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52-604: During the 1980s, the U.S. Marine Corps began looking for a light armored vehicle to give their divisions greater mobility. They chose the Light Armored Vehicle design from General Motors Diesel . The LAV-25 was partially based on the 6x6 Armoured Vehicle General Purpose (LAV I) of the Canadian Army that was also produced by General Motors Diesel. It entered service with the Marines in 1983. The U.S. Army

104-439: A bullet / slug or a flechette -like projectile (such as a kinetic energy penetrator ), and keep it aligned in the center of the barrel when fired. It allows a narrower projectile with high sectional density to be fired through a barrel of much larger bore diameter with maximal accelerative transfer of kinetic energy . After leaving the muzzle , the sabot typically separates from the projectile in flight, diverting only

156-801: A 200-metre spool of cable. When first purchased, the Coyote was designated for service with both the Regular Force and Reserve Force, with the Mast variants earmarked for the Regular units and the Remotes designated for the Reserves. Shortly after taking delivery of the vehicles, but before they were assigned to the Reserve units, all Coyotes were reassigned to the Regular Force. Since the introduction of

208-409: A bullet requires at least 1 turn in 7 inch twist, (1:7 rifling), in 5.56mm, it will also require at least 1:7 rifling when saboted in 7.62mm. However, larger caliber commercial rifles generally don't need such fast twist rates; 1:10 being a readily available standard in 7.62mm. As a result, the twist rate of the larger barrel will dictate which smaller bullets can be fired with sufficient stability out of

260-414: A form of spindle sabot. Shotgun slugs often use a cast plastic sabot similar to the spindle sabot. Shotgun sabots in general extend the full length of the projectile and are designed to be used more effectively in rifled barrels. A ring sabot uses the rear fins on a long rod projectile to help center the projectile and ride the bore, and the multi-petal sabot forms only a single bulkhead ring around

312-411: A gun barrel of equal diameter to achieve high muzzle velocity. The physics of interior ballistics demonstrates why the use of a sabot is advantageous to achieve higher muzzle velocity with an arrow-type projectile. Propellant gasses generate high pressure, and the larger the base area that pressure acts upon the greater the net force on that surface. Force (pressure times area) provides an acceleration to

364-538: A lower drag, smaller diameter and lighter bullet, successful saboted projectile design has to include the resulting bullet stability characteristics. For example, simply inserting a commercially available 5.56mm (.224) bullet into a sabot that will fire it from a commercially available 7.62mm (.300) barrel may result in that 5.56mm bullet failing to achieve sufficient gyroscopic stability to fly accurately without tumbling. To achieve gyroscopic stability of longer bullets in smaller diameter requires faster rifling. Therefore, if

416-399: A new facility. General Motors Diesel selected a site on the outskirts of London, Ontario , for this plant. It opened in 1950, eventually expanding several times to 208 acres (842,000 m ) and branching out into building transit buses, earth movers ( Terex 1965-1980) and military vehicles built at adjacent facilities. Originally designed to produce one unit per day, it took some time for

468-646: A number of domestic emergency response incidents. The Coyote is currently being retired and is being replaced by a mix of Tactical Armoured Patrol Vehicles and LAV 6 armoured vehicles. General Motors Diesel General Motors Diesel was a railway diesel locomotive manufacturer located in London, Ontario , Canada. It was established in 1949 as the Canadian subsidiary of the Electro-Motive Diesel division of General Motors (EMD). In 1969 it

520-506: A projectile, providing both structural support and obturation. Upon firing, when the sabot and projectile leave the muzzle of the gun, centrifugal force from the rotation of the projectile, due to barrel rifling, opens up the segments surrounding the projectile, rapidly presenting more surface area to air pressure, quickly releasing it. Although the use of cup sabots of various complexity are popular with rifle ammunition hand-loaders, in order to achieve significantly higher muzzle velocity with

572-430: A rear section which both centers the projectile, provides a structural "bulkhead", and seals propellant gases with an obturator ring around the outside diameter. Spindle sabots are the standard type used in modern large caliber armor-piercing ammunition. Three-petal spindle-type sabots are shown in the illustrations at the right of this paragraph. The "double-ramp" and "saddle-back" sabots used on modern APFSDS ammunition are

