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97-512: T43 may refer to: Vehicles [ edit ] T-43 medium tank , a World War II Soviet medium tank T43 heavy tank , a pre-production model of the American M103 Heavy Tank T43-class minesweeper , a Soviet-designed minesweeper Boeing T-43 , a 1973 United States Air Force military training and transport aircraft Cooper T43 , a 1958 racing car SJ T43 ,

194-667: A fire control system (FCS) in the M48. The fire control system included a rangefinder, mechanical ballistic computer, ballistic drive, and gunner's sight. Collectively, these mechanical devices resembled in miniature the fire control systems used in naval gunnery . Only after the Second World War did such systems become small enough for use in combat vehicles. These mechanical fire control systems permitted tanks to engage effectively at much longer ranges than in World War II ,

291-405: A stereoscopic model range determination occurred by measuring the distance from the observer to a target using the observer's capability of binocular vision . The coincidence rangefinder uses a single eyepiece. Light from the target enters the rangefinder through two windows located at either end of the instrument. The ARCOVE emphasis upon increased long range accuracy led to the incorporation of

388-751: A $ 200 million contract to become the sole producer of the M48A2 and started production at its Grand Blanc Tank Plant in Michigan in April 1953. The decision raised skepticism among lawmakers. Senator Estes Kefauver noted the move would effectively leave GM as the only producer of light (the M41 Walker Bulldog ) and medium tanks when the Chrysler production contract for M48A1 production was set to expire in April 1956. Months later Chrysler underbid GM in

485-610: A $ 200 million contract to start producing the tank in 1953 at the Schenectady Tank Plant in New York. All four companies were given initial production contracts in that same year for around 400 tanks each. The first Chrysler production tank was unveiled on 1 July 1952 as the 90mm Gun Tank M48 and christened the M48 Patton by Mrs. Beatrice Ayer Patton, widow of the late General George S Patton . The M48 featured

582-467: A 1963 Swedish diesel-electric locomotive Slingsby T.43 Skylark 3 , a British glider Other uses [ edit ] T43 (classification) , a disabled sports handicap class for leg amputees IBM ThinkPad T43 , a laptop model [REDACTED] Topics referred to by the same term This disambiguation page lists articles associated with the same title formed as a letter–number combination. If an internal link led you here, you may wish to change

679-456: A G305 cupola riser with 9 non-removable vision blocks installed (some versions had 7 with the 2 rear blocks deleted) between the turret roof and the cupola. It also came with a new bulged hatch cover to provide the tank commander with more headroom and allowed him to reload the weapon while remaining under armor protection. A major drawback of both these cupolas was their inability to mount either daylight or infrared vision devices. The receiver of

776-620: A broad production base in favor of Wilson's "single, efficient producer" concept. In September Wilson chose General Motors over Chrysler to take over production of the M48 Patton . General Motors would also become heir to any additional T43 orders after Chrysler tank production wrapped up in June 1954. Testing was unsatisfactory, with the tanks failing to meet Continental Army Command's standards and being put into storage in August 1955. Following

873-650: A critical consideration for the Army, expecting to enter the European battlefield outnumbered. Instead of a gunner's sight being slaved to the gun tube, the ballistic computer and drive computed the range and elevated the gun. The gunner's primary responsibility lay in keeping the sight on the target. The mechanical ballistic computer made a more accurate computation of range possible by mathematically accounting for such factors as vehicle cant and ammunition type. Many developmental range finders based on pulses of IR light, such as

970-533: A distance of 1,000 yd (910 m), but was not accepted for service. Instead it was decided to use an improved version of the 90 mm gun, the T139 for the M48 production tanks. It allowed for easier barrel changing and weighed less than the preceding M36/T119 gun. It was later standardized as the 90mm Gun M41 in February 1951. The T48 and M48(Mod A) tanks featured a remote controllable machine gun mount as

1067-497: A fast, highly mobile, fully armored, lightweight vehicle. It must be able to swim, cross any terrain, and climb 30 degree hills. It must be air-transportable. It must have a simple but powerful engine, requiring little or no maintenance. The operating range should be several hundred miles. We would also like it to be invisible". The T48 project was to focus on improving the turret of the M47 Patton and upgrading performance with

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1164-731: A gasoline-powered engine, different models were used depending on availability and manufacturer. Originally the M48(Mod A) that was built by Chrysler Defense at the OTAC Test Center (T48 Pilot #1) in 1951 used the Continental AV-1790-5B coupled to a General Motors CD-850-4A cross-drive transmission as used for the M47. The M48s built by American Locomotive used a Continental AV-1790-5C gasoline engine and either an Allison CD-850-4A or 4B cross-drive transmission. Additionally

