Misplaced Pages

Rheinmetall Rh-120

Article snapshot taken from Wikipedia with creative commons attribution-sharealike license. Give it a read and then ask your questions in the chat. We can research this topic together.

This is an old revision of this page, as edited by Catalan (talk | contribs) at 03:28, 12 November 2008 (→Modernization: +2 countries). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

Revision as of 03:28, 12 November 2008 by Catalan (talk | contribs) (→Modernization: +2 countries)(diff) ← Previous revision | Latest revision (diff) | Newer revision → (diff)
A Singaporean Leopard 2A4, armed with Rheinmetall's 120-millimeter (4.7 in) tank gun

The Rheinmetall 120 mm gun is a smoothbore tank gun designed and produced by the German Rheinmetall-DeTec AG company. It comes in two main variants: L44 and the L55.

Background

Prototype of the Leopard 2

The first instance of a larger Soviet tank gun was witnessed on the chassis of a modified T-55 in 1961. In 1965, the Soviet Union's T-62 made its first public appearance, armed with a 115-millimeter (4.5 in) smoothbore tank gun. The catalyst for the Soviet decision to increase the power of its tank's main armament had come when, in the early 1960s, an Iranian tank commander defected over the Soviet border in a brand-new M60 Patton tank, which was armed with the British Royal Ordnance L7 105-millimeter (4.1 in) tank gun. Despite the introduction of the T-62, in 1969 their T-64 tank was rearmed with a new 125-millimeter (4.9 in) tank gun, while in 1972 Nizhny Tagil began production of the T-72 tank, also armed with the 125-millimeter (4.9 in) tank gun. Worried about the ability of the existing NATO 105-millimeter (4.1 in) tank gun to penetrate new Soviet armor, Rheinmetall began development of a new tank gun in 1964. For example, at the fighting at Sultan Yakoub, during the 1982 Lebanon War, the Israeli government claimed to have destroyed 9 Syrian T-72s with the Merkava II main battle tank, armed with an Israeli production version of the American M68 105-millimeter (4.1 in) tank gun (which in turn was based on the British L7). Whether or not true, the Soviets test fired a number of Israeli M111 Hetz armor piercing discarding sabots at Kubinka, finding the 105-millimeter (4.1 in) round was able to perforate the T-72's glacis plate, but not its turret armor. This would later lead Israel to opt for a 120-millimeter (4.7 in) tank gun during the development process of the Merkava III main battle tank. This case is similar to the American decision to replace the M68 105-millimeter (4.1 in) tank gun with Rheinmetall's 120-millimeter (4.7 in) gun in 1976; the introduction of the T-64A had caused an uncertainty within the armor community on whether or not the new ammunition designed for the existing gun caliber could effectively deal with the new Soviet tank threat.

In 1963, Germany and the United States had already embarked on a joint–tank program, known as the MBT-70. The new tank featured a three-man crew, with the driver in the turret, an automatic loader for the main gun, a 20-millimeter (0.79 in) coaxial autocannon, an active hydropneumatic suspension and spaced armor on the glacis plate and the front turret. The new tank concept also featured an improved tank armament; this was a 152-millimeter (6.0 in) missile-launching main gun, designed to fire the MGM-51 Shillelagh anti-tank missile. However, the German Army was interested in a tank gun which could also fire conventional ammunition. Although there were attempts to modify the 152-millimeter (6.0 in) tank gun to do so, the process proved extremely difficult, and the Germans began development of the future Rheinmetall 120-millimeter (4.7 in) tank gun instead.

