largest installation, and has the Army's largest Maneuver Area behind the...
in June 1980. On schedule, both companies delivered their prototypes to the North McGregor Test Facility and head-to-head testing began. The shoot-off was delayed for two months "because the prototypes which arrived at Fort Bliss test range were too technically immature." In the DT/OT II test series they shot down two F-86 Sabre
F-86 Sabre
The North American F-86 Sabre was a transonic jet fighter aircraft. Produced by North American Aviation, the Sabre is best known as America's first swept wing fighter which could counter the similarly-winged Soviet MiG-15 in high speed dogfights over the skies of the Korean War...
fighters, five UH-1 Huey helicopters and twenty-one smaller drones.
After the 29-month Phase One trial, Ford's entry was selected as the winner of the DIVADs contest on 7 May 1981, and given a fixed-price $6.97 billion development and initial production contract for deliveries at various rates. The system was officially named M247 Sergeant York when the contract was awarded. The decision was controversial, as the GD entry had "outscored" the Ford design consistently in testing, nineteen "kills" to nine by most accounts.
Ford's prototype vehicle started demonstrating problems almost immediately. The main concerns had to do with the tracking radar, which demonstrated considerable problems with ground clutter. In testing, it was unable to distinguish between helicopters and trees. When the guns were pointed upward to fire on high-angle targets, the barrels projected into the radar's line of sight and further confused the system. Additionally, the reaction time was far too slow; against hovering helicopters it was 10 to 11 seconds, but against high-speed targets it was from 11 to 19, far too long to take a shot.
The RAM-D (reliability, availability, maintainability and durability) tests ran from November 1981 to February 1982, demonstrating a wide range of operation concerns. The turret proved to have too slow a traverse to track fast moving targets, and had serious problems operating in cold weather, including numerous hydraulic leaks. The simple electronic counter-countermeasures
Electronic counter-countermeasures
Electronic counter-countermeasures is a part of electronic warfare which includes a variety of practices which attempt to reduce or eliminate the effect of electronic countermeasures on electronic sensors aboard vehicles, ships and aircraft and weapons such as missiles. ECCM is also known as...
(ECCM) suite could be defeated by only minor jamming. The used guns taken from U.S. Army stock were in twisted condition due to careless warehousing. Perhaps the most surprising problem was that the 30-year-old M48 chassis with the new 20-ton turret meant the vehicle had trouble keeping pace with the newer M1 and M2, the vehicles it was meant to protect.
In February 1982 the prototype was demonstrated for a group of US and British officers at Fort Bliss, along with members of Congress and other VIPs. When the computer was activated, it immediately started aiming the guns at the review stands, causing several minor injuries as members of the group jumped for cover. Technicians worked on the problem, and the system was restarted. This time it started shooting towards the target, but fired into the ground 300 m in front of the tank. In spite of several attempts to get it working properly, the vehicle never successfully engaged the sample targets. A Ford manager claimed that the problems were due to the vehicle being washed for the demonstration and fouling the electronics. In a report on the test, Easterbrook jokingly wondered if it ever rained in central Europe.
As early production examples started rolling off the production line, the problems proved to be just as serious. One of the early models is reported to have locked onto a latrine fan, mistaking its return for a moving target of low-priority. Reporting on the incident in another article on the vehicle's woes, Easterbrook reported that "During a test one DIVAD locked on to a latrine fan. Michael Duffy, a reporter for the industry publication Defense Week, who broke this aspect of the story, received a conference call in which Ford officials asked him to describe the target as a 'building fan' or 'exhaust fan' instead."
Nevertheless, the program's manager within the Army was cautiously positive. Major General Maloney said, "The DIVAD battery-eight systems plus one spare-activated 1 November 1984, at Fort Bliss to prepare for tests, has been demonstrating 90% reliability for full systems capability. The systems have been able to operate in a degraded manner a further 2% of the time and have had an 8% inoperable rate." He later stated that the “gun still had problems with software and electronic countermeasures, but my sensing was that it was certainly no worse than many weapon systems at this period in their gestation.”
Cancellation
In spite of the bad press and development problems, the Army continued to press for the system's deployment as they had no other system in the pipeline to replace it. To add to the problems, another generation of Soviet helicopter and missile designs was pushing their envelope out to 6,000 m, rendering DIVADs ineffective at long range. In response, the Army announced it would consider adding the Stinger missileFIM-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...
to the DIVAD system, leading to even more cries about its ineffectiveness.
As Washington became increasingly fed up with the DIVAD's problems, Secretary of Defense Caspar Weinberger
Caspar Weinberger
Caspar Willard "Cap" Weinberger , was an American politician, vice president and general counsel of Bechtel Corporation, and Secretary of Defense under President Ronald Reagan from January 21, 1981, until November 23, 1987, making him the third longest-serving defense secretary to date, after...
ordered a $54 million series of battlefield-condition tests. Congress authorized production money to keep the program alive through a test-fix-test cycle but with a caveat; the funds would be released only if Weinberger certified that the gun "meets or exceeds the performance specifications of its contract." The tests were monitored by the Pentagon's new Operational Test and Evaluation Office (OT&E), mandated by Congress in 1983 to serve as an independent watchdog. The tests were carried out late in 1984.
The results were abysmal. Unable to hit drones moving even in a straight line, the tests were later relaxed to hovering ones. The radar proved unable to lock even to this target, as the return was too small. The testers then started adding radar reflectors to the drone to address this "problem", eventually having to add four. Easterbrook, still covering the ongoing debacle, described this as being similar to demonstrating the abilities of a bloodhound
Bloodhound
The Bloodhound is a large breed of dog which, while originally bred to hunt deer and wild boar, was later bred specifically to track human beings. It is a scenthound, tracking by smell, as opposed to a sighthound, which tracks using vision. It is famed for its ability to discern human odors even...
by having it find a man standing alone in the middle of an empty parking lot, covered with steaks. The system now tracked the drone, and after firing a lengthy burst of shells the drone was knocked off target. As it flew out of control, the range safety officer had it destroyed by remote control. This was interpreted by the press as an attempt to "fake" the results, describing it as "sophomoric deceits". From that point on, every test success was written off as faked.
The OT&E concluded that the gun could perform the mission as originally specified, but the tests also showed that the system had considerable reliability problems, many as the result of trying to adapt a radar system developed for aircraft to the ground role. Initial production tests run from December 1984 to May 1985 turned up a continued variety of problems, failing 22 of 163 contract requirements, and 22 serious failures in operational readiness. Contrary to the Army's earlier reports, OT&E Director Jack Krings said the tests showed, "the SGT YORK was not operationally effective in adequately protecting friendly forces during simulated combat, even though its inherent capabilities provided improvement over the current [General Electric] Vulcan gun system. The SGT YORK was not operationally suitable because of its low availability during the tests." They measured the availability of the system at 33%, as opposed to the required 90%.
On 27 August 1985, Secretary of Defense Caspar Weinberger
Caspar Weinberger
Caspar Willard "Cap" Weinberger , was an American politician, vice president and general counsel of Bechtel Corporation, and Secretary of Defense under President Ronald Reagan from January 21, 1981, until November 23, 1987, making him the third longest-serving defense secretary to date, after...
killed the project after about 50 vehicles had been produced. He said, "the tests demonstrated that while there are marginal improvements that can be made in the York gun, they are not worth the additional cost-so we will not invest any more funds in the system." Noting that cancelling the project did not imply a lack of need, he started the process of studying a missile-based system to fill the same niche. This led to the Oerlikon 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....
system, which suffered problems of its own and entered service only in the Canadian Army
Canadian Forces Land Force Command
The Canadian Army , previously called Land Force Command, is responsible for army operations within the Canadian Forces. The current size of the Army is 19,500 regular soldiers and 16,000 reserve soldiers, for a total of around 35,500 soldiers...
. The niche was eventually filled by the M6 Linebacker, an adaptation of the M2 with Stinger missiles. Although far less capable than the ADATS missile, the Linebacker is able to keep up with mobile heavy forces. The Linebacker has been retired from active service, while the M1097 Avenger
M1097 Avenger
The Avenger Air Defense System, designated AN/TWQ-1 under the Joint Electronics Type Designation System, is a missile system which provides mobile, short-range air defense protection for ground units against cruise missiles, unmanned aerial vehicles, low-flying fixed-wing aircraft, and helicopters...
HMMWV-based Stinger-equipped systems have been downsized.
Most of the production M247 vehicles ended up as targets on air force bombing ranges. However, one is on display at the Sgt. Alvin C. York State Historic Park
Sgt. Alvin C. York State Historic Park
Sgt. Alvin C. York State Historic Park is a state park in Pall Mall, in the U.S. state of Tennessee. Situated along the Wolf River, the park contains the farm and gristmill once owned by decorated World War I soldier Alvin C. York , who lived in the Pall Mall area for most of his life...
in Pall Mall, TN where its namesake hailed from and another is located at the AAF Museum in Danville, VA.