1261-451: A maximum output of 810 horsepower (600 kW) and 1,600 pound-feet (2,200 N⋅m) of torque, fed through a General Motors CD-850-4 two-speed transmission. This allowed the 60-short-ton (54 t; 54-long-ton) heavy tank to achieve a maximum road speed of 21 miles per hour (34 km/h) and a maximum climbing gradient of 60%. Initial production versions suffered a host of drivetrain mechanical problems. The Continental powerpack, shared by

1358-573: A more powerful yet more efficient gasoline engine. 1/4 and 1/8 scale design mockups of the turret were constructed during May 1950 using the T119 90mm main gun of the M47 Patton . The design study was accepted by the Army in December and a contract for the advanced production design and engineering (APE) of a 90mm armed tank was awarded to the Chrysler Defense. Hull redesign included moving

1455-533: A simple but powerful engine, requiring little or no maintenance. The operating range should be several hundred miles. We would also like it to be invisible". Some ideas proposed were to utilize a nuclear fission power plant in the R-32 or a vapor-cycled power plant fueled by hydrocarbons in the Chrysler TV-8 tank. In response to these findings an eventual replacement for the M48A2 was recommended. ARCOVE and

1552-534: A total of 18 tanks per company. Standard US Army armor battalions at the time had three companies per battalion, each with three five-tank platoons, with 17 tanks per company (two tanks were in headquarters platoon). One of the flaws of M103 vehicle was it did not have adequate reliability in retreat operations. US Army was aware that more Tiger tanks had been lost during retreat operations than during actual combat, and US Army in Europe could not afford that. In Europe it

1649-425: A two-cylinder, gasoline, air-cooled engine (sometimes referred to as the "Little Joe" by tank crews) was provided to power a 28 volt, 300 ampere generator when the main engine was not needed. Fuel capacity was 200 US gal (760 L) providing a cruising range of about 70 mi (110 km). The suspension consisted of six roadwheel pairs with a torsion bar suspension system and five return rollers. There

1746-887: The Korean War . This forced the US to field older tank models, such as the M26 Pershing and M46 Patton . In response, the Army launched several design projects for a replacement of the M46 and M26. The United States entered a period of frenzied activity during the crisis atmosphere of the Korean War, when America seemed to lag behind the Soviet Union in terms of tank quality and quantity. Testing and development cycles occurred simultaneously with production to ensure speedy delivery of new tanks. Such rapid production caused problems but

1843-752: The Newark Tank Plant in Newark, Delaware, in March 1951 to produce the M48 while Chrysler Defense Engineering and ARCOVE continued advanced production engineering (APE) to evolve the design using the T48 prototypes at the OTAC Detroit Arsenal. In May 1952 Chrysler agreed to take control of a Government-Owned and Contractor Operated (GOCO) basis of the Newark Tank plant production facility with

1940-688: The Armor School at Fort Knox to train crewmembers and maintenance personnel. The Army concluded in January 1952 that the T42 had failed as a tank capable of combat in Europe against Soviet tanks and reached the same conclusion in November 1953 for the M48 Mod A versions. The M48A1 focused on improving the engine and the vehicle's operational range and fixing numerous mechanical problems. To cope with

2037-531: The Cold War M48 Patton 177.8 km (110.5 mi) The M48 Patton is an American first-generation main battle tank (MBT) introduced in February 1952, being designated as the 90mm Gun Tank: M48 . It was designed as a replacement for the M26 Pershing , M4 Sherman , M46 and M47 Patton tanks, and was the main battle tank of the U.S. Army and U.S. Marine Corps in

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2134-612: The Congress would not approve the procurement of the M48A2 after the fiscal year 1959. However, the ongoing T95 Tank Program was progressing slowly as its new technologies were being developed. Several ideas were proposed to replace the M48A2. General Bruce C. Clarke wrapped competing and even conflicting desires in irony, observing that "We know exactly what we want. We want a fast, highly mobile, fully armored, lightweight vehicle. It must be able to swim, cross any terrain, and climb 30-degree hills. It must be air-transportable. It must have

2231-437: The Continental AV-1790-5B gasoline engine producing 704 brake horsepower coupled to an Allison CD-850-4A cross-drive transmission with 2 forward and 1 reverse ranges. The hull armor was increased to 4 in (100 mm) on the front glacis of rolled homogeneous steel. It had six roadwheel pairs per side and five return rollers, a torsion bar suspension system, and used T97E2 steel tracks. A new hemisphere-shaped turret eliminated

2328-647: The Deputy Chief of Staff, Logistics (DCSLOG) submitted a proposal for a tank based on the M48A2 featuring improved firepower and a compression ignition engine and started the design development of the XM60 in September 1957. The engine deck was redesigned with two large louvered doors that replaced the complicated grill work of the rear engine decks of the M48/M48A1 hull designs. This new rear hull arrangement on