In 1967, the German Ministry of Defense decided to re-open a Leopard 1 improvement program, known as the Vergoldeter Leopard (Gilded Leopard), later renamed the Keiler (Wild Boar). Krauss Maffei was chosen as the contractor, and two prototypes were developed in 1969 and 1970. This program grew into the Leopard 2, and the first prototype of the new tank was delivered in 1972, equipped with a 105-millimeter (4.1 in) smoothbore main gun. Between 1972 and 1975 a total of 17 prototypes were developed. Simultaneously, the new 120-millimeter (4.7 in) tank gun's ten year development effort, which had begun in 1964, ended in 1974. Ten of the 17 turrets built were equipped with the 105-millimeter (4.1 in) smoothbore gun, while the other seven were equipped with the larger 120-millimeter (4.7 in) tank gun. Another program aimed to mount the 152-millimeter (6.0 in) missile-gun was also developed, in an attempt to save components from the MBT-70, but in 1971 the program was ended for economic reasons. Instead, the Germans opted for Rheinmetall's 120-millimeter (4.7 in) L/44 smoothbore tank gun.

Gun system

File:Korean Army K1A1 tank.jpg
Korean Army K1A1 tank armed with a nationally manufactured version of Rheinmetall's 120-millimeter (4.7 in) L/44 tank gun

With a caliber of 120 millimeters (4.7 in), and a caliber length of 44, Rheinmetall's tank gun has a length of 5.28 meters (5.77 yd). The gun's barrel weighs 1,190 kilograms (2,620 lb), and on the M1 Abrams the gun mount weighs 3,317 kilograms (7,313 lb). The bore evacuator and the gun's thermal sleeve, designed to regulate the temperature of the barrel, are fabricated out glass-reinforced plastic, while the barrel sports a chrome lining to increase barrel life. However, with recent advances in propellant technology, the average barrel life has decreased to 260 rounds, from an original barrel life of anywhere between 400–500 rounds; in some cases, barrels have had to be replaced after only 50 fired projectiles. The gun's recoil mechanism is composed of two hydraulic retarders and a hydropneumatic assembly.

Production of the German Leopard 2 and the new 120-millimeter (4.7 in) tank gun began in 1979, fulfilling an order for the German Army. Although the American M1 Abrams was originally armed with a 105-millimeter (4.1 in) main gun, the United States Army had planned to outfit the tank with a larger main gun at a later date; therefore, the tank's turret had been designed to accept a larger 120-millimeter (4.7 in) gun. The larger gun was integrated into the M1A1 Abrams, with the first vehicle coming off the production line in 1985 The gun, known as the M256, was based on Rheinmetall's 120-millimeter (4.7 in) L/44 tank gun, although manufactured at Watervliet Arsenal and modified to increase the resistance of the barrels to fracture and fatigue. In the 1980s, the Israeli Army began to develop the Merkava III main battle tank; this tank would introduce a new 120-millimeter (4.7 in) tank gun, to replace the M68 105-millimeter (4.1 in) gun on the Merkava I and Merkava II. Originally planned to be a licensed production version of the American M256, the gun was modified and manufactured in Israel; the Israeli gun retains the inner geometry of the barrel to allow commonality with German and American ammunition. Named the MG251, a version of the gun is also in production to arm the Sabra modification of Turkish M60 Patton tanks. An improved version of the Israeli tank gun was introduced with the Merkava IV, giving the gun the ability to survive higher barrel pressures, which in turn allows increased muzzle velocity for kinetic energy penetrators. Other tanks armed with licensed produced versions of Rheinmetall's gun include Japan's Type 90 and South Korea's K1A1.

Due to tank sales, Rheinmetall's tank gun has also proliferated to other nations. For example, the Leopard 2, armed with the 44 caliber long gun, has been sold to the Netherlands, Switzerland, Sweden, Spain, Austria, Denmark, amongst others. Egypt manufactured 700–800 M1A1 Abrams by 2005, while in 2008 Egypt requested permission to build another 125 tanks; the M256 main guns, arming the tanks, were manufactured by General Dynamics. The M1A1 has also been exported to Australia, while the M1A2 Abrams has been exported to Saudi Arabia and Kuwait.

