XM360
The XM360 is an American smoothbore cannon that was in development between 2002 and 2009. It was supposed to give the Mounted Combat System of the Future Combat System high firepower, comparable to a modern battle tank, but based on a platform weighing only 20 tons.
development
When the Future Combat System was defined, and with the XM1202 Mounted Combat System, a system for direct fire support was deemed necessary, the question of how to arm the vehicle was raised. After a series of investigations, General Dynamics Land Systems decided to equip the Mounted Combat System (MCS) with a 120 mm smoothbore cannon called the XM360. The development started in October 2002 as a joint effort between the US Army Project Manager for Maneuver Ammunition Systems (PM MAS), the US Army Armament Research Development and Engineering Center (ARDEC) and General Dynamics Land Systems (GDLS). General Dynamics Land Systems and ARDEC Benet Laboratories started a joint initiative called the Vehicle Dynamic Response Demonstrator (VDRD). In this, the development steps design and demonstration were fixed in time and the requirements that the weapon had to meet were specified.
In December 2003, the first shot attempts began at Aberdeen Proving Ground , which were followed by an Advanced Technology Demonstrator (ATD). The ATD was intended to demonstrate the development goals of the weapons system for direct and indirect fire, fire control, automatic loading and ammunition technology. In November 2004, shooting tests were carried out at the Aberdeen Proving Ground with the 120 mm XM360 ATD. This dragged on until the Future Combat Systems program was discontinued, and thus also the XM360 program until 2009. Most recently, the tower including the loading machine and weapon system was tested.
technology
Weapon system
The design of the weapon system was largely based on the experience that Benet Laboratories was able to gain with the 105 mm XM35 drawn barrel cannon and the development of the 120/140 mm smooth barreled XM291 Advanced Tank Cannon . The weapon was designed to be extremely lightweight in order to be able to mount the firepower of a 60-ton main battle tank on a 20-ton platform. The breech of the weapon is a compromise between the drop block lock of the Rheinmetall 120 mm L / 44 smoothbore gun and the screw lock of the XM291. The XM360 is designed with a drop block lock, which, however, has several vertical grooves and grooves to ensure a better introduction of force into the pipe holder. As a special feature, the shutter is electrically driven (600 volts direct current), with manual emergency operation. As with the XM35 / XM291, the two recoil dampers are arranged compactly on the weapon system and parallel to them, on the opposite side of the barrel, there are two gas - powered barrel retrievers . The pipe return is 25 inches (635 mm). The effective muzzle brake limits the maximum recoil force to around 378 kN.
As with the XM291, the tube is made of a composite material. For this purpose, carbon-fiber-reinforced plastic is wound onto the high-strength steel tube, which has been forged into shape . The innermost and outermost layers each consist of two ± 45 ° layers of S2 glass to prevent corrosion and damage. The layers in between consist of IM7 carbon fibers and are machine-wound onto the tube transversely to the longitudinal axis of the tube. For this purpose, prepregs are used, which are heated by a hot gas flame, then wound onto the pipe under tension and fixed with a roller. The thermoplastic polyetheretherketone (PEEK) is used as the matrix material , as this means that there is no need for expensive curing of the component in the autoclave . The weight of the gun barrel can thus be reduced from 889 kg of a pure steel barrel to 796 kg (minus 93 kg). Thanks to the slotted muzzle brake , the barrel is 5460 mm longer than the Rheinmetall cannon, despite the same caliber length of 44. Since the XM1202 was intended to use an unmanned turret, the gun barrel is not equipped with a smoke evacuator. The protective pipe cover is two-part and angular, which is intended to lower the radar and infrared signature. The rear part is fixed to the panel.
As a result of these measures, the weight of the XM360 weapon system could be drastically reduced to only 1865 kg. For comparison: Rheinmetall's 120 mm smoothbore gun, also with 44 caliber lengths, weighs 3780 kilograms. A version called the XM360E1 was still being discussed for the M1 Abrams. This version should have a reduced return, no muzzle brake and a new cover for the coaxial machine gun, and be designed for manual operation. In return, higher impulses and chamber pressures and fewer sensors should be available.