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624-613: A sabot. In this example, using 1:10 rifling in 7.62mm restricts saboting to 5.56mm bullets that require 1:10 twist or slower, and this requirement will tend to restrict saboting to the shorter (and lighter) 5.56mm bullets. A base sabot has a one piece base which supports the bottom of the projectile, and separate pieces that surround the sides of the projectile and center it. The base sabot can have better and cleaner sabot/projectile separation than cup or expanding cup sabots for small arms ammunition, but may be more expensive to manufacture and assemble. In larger caliber APDS ammunition, based on

676-939: A similar purpose for the American Locomotive Company (ALCO) and the Canadian Locomotive Company (CLC) in Kingston served a similar purpose for Baldwin Locomotive Works . MLW and CLC also produced steam and diesel engines of their own designs. The growing market for diesels in Canada meant it became worthwhile to build facilities in Canada to avoid import duties. While MLW and CLC both utilized existing steam locomotive erecting shops in Montreal and Kingston, respectively; General Motors, never having built steam locomotives, required

728-418: A sophisticated suite of electronic surveillance equipment including radar , video , and infrared surveillance night vision devices . The mast variant has this equipment mounted on a 10-metre telescoping mast that can be extended to raise the surveillance suite out from behind cover. The remote variant of the Coyote has its surveillance suite mounted on two short tripods, which crew can deploy remotely using

780-493: A successful joint venture company between General Dynamics Land Systems and GM Defense (the "GM-GDLS Defense Group Ltd") with the award of the US Army Stryker contract, the defense side of the Canadian operations was sold to General Dynamics in 2003. On April 4, 2005, GM sold its EMD subsidiary with its London and LaGrange operations to a partnership between Greenbriar Equity Group and Berkshire Partners . The company

832-485: A very small portion of the overall kinetic energy. The sabot component in projectile design is the relatively thin, tough and deformable seal known as a driving band or obturation ring needed to trap propellant gases behind a projectile, and also keep the projectile centered in the barrel, when the outer shell of the projectile is only slightly smaller in diameter than the caliber of the barrel. Driving bands and obturators are used to seal these full-bore projectiles in

884-527: Is also equipped with grenade dischargers that can be loaded with smoke and fragmentation grenades. The Coyote is powered by a Detroit Diesel 6V53T engine developing 400 horsepower (300 kW), and can reach speeds of 100 kilometres per hour (62 mph) (on road). The Coyote has a maximum road range of 660 kilometres (410 mi). It uses a larger wheel than initially used on the Bison and AVGP (these vehicles were later retrofitted with this wheel). Compared to

936-419: Is seated in the front-left of the crew compartment. The commander has a slightly raised position directly behind the driver with access to his own hatch and mounted machine gun. The engine is to the right of the crew compartment. The Canadian Forces began upgrading the Bison between 2002 and 2008. The upgrades include improved engine power, new torsion bars , fittings for add-on armour, air conditioning , and

988-662: The Invasion of Panama in 1989 and continued service in the Gulf War , Iraq War , and the War in Afghanistan . A USMC light-armored reconnaissance battalion includes 56 LAV-25s, 16 LAV-ATs, 12 LAV-Ls, 8 LAV-Ms, 4 LAV-Rs, 4 LAV-C2s, and an unknown number of LAV-MEWSS vehicles. The Bison is an armoured vehicle based on the 8x8 LAV-25 platform and was originally designed as an armoured personnel carrier. Entering service in 1990, it

1040-543: The M829 series of anti-tank projectiles). Sabot-type shotgun slugs were marketed in the United States from about 1985, and became legal for hunting in most U.S. states. When used with a rifled slug barrel , they are very much more accurate than normal shotgun slugs. A cup sabot supports the base and rear end of a projectile, and the cup material alone can provide both structural support and barrel obturation. When

1092-660: The "Diesel Division of General Motors of Canada Ltd." on February 1, 1969, in a consolidation of all Canadian properties. Once dominant in North American diesel locomotive production having seen Baldwin, Fairbanks-Morse, Lima-Hamilton , Alco, MLW and CLC all fall by the wayside in the railway market, General Motors fell under intense competition from General Electric (GE). During the 1950s GE expanded beyond its early production of small locomotives, much of it for small and medium size industries, into large mainline road locomotives for Class I railroads . With excess capacity at