Use of Rheinmetall's L/44 Tank Gun
Tank Designer Nation Gun Proliferation
Leopard 2 Krauss-Maffei  Germany Rheinmetall 120-millimeter (4.7 in) L/44 Austria, Chile, Denmark, Netherlands, Spain, Sweden, Switzerland
M1 Abrams Chrysler (now owned by General Dynamics Land Systems)  USA M256 Australia, Egypt, Kuwait, Saudi Arabia
Merkava III & IV Israel Military Industries  Israel MG251 -
K1A1 Hyundai Rotem  South Korea M256 -
Type 90 Mitsubishi Heavy Industries  Japan Rheinmetall 120-millimeter (4.7 in) L/44 -
Sabra Israel Military Industries  Israel/ Turkey MG251 Turkey

Modernization

Two Leopard 2A6 of the German Army with L55

The appearance of new Soviet tanks during the late 1970s and early 1980s, such as the T-80B, demanded the development of new technologies and weapons to counter the threat posed to Western armor. Apart from increased firepower, the T-80B also featured a new composite ceramic armor. The T-72 also went through a modernization program, in an attempt to bring it up to the standards of the T-80B. In 1985, a new version entered production, known as the T-72B, showcasing a new laminate armor protection system. The turret armor of the T-72B surpassed the T-80B's in protection, and was designed primarily to defeat anti-tank missiles.

The German government began the development of the Leopard 3, although this was canceled after the fall of the Soviet Union. On 29 October 1991, the governments of Switzerland, Netherlands and Germany agreed to cooperate in the development of a modernization program for the Leopard 2. Part of this program included the introduction of a longer 120-millimeter (4.7 in) tank gun, a cheaper alternative to a brand new tank gun. The new barrel is 55 calibers long, increasing the length by 1.30 meters (1.42 yd), increasing the maximum range of the gun by an estimated 1,500 meters (1,600 yd). Although the gun is longer, allowing for a higher peak pressure from the propellant, the geometry remains the same, allowing the gun to fire the same ammunition as that fired from the shorter caliber version of the cannon. The longer barrel also allows ammunition to attain higher velocities; for example, with new kinetic energy penetrators ammunition can reach velocities of around 1,750 meters per second (5,700 ft/s). The new barrel weighs 1,347 kilograms (2,970 lb).

The longer tank gun has been retrofitted into the Leopard 2, into a model known as the Leopard 2A6. Both the Spanish Leopard 2E and the Greek Leopard 2HEL, as derivatives of the Leopard 2A6, also use the 55 caliber long tank gun. Through export, the Leopard 2A6 and its longer main gun is also employed by the Canadian Army, and the Netherlands has also upgraded part of its original fleet of Leopard 2s with the more powerful armament. The new South Korean K2 main battle tank also employs the German 120-millimeter (4.7 in) L/55 tank gun. The British Army has also tested Rheinmetall's longer gun, possibly looking to replace the current L30A1 120-millimeter (4.7 in) rifled main gun on the Challenger 2. Two Challenger 2s were modified to undergo firing trials.

Use of Rheinmetall's L/55 Tank Gun
Tank Designer Nation Gun Proliferation
Leopard 2A6 Krauss-Maffei  Germany Rheinmetall 120-millimeter (4.7 in) L/55 Canada, Greece, Netherlands, Portugal, Spain
K2 Hyundai  South Korea Rheinmetall 120-millimeter (4.7 in) L/55 -