2425-507: The M103 was built with a two-piece, cast elliptic armor scheme, similar to the M48's design. It featured seven road wheels per side, mounted with long-arm independent torsion bars. The 28-inch (71 cm) track was shoed in steel backed rubber chevron tracks, allowing for a ground pressure of 12.9 psi (89 kPa). The Continental AV-1790 engine was placed at the rear of the tank, and produced

2522-506: The M103s were rather overkill and expensive to deal with T-54 and T-55 tanks. The US Marine Corps assigned one M103 company to each of its three Marine tank battalions, including its Marine reserve units. The M103 was never used in combat. While the US Army deactivated its heavy armor units with the reception of the new M60 series main battle tanks in 1963, the remaining M103s stayed within

2619-513: The M2HB took up a great deal of space in the already cramped cupola's interior. Also due to restraints in the cupola, smaller 50 round ammunition boxes were used. Development of its eventual replacement, the T9/M19 cupola of the XM60 tank was continued into 1958 and some M19 cupolas were retro-fitted to M48A5s to allow for the use of IR and daylight periscopes by the commander. Chrysler began building

2716-588: The M47's M36/T119 90 mm rifled main gun could not consistently penetrate its frontal armor, even with special armor-piercing capped (APC) or HEAT ammunition. Work was performed to address this by developing the improved T300E53 HEAT ammunition and the T137 series of hypervelocity armor-piercing discarding-sabot (HVAP-DS or simply APDS) ammunition for the M36 gun. The new APDS round could penetrate 11.1 in (280 mm) of homogeneous steel armor, angled at 30 degrees, at

2813-648: The M47s noted shot traps and lowered the vehicle's height. T48 pilot #1 was constructed by Chrysler Engineering to begin testing at the OTAC Detroit Arsenal Test Center in December 1951. Six prototypes were built in all. On 27 February 1951, shortly after the outbreak of the Korean War , the Ordnance Technical Committee Minutes (OTCM) #33791 initiated the simultaneous production and design refinement of

2910-519: The M48 by 1953, however its development was continued with the T95 Medium Tank until 1958. There were two different hulls used for the M48 series. The M48 hull had a wedge-shaped front glacis compared to the M46's rather flat design. Early Mod A hulls had smaller diameter driver's hatches. The suspension consisted of six roadwheel pairs per side with a torsion bar suspension system and five return rollers. The engine exhaust vents were located on

3007-504: The M48A1 (T48 Pilot #3) were further upgraded to the A2 hull design standard but retained their original 5 return roller configuration. The M48A2 hull design saw several modifications including a reduction from five to three return rollers per side. The suspension system was simplified, a more compact powerpack compartment and additional fuel cells, with large louvered grill access doors replaced

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3104-548: The M48A1 was considered an even match for its Soviet counterpart, the T-54 and fielded to combat units in Europe. On 25 October 1954, the Army decided to amend its designation of the M48 tank. Thereafter, the tanks with the original Mod A hull design and the Chrysler-designed M1 remote-control machine gun mount attached to the tank commander's pop-up hatch would remain the 90mm gun tank M48. However, all those tanks with

3201-453: The M48A2 tank helped in cooling the engine and minimizing the infrared (heat) signature of the vehicle. The suspension system was simplified. The track tensioner arm was eliminated, modifications to the idler arm, the addition of bumper springs and friction snubbers, and a relocation of the air cleaner assembly. The number of return rollers was reduced to 3 per side. With the more compact AVI-1790-8 engine, additional fuel tanks were installed in

3298-596: The M48A2C, were powered by a gasoline engine. The M48A3 and A5 versions used a diesel engine, however, gasoline engine versions were still in use in the US Army National Guard through 1968 and by many West German Army units through 1975. Numerous examples of the M48 saw combat use in various Arab–Israeli conflicts and the Vietnam War . Beginning in 1959, most American M48A1s and M48A2s were upgraded to

3395-629: The M48A3 model. The M48 Patton-series saw widespread service with the United States and NATO until it was superseded by the M60 tank . It was widely exported. The tank's hull also became the basis for a wide variety of experimental, utility and support vehicles such as armored recovery vehicles and bridge layers. Some M48A5 models served into the mid-1980s with US Army National Guard units, and M48A3s were used as targets for weapons and radar testing into

3492-467: The M5A2 ballistic drive and mechanical M13A3 gun data computer which integrated barrel temperature data with an M17 coincidence range finder. The rangefinder is a double image coincidence image instrument used as the ranging device of the gunner's primary direct sighting and fire control system. The gunner is provided with an M20 day periscope with a magnification of x8 and an M105D day telescopic sight with