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1144-521: The "saddle-back" and "double-ramp" sabot was performed by the US Army Ballistics Research Laboratory during the development and improvement of modern 105mm and 120mm kinetic energy APFSDS penetrators and published in 1978, permitted by the significant advancement in the computerized finite element method in structural mechanics at that time; and now represents the existing fielded technology standard. (See for example

1196-610: The 1930s into the 1940s the largest market for diesel-electric locomotives was for switchers such as the ALCO S-2 and the EMD NW2 . Tariffs protected Canadian manufacturers against imported goods, thus many companies wanting to do business in Canada set up controlled or wholly owned subsidiaries in Canada. General Motors Diesel, Ltd., was EMD's subsidiary organized for that purpose. Montreal Locomotive Works (MLW) in Montreal served

1248-483: The Australian ASLAV . The Coyote mounts a 25×137mm M242 Bushmaster chain gun and two 7.62×51mm NATO C6 general purpose machine guns . One of the machine guns is mounted coaxial to the main gun while the other is pintle-mounted in front of the crew commander's hatch. The main gun is equipped with dual ammunition feeds that allow for separate weapons effects, selectable by the gunner/crew commander;

1300-615: The Coyote to the Canadian Armed Forces, the vehicle has served national interest domestically and abroad. The Coyote served during the United Nations/ NATO missions in Bosnia and Herzegovina , Macedonia , Kosovo , and in Afghanistan. Domestically, it has been deployed during "Operation Grizzly" to Kananaskis to secure the 28th G8 summit , the 36th G8 summit , and the 2010 G-20 Toronto summit , in addition to

1352-534: The London operation following the peak demand years of the 1950s, GMC Truck and Coach Division used it for production of heavy road vehicles such as buses. The plant was also used for production of construction equipment and light armored vehicles under contract. EMD moved all locomotive construction to London in 1991, after which the London plant supplied US customers under the Free Trade agreement between Canada and

1404-489: The United States. Some primary equipment manufacturing, such as engines, generators, and traction motors, remained at EMD's LaGrange, Illinois facility. Meanwhile, locomotives were exported to Argentina, Bengal, Brazil, Ceylon, Liberia, Sweden, New Zealand; Norway and Pakistan. In the 2000s, GM reorganized the Canadian Diesel Division holdings and separated a portion out under the name "GM Defense". After

1456-734: The VRS respirator system for NBC defence. The Bison's rail mount system allows it to be adapted to a variety of roles without any major modifications. Bisons used by the Canadian Forces have been adapted for use as armoured personnel carriers (original configuration, mostly replaced in this role by the LAV III ), 81mm mortar carriers, ambulances (32), Mobile Repair Team (MRT) vehicles (32), Armoured recovery vehicles (32), electronic warfare vehicles (25), and NBC reconnaissance vehicles (4). The Coyote has been in Canadian service from 1996 and

1508-457: The barrel because of manufacturing tolerances; there always exists some gap between the projectile outer diameter and the barrel inner diameter, usually a few thousandths of an inch; enough of a gap for high pressure gasses to slip by during firing. Driving bands and obturator rings are made from material that will deform and seal the barrel as the projectile is forced from the chamber into the barrel. Sabots use driving bands and obturators, because

1560-405: The barrel, giving a larger surface area for propellant gasses to act upon than just the base of the smaller flight projectile. Efficient aerodynamic design of a flight projectile does not always accommodate efficient interior ballistic design to achieve high muzzle velocity. This is especially true for arrow-type projectiles, which are long and thin for low drag efficiency, but too thin to shoot from

1612-620: The cartridge case, an obturator or driving band. When the projectile is fired, the sabot blocks the gas, provides significant structural support against launch acceleration, and carries the projectile down the barrel. When the sabot reaches the end of the barrel, the shock of hitting still air pulls the parts of the sabot away from the projectile, allowing the projectile to continue in flight. Modern sabots are made from high strength aluminum and graphite fiber reinforced epoxy. They are used primarily to fire long rods of very dense materials, such as tungsten heavy alloy and depleted uranium. (see for example

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1664-432: The cup, expanding cup, and base sabot concepts, significantly more complex assemblies are required. A spindle sabot uses a set of at least two and upwards of four matched longitudinal rings or "petals" which have a center section in contact with a long arrow-type projectile; a front section or "bore-rider" which centers that projectile in the barrel and provides an air scoop to assist in sabot separation upon muzzle exit, and