Loading machine
Although not explicitly mentioned, the pictures show that the loading machine of the XM1202 MCS was taken over by Tank Test Bed (TTB). The entire system was tested in 2009. The grenades are housed vertically upside down in a carousel in the tower cage ( Turret Basket Magazine, TBM ). The electro-hydraulic transfer unit ( Turret Transfer Unit, TTU ) is located in the rear of the tower . This tilts forwards into the tower cage for loading and extends a gripper downwards using two hydraulic arms. This grabs the desired ammunition at the rear and pulls it onto the charging cradle. The transfer piece now folds back into the horizontal. Now the hydraulic arms move forward again to attach the cartridge. These then pull back again to create space for the return pipe. If the shot is fired, the case stub is caught by the transfer piece and ejected over the rear of the turret. The autoloader can perform several functions:
- Ammunition selection via the carousel and loading of the weapon system with 12 rounds per minute.
- Automatic case ejection via the turret stern
- Removal of misfires from the weapon and ejection via the turret stern
- Relocation of floors in the carousel
- Cartridges are withdrawn from the weapon and returned to the carousel or ejected via the rear of the turret
- Ammunition of the carousel with 6 to 8 rounds per minute over the turret rear
The size of the carousel is specified as 27 shots for the MCS, and 44 cartridges for the TTB. However, the pictures of the MCS tower show that there was also space for around 40 floors.
ammunition
With the beginning of the development of the XM1202 Mounted Combat System , three types of ammunition were postulated which should be fired by his XM360 120 mm smoothbore cannon: the Advanced Kinetic Energy (AKE) projectile, the Advanced Multi-Purpose (AMP) ammunition and the mid-range Ammunition (MRM) . While the Future Combat Systems program has now been discontinued, the types of ammunition are being further developed for series production:
- Advanced Kinetic Energy (AKE): The APFSDS bullet is being developed under the designation M829E4 , and it is expected to be ready for use in 2014.
- Advanced Multi-Purpose (AMP): Multi-purpose grenade intended to replace M908 (Obstacle Reduction), M830 (HEAT), M830A1 (MPAT) and M1028 (Canister) with a type of shell. It is expected to be ready for use in 2014.
- Mid-Range Ammunition (MRM): Self-targeting projectile for indirect fire up to 12 km away. Expected to be operational in 2013.
Individual evidence
- ↑ Jane's - 120 mm XM360 smoothbore gun (United States)
- ↑ a b c ARDEC - 120 MM XM360 GUN FOR THE FUTURE COMBAT SYSTEM - TEST RESULTS & NEW TECHNOLOGY ( Memento from December 16, 2011 in the Internet Archive ) (PDF; 2.2 MB)
- ↑ a b US Army RDECOM-ARDEC Benét Laboratories - PRESTRESSED CARBON FIBER COMPOSITE OVERWRAPPED GUN TUBE
- ↑ US Army Research, Development and Engineering Command Benet Laboratories - 120 mm XM360 Primary Weapon Assembly XM1202 Mounted Combat System (MCS) of Future Combat System (FCS) ( Memento of March 11, 2012 in the Internet Archive ) (PDF; 1.7 MB )
- ↑ ARMOR March / April 1995: Ammunition Loading Systems for Future Tanks ( Memento from September 21, 2012 in the Internet Archive ) (PDF; 6.3 MB)
- ↑ PM FCS (BCT) Platform Overview - Combat Vehicles Conference ( Memento from November 28, 2012 in the Internet Archive ) (PDF; 4.0 MB)
- ↑ Precision Strike Association (Affordable Precision Munitions) ( Memento from December 1, 2012 in the Internet Archive ) (PDF; 3.5 MB)
- ↑ FAS - Future Tank Main Gun Ammunition (FTMGA) (PDF; 292 kB)