3589-537: The Mod B hull (some production M48A1 tanks had the Mod B turret) and fitted with the new small turreted M1 cupola armed with a .50 caliber M2HB machine gun would be designated as the 90mm gun tank M48A1. M48A1 tanks with 5 return rollers and the ModB driver's hatch were modified to the M48A2 hull configuration. The hull's armor framing for the engine compartment was modified. In addition detachable headlights, armored boxes around

3686-536: The Optical Tracking, Acquisition and Ranging (OPTAR) rangefinder of the T95 continued into 1957. Another requirement of the T48 project was to explore the use of autoloaders for the main gun as they became available. Preliminary experiments with a loading system using the T48 turret were unsuccessful due to the limited space and the need to line up the breech with the loading system after each firing. It also

3783-569: The Soviet T-10/IS-8 tank. The frontal hull glacis was a compound pike, welded at the center seam, with up to 10-inch (250 mm) thick armor at the front. The turret was a massive single-piece cast design, fitted with heavily sloped 10-inch (250 mm) rolled-homogeneous armor. The M103 was designed to mount the 4.7 in (120 mm) M58 gun , fitted in the M89 turret mount. Using standard Armor-Piercing Ballistic Cap Tracer Rounds, it

3880-521: The T48 tanks at the OTAC Detroit Arsenal Test Center would be incorporated into the M48 series production vehicles as quickly as possible. T48 pilot #1 was designed and constructed by Chrysler Engineering to begin the APE design development at the OTAC Detroit Arsenal Test Center in December 1951. This tank was provisionally armed with the M36/T119 gun using a Y-shaped deflector and a muzzle brake. This gun

3977-498: The T48 tanks began in February 1952 and continued until the end of 1955. However, the perceived immediate threat of Soviet aggression in Western Europe and the ongoing Korean War impelled Army senior leadership to rush the T48 tank into series production before the inevitable bugs could be worked out of the new tank design. Instead, it was decided that any needed design changes uncovered by the continued testing and evaluation of

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4074-409: The U.S. Army made blueprints for a heavy tank reference design. In January 1951, it awarded Chrysler a $ 99 million contract to produce the tank. Chrysler tasked Robert T. Keller, the son of Chrysler Board Chairman K.T. Keller , with overseeing its design, and construction at the company's new Newark, Delaware , tank plant . The first T43 pilot model was completed in November 1951. Officials said

4171-631: The US Army Field Forces (AFF) declared the T42 medium tank unfit for production in November 1952, mainly due to serious shortcomings of its hull design. Ford's production of the M48 ended in August 1953 after a fire destroyed most of the Livonia Tank Plant. Testing and feedback from ARCOVE had uncovered the fact that the original driver's hatch design of the M48 Mod A hull's design (T48 pilots #1 and 2) tanks proved to be too small and made for an uncomfortable seating position for

4268-521: The US Government and continue production design refinement of the T48 at the OTAC Detroit Arsenal. To meet the urgent need for tanks, production contracts were also awarded to General Motors Fisher Body Division (Grand Blanc Tank Plant) and Ford Motor Company (Livonia Tank Plant) to produce the tank in Michigan starting in April 1952. Also in July 1952 the Army awarded American Locomotive Company

4365-571: The US Marine Corps inventory until they began receiving the M60 series main battle tank. With the disappearance of the heavy tank from US forces came the full acceptance of the main battle tank in 1960 for the US Army, and 1973 for the US Marine Corps. Although the later variants of the M1 Abrams main battle tank utilize the same caliber of main gun, 4.7 in (120 mm), the M103's cannon

4462-522: The Vietnam War. Nearly 12,000 M48s were built, mainly by Chrysler and American Locomotive Company , from 1952 to 1961. The M48 Patton was the first U.S. medium gun tank with a four-man crew, featuring a centerline driver's compartment and no bow machine gunner. As with nearly all new armored vehicles it had a wide variety of suspension systems, cupola styles , power packs, fenders and other details among individual tanks. The early designs, up to

4559-480: The approval of 98 improvements the tank was redesignated the M103 Heavy Tank in April 1956. Of the 300 T43E1s built, 80 went to the US Army (74 of which were rebuilt to M103 standard), and 220 were accepted by the US Marine Corps, to be used as infantry support, rebuilt successively to improved M103A1 and then later M103A2 standards. A House Government Operations subcommittee report in July 1957 called for