1716-507: The development of the M829 series of anti-tank projectiles beginning with the base model M829 in the early 1980s, to the 2016 M829A4 model, employing ever longer "double-ramp" sabots). Upon muzzle exit, the sabot is discarded, and the smaller flight projectile flies to the target with less drag resistance than a full-bore projectile. In this manner, very high velocity and slender, low drag projectiles can be fired more efficiently, (see external ballistics and terminal ballistics ). Nevertheless,

1768-483: The first order (C-100) received, which was from Canadian Pacific for ten model FP7A 1,500 hp (1100 kW) A units of the "covered wagon" style of carbody. The two orders were on the shop floor under construction at the same time and it was TH&B 71 which was completed first and delivered on August 25 along with 72. Pairs of A units were delivered commencing with CP numbers 4028 and 4029 on September 14 and continuing until November 11. TH&B 71 cost $ 191,712 at

1820-417: The higher initial costs and lower reliability of early diesel locomotives. The benefit of diesels was largely their reduced operating costs compared to steam, but they had to be kept going to pay for themselves. Increased use was key to their cost benefits. The greatest savings were to be had in yard service, where switching often meant idling that maximized the efficiency advantages of diesel over steam. Through

1872-548: The later LAV-III family of vehicles, the Coyote is smaller, uses smaller wheels and tires, has a "sharp" rather than "rounded" nose profile, and has a smaller, oval driver's hatch. Like the LAV-III, the Coyote can be fitted with additional ceramic bolt-on armour panels for increased protection. The Coyote can be transported on a Hercules C-130 plane but the turret needs first to be removed. Coyotes come in three variants: Command, Mast, and Remote. The Mast and Remote variants have

1924-763: The mass of the projectile. Therefore, for a given pressure and barrel diameter, a lighter projectile can be driven from a barrel to a higher muzzle velocity than a heavier projectile. However, a lighter projectile may not fit in the barrel, because it is too thin. To make up this difference in diameter, a properly designed sabot provides less parasitic mass than if the flight projectile were made full-bore, in particular providing dramatic improvement in muzzle velocity for APDS ( Armor-piercing discarding sabot ) and APFSDS ( Armor-piercing fin-stabilized discarding sabot ) ammunition. Seminal research on two important sabot configurations for long rod penetrators used in APFSDS ammunition, namely

1976-415: The plant facility. HCL Logistics moved into the plant space after consolidating their London operations and is partner with General Dynamics Land Systems in the same site. Sabot (firearms) A sabot ( UK : / s æ ˈ b oʊ , ˈ s æ b oʊ / , US : / ˈ s eɪ b oʊ / ) is a supportive device used in firearm / artillery ammunitions to fit/patch around a projectile , such as

2028-428: The projectile near the front, with an obturator sealing gases from escaping past it, and centering the front of the projectile. The former Soviet Union favored armor-piercing sabot projectiles using ring sabots, which performed acceptably for that era, manufactured from high strength steel for both the long rod penetrator and ring sabot. The strength of the steel ring was sufficient to withstand launch accelerations without

2080-401: The sabot and projectile exit the muzzle of the gun, air pressure alone on the sabot forces the sabot to release the projectile. Cup sabots are found typically in small arms ammunition, smooth-bore shotgun and smooth-bore muzzleloader projectiles. Used typically in rifled small arms (SLAP, shotguns, and muzzleloaders), an expanding cup sabot has a one piece sabot surrounding the base and sides of

2132-427: The same manufacturing tolerance issues exist when sealing the saboted projectile in the barrel, but the sabot itself is a more substantial structural component of the in-bore projectile configuration. Refer to the two armor-piercing fin-stabilized discarding sabot ( APFSDS ) pictures to see the substantial material nature of a sabot to fill the bore diameter around the sub-caliber arrow-type flight projectile, compared to

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2184-408: The standard load is a belt of armour-piercing sabot rounds and a belt of HE-T explosive/fragmentation rounds. The main gun and coax machine gun are 2-axis stabilized. The turret is equipped with a laser rangefinder, but no ballistic computer; elevation and lead corrections are applied manually by the gunner using multi-stadia reticules in the day, thermal, and image intensification sights. The turret