Ammunition

The American M829 armor piercing sabot

A variety of rounds have been developed for Rheinmetall's tank gun, around the world. For example, a long line of armor piercing discarding sabots was developed by Rheinmetall. Originally, the Leopard 2 was outfitted with the DM-23 kinetic energy penetrator, based on the Israeli M111 Hetz. The DM23 was eventually replaced by the DM33, which was also adopted by Japan, Italy, Netherlands and Switzerland. The DM43 is a further development of this round, co-developed between Germany and France. The United States also adopted the round and manufactured it as the M829. The DM-33 has a three-part aluminum sabot and a two-part tungsten penetrator, and is said to be able to penetrate 50 millimeters (2.0 in) of steel armor at a range of 2,000 meters (2,200 yd). The introduction of the longer barrel came hand in hand with the introduction of a new kinetic energy penetrator, the DM53. With a muzzle velocity of 1,750 meters per second (5,700 ft/s), the projectile has an engagement range of up to 4,000 meters (4,400 yd). A further development, called the DM63, improved upon the round by introducing a new temperature independent propellant, which allows the propellant to have a constant pattern of expansion between ambient temperatures (inside the gun barrel) of anywhere between −47 °C (−53 °F) and +71 °C (160 °F). Fired from the long barrel L/55, the round has a muzzle velocity of 1,650 meters per second (5,400 ft/s). The new propellant powders, known as surface coated double base (SCDB) propellants, allow the DM63 to be used in a wide variety of climates without a negative impact on the projectile's performance. Apart from Germany, the new ammunition has also been accepted into service with the Dutch and Swiss armies.

The United States has also developed a number of kinetic energy penetrators, based on the M289. An immediate improvement, known as the M829A1, was dubbed the "Silver Bullet" after its combat performance, during the Gulf War, against Iraqi T-55s, T-62s and T-72s. The M829 series centers around the depleted uranium penetrator, designed to penetrate enemy armor through kinetic energy and to shatter inside the turret, thereby damaging as much as possible within the confinement of the tank. In 1998, the United States military introduced the M829A2, which has an improved depleted uranium penetrator. In 2002, production of the M829A3 began, which is said to be able to defeat the latest versions of Russian explosive reactive armor.

Both Germany and the United States have developed a number of other rounds. These include the German DM12 multipurpose anti-tank projectile (MPAT), based on the technology in a high explosive anti-tank warhead. However, it's been found that the DM12's armor killing abilities are limited by the lack of blast and fragmentation effects, and that the round is less valuable against lightly armored targets. The United States also has a MPAT type projectile, known as the M830. This was later developed into the M830A1 which allows the M1 Abrams to use the round against helicopters. The M1 Abrams can also make use of the M1028 canister round, which is an antipersonnel munition, packed with over 1,000 tungsten balls.