4656-629: The battlefield, and the varying calibers of main guns now available. Thus the caliber of the gun replaced its weight designation. For example, the M103 Heavy Tank was redesignated as the 120 mm Gun Tank M103 and the Light Tank M41 Walker Bulldog as the 76 mm Gun Tank M41 Walker Bulldog . The M47 Patton entered production in 1951 and was used by the United States Army and Marine Corps but ongoing technical and production problems kept it from serving in

4753-403: The commander, gunner and loader were positioned in the turret and the driver stationed in the front center of the hull. The M48's turret consisted of a redesigned flat gun shield and standard pop-up hatch for the commander's station. The M48 Mod A turret design had smaller roof hatches for both the commander and loader. A .50 cal M2HB using a M1 remote control mount on a pedestal was available for

4850-417: The commander. When not in use, the machine gun mount could be stowed on a bracket welded to the turret roof in front of the loader. The M48's direct fire control system consisted of an M12/T41 stereoscopic rangefinder with a field of view of 5 degrees and magnification of x7.5, an azimuth indicator, an M20 gunner's periscope and a T13 super elevation actuator. Two main bearings are bolted to the mounting plate on

4947-431: The complicated grill work of the rear engine decks of the M48/M48A1 hull designs. This hull was used on newly constructed M48A2 and M48A3 tanks of the M48 series. The turret used for the M48 series was hemispherical in shape and was made from cast homogeneous steel. It had a flat gun shield and a standard pop-up styled hatch for the commander and an additional hatch for the loader's station. Early production Mod A models of

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5044-632: The conclusion of World War II , the United States Ordnance Tank-Automotive Command (OTAC) drastically slowed or canceled many tank development and design programs. On 7 November 1950, the Ordnance Technical Committee mandated a change in the nomenclature for tanks in the US military. It was decided that weight designations (Light, Medium, Heavy) were no longer applicable due to changes in the way tanks were developed and employed on

5141-464: The drive sprocket at the rear and a torsion bar suspension system. Pilot #2 was built in February 1952 and also used the early Mod A design with small hatches. It was fitted with the T139/M41 90mm gun replacing the muzzle brake with a cylindrical blast deflector. A T-shaped deflector was used for production M48 tanks. This vehicle had two machine guns installed, a .30cal M1919E4 mounted coaxially to

5238-418: The driver when operating the tank with his hatch in the open position. To rectify this problem a new larger driver hatch was devised that was introduced into series production vehicles as early as possible. Also the driver's front vision block was removable and could be replaced with an infrared IR vision block. A redesigned power pack featured an AV-1790-7B gasoline engine and CD-850-4B transmission. The turret

5335-411: The driver's station to the front center and removal of the bow-mounted machine gun and its associated crew station, which was converted to safe container storage for additional main gun ammunition. The front glacis was sloped to offer much better ballistic protection than former welded and rather flat designs. An aircraft style steering wheel (a yoke ) replaced lever steering. The power pack consisted of

5432-405: The driver. T48 Pilots #1 & 2 incorporated a mechanism that dropped the three periscope heads to provide clearance for the hatch door as it swung to the right, and the driver then had to reposition the periscopes by hand once the hatch was closed again. The vehicle did not have an NBC protection system for the crew and a fording depth of approximately 1.2 m (3.9 ft). It had a crew of 4;

5529-486: The engine compartment, increasing fuel capacity to 335 gallons. Many older model M48A1s were rebuilt to this production configuration but retained their original 5 return rollers per side. The M48A2C saw improvements for the turret implementing the Mod B turret design with larger hatches for the commander and loader. The M12 rangefinder was replaced with a full-field coincidence model along with an improved turret control system. The M13 Fire Control System (FCS) consists of

5626-424: The fielding of the remaining tanks. The Marines Corps however continued to use the M47 Patton . The M48A1's width proved too wide for many European tunnels, complicating rail transport. Operational readiness rates of M48-equipped units tended to be low. The tanks continued experiencing engine, transmission, track, and suspension problems, and the M12 stereoscopic rangefinder was uncomfortable to operate. However,

5723-540: The future use of IR vision blocks by the driver. It also had 5 return rollers, 6 roadwheel pairs per side with the drive sprocket at the rear and a torsion bar suspension system. The Mod B turret also had larger hatches for the commander and loader. An additional three hulls were constructed (T48 pilots 4 through 6) in 1953. These tanks were used into 1955 for the component development of the M48A2 production tanks including fire control systems, turret cupolas, suspension configurations and powerpacks . At least one of these hulls

5820-425: The heavy tank program to be audited. Investigators had been unable to determine the cost of the program, which was estimated in the hundreds of millions of dollars. The report said the Army had hastened production of the tank for war in Korea despite there being no need for it there. The tank was also unsuited to the rigors of the nuclear battlefield, the report said. Following contemporary American design philosophy,