2236-521: The time. For comparison, Alco 1,000 hp (750 kW) yard switchers built in Schenectady , New York cost $ 115,000 including import duty. GMD built units for export, a significant amount of business supported by government grants to foreign countries. GMD also built some experimental diesel-hydraulic locomotives and straight electric units as well, although neither were more than a tiny percentage of production. General Motors Diesel Ltd. became

2288-431: The very small gap sealed by a driving band or obturator to mitigate what is known classically as windage . More detailed cutaways of the internal structural complexity of advanced APFSDS saboted long rod penetrator projectiles can be found in #External links . The function of a sabot is to provide a larger bulkhead structure that fills the entire bore area between an intentionally designed sub-caliber flight projectile and

2340-454: The volume of orders to reach this level. Plant capacity was later expanded to one-and-a-half units per day. By comparison, La Grange, as the US plant was referred to, eventually could produce six units per day. The first diesel locomotive built was Toronto, Hamilton & Buffalo Railway (TH&B) number 71, one of four model GP7 1,500 hp (1100 kW) road switchers. It was however, not

2392-834: The weight of the sabot represents parasitic mass that must also be accelerated to muzzle velocity, but does not contribute to the terminal ballistics of the flight projectile. For this reason, great emphasis is placed on selecting strong yet lightweight structural materials for the sabot, and configuring the sabot geometry to efficiently employ these parasitic materials at minimum weight penalty. Made of some lightweight material (usually high strength plastic in small caliber rifles, (see SLAP Saboted light armor penetrator ), shotguns and muzzle loader ammunition; aluminium, steel, and carbon fiber reinforced plastic for modern anti-tank kinetic energy ammunition; and, in classic times, wood or papier-mâché – in muzzle loading cannons). The sabot usually consists of several longitudinal pieces held in place by

2444-607: Was acquired for use in the light reconnaissance (scout) role, although was also initially used as an armoured fighting vehicle in the role of medium tank trainer within armoured squadrons in the same way as the Armoured Vehicle General Purpose (AVGP) it replaced. In service since 1996, the Coyote is a later generation of the LAV-25 and is of the same family and similar generation as the Bison APC and

2496-490: Was closed by EMD's new owner Progress Rail in 2012, with EMD's production remaining in LaGrange, Illinois and Muncie , Indiana . Diesel-electric locomotives were built in Canada beginning in 1928. The earliest diesels were custom built one-of-a-kind designs such as Canadian Nationals numbers 9000 and 9001 and Canadian Pacific number 7000. After these unique locomotives, steam remained in favor for road service owing to

2548-576: Was interested in these vehicles at the time but did not order any (however they did later adopt similar vehicles with the introduction of the Stryker family). The Army did, however, borrow at least a dozen LAV-25s for use by the 82nd Airborne Division , 3-73rd Armor for a scout platoon during the Gulf War . These LAV-25s were returned to the Marine Corps after the conflict. The USMC ordered 758 vehicles of all variants. LAVs first saw combat during

2600-506: Was re-organized as the "Diesel Division of General Motors of Canada, Ltd." The plant was re-purposed to include manufacture of other diesel-powered General Motors vehicles such as buses. Following the Canada-United States Free Trade Agreement in 1989, all of EMD's locomotives were built at the London facility. In 2005 new owners of EMD renamed the Canadian subsidiary "Electro-Motive Canada". The plant

2652-570: Was renamed "Electro-Motive Diesel, Inc", thus retaining the EMD initials. EMD's Canadian subsidiary was renamed "Electro-Motive Canada". In 2010 EMD and its Canadian subsidiary were acquired by Caterpillar's subsidiary Progress Rail . The plant was closed in 2012, after a labor dispute and leasing of a new plant in Muncie , Indiana . In 2015 McLaughlin Brothers and J-AAR Excavating jointly acquire

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2704-487: Was used mainly as an armoured utility vehicle having a number of different sub-variants throughout its years of service. By starting with a basic LAV-25 , the Bison design process took only seven days. The Bison differs from the baseline LAV-25 by raising the height of the roof, removing the turret ring, placing a commander's cupola behind the driver, and incorporating a rail mount system in the cargo/passenger compartment to quickly change mission specific equipment. The driver

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