Combat history

Notes

  1. Norman, p. 14
  2. Zaloga (1979), p. 20
  3. ^ Zaloga (2004), p. 5
  4. Zaloga (2004), p. 7
  5. ^ Jane's Armour & Artillery, Rheinmetall 120 mm L44 smoothbore gun (Germany), accessed 6 November 2008
  6. Warford (2006), pp. 23–24
  7. Warford (2006), p. 24
  8. Katz (1997), 38
  9. Green (2005), 32–33
  10. Hilmes (2001), p. 17
  11. Zaloga (1982), p. 19
  12. McNaugher (1981), p. vi
  13. Jerchel (1998), p. 5
  14. Hilmes (2001), p. 18
  15. Jerchel (1998), p. 6
  16. Jerchel (1998), pp. 6–7
  17. Jerchel (1998), p. 7
  18. Rheinmetall Defense, 120 mm L44 Tank Gun, accessed 9 November 2008; barrel length can be found by multiplying the caliber length by the caliber diameter.
  19. ^ Maxwell (2002), p. 82
  20. Green (2005), p. 61
  21. Burton (2004), pp. 51–52
  22. Jerchel (1998), p. 11
  23. ^ Green (1992), p. 56
  24. Chait (2005), p. 12
  25. Green (2005), pp. 24–29
  26. Chait (2005), pp. 12–13
  27. Katz (1997), pp. 38–39
  28. Katz (1997), p. 38
  29. Gelbart (2004), p. 35
  30. Hilmes (2007), p. 88
  31. Maxwell (2003), p. 15
  32. Gelbart (2004), p. 39
  33. Eshel (2003), p. 45
  34. Bolté (1997), p. 25
  35. Clemens (1999), p. 15
  36. Jerchel (1998), pp. 36–42
  37. Green (2005), p. 25
  38. Defense Industry Daily, Egypt: $889M Request for 125 M1A1 Tanks, accessed 9 November 2008
  39. Jane's Defense Weekly, Australia prepares for M1A1s, accessed 9 November 2008
  40. Green (2005), p. 34
  41. Jerchel (1998), p. 24
  42. Baryatinskiy (2006), pp. 23–25
  43. Baryatinskiy (2006), p. 14
  44. Zaloga (1993), p. 10
  45. Jerchel (1998), p. 33–34
  46. Jerchel (1998), p. 34
  47. ^ Hilmes (2004), p. 76
  48. Jane's, Rheinmetall 120 mm L55 smoothbore gun (Germany), accessed 10 November 2008
  49. Rheinmetall Defence, 120 mm L55 Tank Gun, accessed 10 November 2008
  50. Candil (2007), p. 66
  51. Defense Industry Daily, Tanks for the Lesson: Leopards, too, for Canada, accessed 10 November 2008
  52. Jane's, ROTEM K2 MBT (Korea, South), accessed 10 November 2008
  53. Rheinmetall Defence, Rheinmetall 120 mm smoothbore technology for Britain's Challenger, accessed 10 November 2008
  54. Hilmes (2007), p. 88
  55. ^ Jerchel (1998), p. 22
  56. Jane's, 105 mm M111 IMI APFSDS-T round (Israel), Tank and anti-tank guns, accessed 11 November 2008
  57. Jane's, 120 mm DM 33A1 and DM 43A1 APFSDS-T rounds (Germany), accessed 11 November 2008
  58. Eshel (2005), p. 96
  59. Eshel (2005), pp. 96–98
  60. Hilmes (2007), p. 93
  61. Jane's, 120 mm DM53 and DM63 LKE II APFSDS-T round (Germany), accessed 11 November 2008
  62. Green (2005), p. 68
  63. Green (1992), p. 74
  64. Green (1992), pp. 76–77
  65. Green (2005), p. 69
  66. Green (2005), p. 70
  67. Eshel (2005), p. 98
  68. Green (2005), p. 71
  69. Fogg (1994), p. 12
  70. Green (2005), p. 72

