M247 Sargeant York
The M247 Sergeant York DIVAD (Division Air Defense) was a self-propelled anti-aircraft gun (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 Bofors 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 in the U.S. Army, in a role similar to the Soviet ZSU-23-4 and German Flakpanzer Gepard. It would replace the M163 Vulcan Air Defense System SPAAG and MIM-72 Chaparral missile, ad hoc systems of limited performance that had been introduced when the more advanced MIM-46 Mauler missile failed to mature.
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 in service and fixed on the operational vehicles.
Colonel Parker unveiled the DIVAD plan to 49 industry representatives on 18 May 1977. The DIVAD's 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.
Several companies responded to the DIVADs contest: Sperry Rand, General Electric, Raytheon, General Dynamic, and Ford Aerospace. 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 Bliss in June 1980. On schedule, both companies delivered their prototypes to the North McGregor Test Facility and head-to-head testing began. 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 General Dynamics 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.[16] 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 toward the target, but fired into the ground 300 metres (980 ft) 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, a reporter jokingly wondered if it ever rained in central Europe.
In February 1984 the Defense Department sent a "cure-notice" censuring Ford Aerospace for numerous "totally unacceptable" delays in the program. In March 1984 the Army took delivery, six months late, of the first production model for testing.
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 metres (6,600 yd), rendering DIVADs ineffective at long range. In response, the Army announced it would consider adding the Stinger missile 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 Director, Operational Test and Evaluation Office (DOT&E), mandated by Congress in 1983 to serve as an independent watchdog. The tests were carried out late in 1984.
The results were abysmal. When the gun proved unable to hit drones moving even in a straight line, the tests were relaxed to hovering targets. 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. 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.
On 27 August 1985, 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."
Most of the production Sergeants York 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, one is in the Wahner E. Brooks Historical Exhibit at the U.S. Army Yuma Proving Grounds, AZ, another is located at the AAF Museum in Danville, VA, one at the Fort Snelling Military Museum in Minneapolis, MN (now closed), and one located at the Arkansas National Guard Museum at Camp Robinson, North Little Rock, Arkansas.