5917-433: The immediate replacement of the M48A2 as well as better quality control. Under the ARCOVE's "single, efficient producer" model, Defense Secretary Charles Erwin Wilson directed the Army to reduce the number of contractors producing each model of tank. In a new round of production bids for the M48A2, General Motors underbid Chrysler, and in September 1953 Army Secretary Robert T. Stevens awarded GM's Fisher Body division

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6014-414: The importance given to rapidly equipping combat units with new tanks precluded detailed testing and evaluation prior to its quantity production. Notable among these were the T42 , T69 and T48 projects as well as continuing to pursue further improvements to the M47. Compromise was inevitable, but not always welcomed, as General Bruce C. Clarke ironically observed: "We know exactly what we want. We want

6111-495: The lack of range, an add-on modification allowed the use of 4 external jettisonable 55 US gal (210 L) fuel drums of MOGAS (motor gasoline) that was mounted to the rear deck, extending the range to 135 mi (217 km). This proved very unpopular with tank crews and operational range remained unsatisfactory. Further ARCOVE changes included a desire for the commander to observe and operate his weapons station while remaining under armor protection. At this same time

6208-408: The left of the main gun and a .50cal M2HB mounted on the commander's cupola. The full image stereoscopic T46E1/M12 rangefinder was placed in the central section of the turret. Pilot #3 was constructed in November 1952 and used the Mod B hull and turret designs with a simplified, larger diameter hatch that was easier for the driver to operate. Also the front vision block was removable and allowed for

6305-403: The link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=T43&oldid=1211719098 " Category : Letter–number combination disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages T43 heavy tank In December 1950,

6402-401: The majority of its service life. For ease of production, many of the large components of the tank were made from cast armor. This design scheme was also much more mass efficient than traditional rolled plate armor. Despite being better protected than the T29 -series of prototypes which preceded it, the M103 was nearly 10 short tons (9.1 t; 8.9 long tons) lighter, making it competitive with

6499-413: The mid-1990s. Many M48s remain in service in countries other than the US. Most of these have been modified and their firepower, mobility and protection upgraded to increase their combat effectiveness on the modern battlefield. As of 2015, Turkey is the largest operator with over 750 units in service, Taiwan is second with approximately 500 upgraded variants, and Greece is third with 390 in service. After

6596-440: The much lighter M48 / M60 tanks, was insufficient to drive the much heavier M103. The tank was, consequently, severely underpowered and very fuel intensive. This presented a host of logistical problems for the vehicle, most prominently the extremely limited range of just 80 miles (130 km). Though this was partially corrected with the introduction of the AV-1790-2 diesel unit, the M103 would remain cumbersome and fuel-thirsty for

6693-422: The new heavy tank to supplement its M48 tanks. In Europe, the US Army fielded only one battalion of heavy tanks, from January 1958, originally assigned to the 899th Tank Battalion, later re-designated the 2d Battalion, 33d Armor . The US Army heavy armor battalion, in contrast to other armor units, was organized into four tank companies, composed of six platoons each, of which each platoon contained three M103s, for

6790-425: The new round of bidding. In September 1954 the Army awarded Chrysler an exclusive $ 160.6 million contract to restart production. In November 1955 the Army awarded American Locomotive Company a $ 73 million contract to begin producing 600 M48A2s the next year at the Schenectady Tank Plant, New York. However Alco opted to wrap up its tank business when its contract ended in July 1956. In May the Army awarded Chrysler,

6887-531: The new tank, designating the production tanks as the 90mm Gun Tank M48. The Army planned to produce some 9,000 M48s within three years of development. Chrysler Corporation became the principal producer of the tank. Expected production and teething troubles led to the creation of integrating committees to coordinate tank and component development. These Army Combat Vehicle (ARCOVE) committees included military and industrial representatives who provided early warning of defects and recommended remedies. Testing trials of

6984-617: The only bidder, a $ 119 million contract to continue production of the M48A2 at the Delaware Tank Plant. In December 1955 Chrysler took on orders initially intended for the American Locomotive after Alco opted production cutbacks to its tank program and became the only manufacturer of the tank by the end of 1956. During the ARCOVE Questionmark III conference in June 1957 it was predicted that

7081-452: The rear of the turret and in the hull. With both loaders, the maximum firing rate of the gun was five rounds per minute, owing to the design of the two-piece ammunition. Using the electrohydraulic turret traverse, the gunner could turn the turret at 18 degrees per second, with 15 degrees of elevation and 8 degrees of gun depression. The armor was made from welded rolled and cast homogeneous steel of varying thickness. US Army 7th Army wanted

7178-414: The road to obsolescence when the US Army shifted to the concept of a single main battle tank optimizing firepower, protection, and mobility in a single medium tank design. The U.S. M60 tank fulfilled the breakthrough functions of M103 heavy tank while retaining the mobility of M48 medium tanks. By that time it was years since US Army had realized Soviet heavy tanks were not as potent as suspected, and thus

7275-413: The roof of the tank turret to support the range finder on steel radial ball bearings. A parallel gun linkage between the gun trunnion and the range finder assures that the line of sight of the range finder reproduces the exact motion of the gun in elevation. A .30 caliber M1919E4 machine gun was coaxially mounted to the main gun's left and was operated by the gunner. An M12 full field optical range finder

7372-455: The taillights, newly redesigned mudguards, an updated fuel delivery system and a tank infantry phone were added. The concurrent testing of the T48 and production of the M48 was the source of widespread debate among Congressional Budget Oversight committees. The Bureau of the Budget believed that the Army was not progressing with sufficient speed in its tank modernization program and recommended

7469-581: The tank commander to aim and fire his weapon while remaining under armor protection via a remote controlled M2HB machine gun, however the commander had to open the cupola hatch and expose his head to reload or service the machine gun due to the limited headroom. These cupolas had a small rearward opening hatch and a single, non-removable vision block. They were designed by Aircraft Armaments Incorporated . Because of its smaller turret roof hatch opening those M1 cupolas retro-fitted to early production M48 Mod A turrets used an adaptor ring. The M1E1 cupola design used

7566-405: The tank commander's weapon on a pedestal, which allowed him to fire the .50 caliber (12.7 mm) M2HB machine gun from within the vehicle's turret. It used a 100-round ammunition box and could also be employed manually by the commander. However, servicing and reloading of the weapon required the tank commander to open his roof hatch and expose his head and upper torso. This remote-controllable mount

7663-571: The tank would "out-slug any land-fighting machine ever built." Like the contemporary British Conqueror , the M103 was designed to counter Soviet heavy tanks, such as the later IS-series tanks or the T-10 , if conflict with the Eastern Bloc broke out. Its long-ranged 4.7 in (120 mm) cannon was designed to destroy enemy tanks at extreme distances. Some 300 tanks were built between 1953 and 1954, initially designated T43E1. Details about

7760-627: The tank, including production plans and specifications, were tightly held. Seeking to keep the tank out of public sight, Secretary of Defense Charles E. Wilson nixed an October 1953 exhibition for the American Ordnance Association at Aberdeen Proving Ground . In May 1954, the tank was debuted publicly at a demonstration at the Newark tank plant. In 1953, the Pentagon began to reverse the Truman administration's policy of

7857-486: The top of the rear deck. There was a dual compensating idler arm at the front, and dual auxiliary track tension wheels behind the last road wheels, using the T97E2 track assembly. The drive sprocket was located at the rear of the hull. Shock absorbers were mounted at the first two and last roadwheel arms. This hull design was manufactured for the original M48 and M48A1 versions of the M48 series. Many Mod B hull designs used for

7954-472: The turret had somewhat smaller diameter hatches. The gunner was provided with an M37 .30 cal machine gun with 5,900 rounds of ammunition. During WWII and the Korean War, most tanks used a direct sighting system where the gun sights and rangefinders were slaved directly to the gun's barrel but its long range accuracy depended upon the focusing abilities of the individual gunner. There are two basic types of optical rangefinders , stereoscopic and coincidence. With

8051-408: Was a dual compensating idler arm at the front, and dual auxiliary track tension wheels behind the last road wheels, as had the preceding M46 and M47 tanks. The M48 used the new 28 in (0.71 m) wide T97E2 track assembly. It had hydraulic shock absorbers mounted on the first, second and sixth roadwheel pairs (opposite of the M46 and M47). The bow mounted machine gun and its related crew station

8148-431: Was a rifled gun firing a separate-loading round, in which the projectile was loaded into the breech, followed by a cartridge case consisting of a brass case, primer, and propellant in a fixed unit. This separate-loading system necessitated the use of two loaders. The only part of the cartridge case consumed during firing was the propellant and a plastic cap on the end of the brass cartridge case. The spent brass cartridge case

8245-515: Was capable of penetrating 221 millimetres (8.7 in) of 30-degree sloped rolled-homogeneous armor at 1,000 yards (910 m) and 196 millimetres (7.7 in) at 2,000 yards (1,800 m). It could also penetrate 124 millimetres (4.9 in) 60-degree sloped rolled-homogeneous armor at 1,000 yards (910 m) and 114 millimetres (4.5 in) at 2,000 yards (1,800 m). The commander could select from 34 rounds of either M358 Armor-Piercing Ballistic Cap Tracer Rounds or M469 HEAT shells, mounted at

8342-503: Was designated as the .50 Caliber Machine Gun Mount, M1 and designed by Chrysler Defense Engineering. By October 1954, the Army decided to amend the design of the tank by installing a cupola. During the production of M48s it was modified several times resulting in a wide mix of cupola styles among individual tanks. Afterwards it was renamed as the Cupola, Tank Commander's Caliber .50 Machine Gun, M1. The new tank commander cupola would allow

8439-588: Was dropped from consideration for use on the M48 but was further developed on the T69 tank as the 90 mm T178 gun. It was fitted with an eight-round auto-loader system mounted in an oscillating turret. ARCOVE also involved the Ordnance Department with the goal of improving the 90 mm gun and its ammunition. The Army expected difficulties in engagements with the Soviet IS-3 heavy tank , since

8536-472: Was ejected after firing. The M1A1 tank's 4.7 in (120 mm) main gun is a smooth bore firing a semi-caseless round, ejecting only a back cap of the original loaded round; the bulk of the M1A1's 4.7 in (120 mm) shell casing is consumed during firing . Ammunition for M103's M58 gun included: Existing M103 and M103A2s include: Background: History of the tank , Tank classification , Tanks in

8633-399: Was eliminated thus providing more ammunition storage for the main gun. The driver's station was moved to the front center of the hull. The steering controls were redesigned. A large aircraft-styled steering wheel (replacing the wobble stick control of the M46 and M47) and placing the transmission range selector on the floor to the driver's right. Mod A hulls had a small oval overhead hatch for

8730-430: Was envisioned to be fitted to the hull. It was also desired that a turret be constructed using this special armor. The OTAC and Carnegie Institute of Technology began development of the armor in November 1952 at Fort Belvoir VA as Project TT2-782/51. This composite armor offered protection against HEAT, HESH , and HE rounds. Its overall slow development limited its use to the T48 and was dropped from consideration in

8827-447: Was fitted with experimental silica glass composite armor panels. In conjunction with the development of the T48 project there was some discussion regarding armor. The weight of conventional armored steel needed to provide protection against the emerging large-caliber high-velocity main guns and improved APDS kinetic energy penetrators was making its continued use impractical. Composite applique armor panels made with fused silica glass

8924-735: Was fitted with the M1 cupola that enclosed the M2HB machine gun. Cupolas fitted on those tanks with early production Mod A turrets used an adapter ring. In April 1953, the Army standardized this configuration as the 90mm Gun Tank M48A1 Patton and originally applied this designation to both the early Mod A hull design and the Mod B hulls currently in series production. Between April 1952 and December 1954, nearly 7,000 M48s and M48A1s were produced, with production contracts for an additional 2,500 tanks to be built through 1956. Army units in Europe immediately received 2,120 of these early M48A1 tanks, but correction of ARCOVE defects discovered after production delayed

9021-407: Was found that the engine was underpowered, requiring replacement of engines and transmissions after only about 500 mi (800 km). In addition, the ammunition stowage was not convenient, repeated firing caused excess chamber erosion, and tracks were easily thrown. Last but not least crew safety, comfort and ability to function were impaired by poor interior arrangement. The M103 was placed on

9118-453: Was found to be prone to snagging brush. It was replaced with a T-shaped model early in production. These early M48 tanks suffered from engine, transmission, track, and suspension problems. The first production vehicles suffered from excessive oil consumption and engine failures after only 1,000 mi (1,600 km). The gasoline engine managed only 0.33 mpg US (0.14 km/L), limiting range to 75 miles (121 km). The M12/T41 rangefinder

9215-416: Was not used for production M48 tanks. It used the Mod A hull and turret designs with smaller diameter crew hatches. The driver's hatch incorporated a mechanism that dropped his three periscope heads to provide clearance for the hatch door as it swung to the right, and the driver then had to reposition the periscopes by hand once the hatch was closed again. It had 5 return rollers, 6 roadwheel pairs per side with

9312-548: Was too fragile and often broke. Army Field Forces (AFF) found these tanks to be unsuitable for combat use in Europe and was regulated to limited use by US Army CONUS units until numerous shortcomings were corrected. Furthermore, some 120 hulls were found to have insufficient hull armor protection. These were denoted as the M48C and relegated by the Continental Army Command (CONARC) for non-ballistic training use by

9409-466: Was used, the same as the M47. The tank was not fitted with any night fighting or computerized fire control systems. Some early production M48s used a Y-shaped blast deflector on the barrel and carried 53 rounds. Eight ready rounds were stored in the left side of the turret bustle for the loader, the rest were stored inside safe containers in the hull. Tank crews complained that the Y-shaped fume extractor

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