References

  • Baryatinskiy, Mikhail (2007). Main Battle Tank T-80. Surrey, United Kingdom: Ian Allen. p. 96. ISBN 0 7110 3238 6. {{cite book}}: Cite has empty unknown parameter: |coauthors= (help)
  • Bolté, Philip L. (1 January 1997). "Japanese Armored Vehicle Development". ARMOR. Fort Knox, KY: U.S. Armor Center. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  • Burton, Larry (1 January 2004). "Army Targets Age Old Problems with New Gun Barrel Technologies". AMPTIAC Quaterly. 8 (4). Rome, New York: Advanced Materials and Processes Technology Information Analysis Center. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  • Candil, Antonio (1 February 2007). "The Spanish Leopard 2E: A Magnificent Tool". Military Technology. Mönch Editorial Group: 2.
  • Chait, Richard (1 December 2005). "Critical Technology Events in the Development of the M1 Abrams". Center for Technology and National Security Policy. {{cite journal}}: Cite journal requires |journal= (help); Unknown parameter |coauthors= ignored (|author= suggested) (help)
  • Clemens, Jon (1 July 1999). "Tank Assessment Survey Ranks Leopard 2A6 Tops, With the M1A1 the Runner-up". ARMOR. Fort Knox, KY: U.S. Armor Center.
  • Dunstan, Simon (2006). Challenger 2 Main Battle Tank 1987-2006. Oxford, United Kingdom: Osprey. p. 48. ISBN 1 84176 815 4. {{cite book}}: Cite has empty unknown parameter: |coauthors= (help)
  • Eshel, David (1 January 2003). "The Merkava Mk 4 - Israel's Newest MBT Enters Service". ARMOR. Fort Knox, KY: U.S. Armor Center.
  • Eshel, Tamir (1 February 2005). "Improving the Leopard Firepower: More Potent Ammunition Prepares the Leopard to Face a Wide Spectrum of Missions". Military Technology. Mönch Editorial Group.
  • Fogg, William (1 May 1994). "The New MPAT Round". ARMOR. Fort Knox, KY: U.S. Armor Center. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  • Gelbart, Marsh (2008). Modern Israeli Tanks and Infantry Carriers 1985-2004. Oxford, United Kingdom: Osprey. p. 48. ISBN 1 84176 579 1. {{cite book}}: Cite has empty unknown parameter: |coauthors= (help)
  • Green, Michael (2005). M1 Abrams At War. St. Paul, MN: Zenith Press. p. 127. ISBN 0-7603-2153-1. {{cite book}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  • Green, Michael (1992). M1 Abrams Main Battle Tank: The Combat and Development History of the General Dynamics M1 and M1A1 Tanks. Osceola, WI: Motorbooks International. p. 96. ISBN 0 87938 597 9. {{cite book}}: Cite has empty unknown parameter: |coauthors= (help)
  • Hilmes, Rolf (1 December 2004). "Arming Future MBTs - Some Considerations". Military Technology. Mönsch.
  • Hilmes, Rolf (1 March 2007). "Development Trends in Tank Armament". Military Technology. Mönsch.
  • Jerchel, Michael (1998). Leopard 2 Main Battle Tank 1979-1998. Oxford, United Kingdom: Osprey. p. 48. ISBN 1 85532 691 4. {{cite book}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  • Katz, Sam (1997). Merkava Main Battle Tank MKs I, II & III. Oxford, United Kingdom: Osprey. p. 48. ISBN 1 85532 643 4. {{cite book}}: Cite has empty unknown parameter: |coauthors= (help)
  • Lathrop, Richard (2003). M60 Main Battle Tank 1960-91. Oxford, United Kingdom: Osprey. p. 48. ISBN 1 84176 551 1. {{cite book}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  • Maxwell, David (1 June 2002). "New Tanks for the Old, Part II: Tank Top Upgrades". Armada International. 0252-9793.
  • Maxwell, David (1 February 2003). "Try a 120 For Size". Armada International. 0252-9793.
  • Norman, Michael. Soviet Mediums T44, T54, T55 & T62. Berkshire, United Kingdom: Profile Publications Ltd. {{cite book}}: Cite has empty unknown parameter: |coauthors= (help)
  • Simpkin, Richard E. (1979). Tank Warfare: An analysis of Soviet and NATO tank philosophy. London, United Kingdom: Brassey's. p. 232. ISBN 0 904609 25 1. {{cite book}}: Cite has empty unknown parameter: |coauthors= (help)
  • Warford, James M. (1 September 2006). "The Secret Testing of Israeli M111 "Hetz" Ammunition: A Model of Failed Commander's Responsibility". ARMOR. Fort Knox, KY: U.S. Armor Center.
  • Zaloga, Steven J. (1982). Modern American Armor: Combat Vehicles of the United States Army Today. New York City, New York: Arms and Armour Press. p. 88. ISBN 0-85368-248-8. {{cite book}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  • Zaloga, Steven J. (1979). Modern Soviet Armor: Combat Vehicles of the USSR and Warsaw Pact Today. Edinburg, United Kingdom: Prentice Hall. p. 88. ISBN 0-13597-856-4. {{cite book}}: Cite has empty unknown parameter: |coauthors= (help)
  • Zaloga, Steven J. (2004). T-54 and T-55 Main Battle Tanks 1944-2004. Oxford, United Kingdom: Osprey. p. 48. ISBN 1 84176 792 1. {{cite book}}: Cite has empty unknown parameter: |coauthors= (help)
  • Zaloga, Steven J. (1993). T-72 Main Battle Tank 1974-93. Oxford, United Kingdom: Osprey. p. 48. ISBN 1 85532 338 9. {{cite book}}: Cite has empty unknown parameter: |coauthors= (help)
  • Zaloga, Steven J. (1999). The M47 and M48 Patton Tanks. Oxford, United Kingdom: Osprey. p. 48. ISBN 1 85532 825 9. {{cite book}}: Cite has empty unknown parameter: |coauthors= (help)
Categories: