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Armored Truck
Armored TruckAn armored truck is a vehicle designed to securely transport currency and other valuables. BackgroundBefore the advent of armored vehicles, securely moving currency and valuables was achieved either by deceit or by force of arms. In the case of deceit, a courier in plain clothes would carry valuables disguised as a normal package or small piece of luggage. The courier traveled as a passenger on public means of transport, and although he was armed, his primary protection lay in appearing to be an average traveler. The main restriction of this method was size. In order to protect large shipments of valuables, man has long relied on a force of arms. Early caravans surrounded themselves with armed troops. Spanish galleons bristling with cannons carried treasure from the New World. In more modern times, stagecoaches carried locked but far from impregnable strong boxes of iron and wood, while a guard "rode shot-gun" to ward off thieves. Railroad mail cars were outfitted with safes and were guarded by heavily armed government troops. The failure of this method was always twofold. First, although cargo was relatively safe while in its large, protected vessel, eventually it needed to be placed in smaller, more vulnerable vehicles to be carried to its final destination. The second problem was that no matter how many soldiers, swords, rifles, or cannons guarded a travelling precious cargo, a larger force of thieves with more swords, rifles, or cannons could be rallied to steal the cargo. As weapons became dead-lier and more compact, this became more of a problem. The first attempts at commercial armored trucks were inspired by the combat success of military armored cars in World War I. After the war, a marked increase in violent robberies of payroll clerks and messengers carrying deposits brought about the need for safer ways to transport cash. In 1920, a Chicago area delivery company called Brink's started converting school buses into security vehicles by attaching steel plates to the lower body panels and barring the windows. Each bus was followed by a Model-T automobile filled with armed guards. The first true commercial armored car was built that same year in Minneapolis, Minnesota, for a St. Paul police chief turned private detective Mike Sweeney. Sweeney designed the car and put it into service for his Sweeney Detective Bureau. Early armored cars only wore steel plating on their body panels; they retained the wooden floors of the truck chassises on which they were built. This ended in 1927 when thieves buried explosives in the road and blew up a Brink's truck carrying $100,000 in payroll money. In the 1930s and 40s, manufacturers experimented with aluminum, which has a distinct weight advantage over steel. The metal was found to fatigue and crack after a short time and was discontinued. The 1970s worldwide fuel shortage spurred manufacturers to try lightweight plastic armor and smaller, more fuel-efficient chassises, but the results were similar to those with aluminum and the traditional steel regained its dominance in the industry. Raw MaterialsThe material that makes up most of an armored car is also what makes it armored. The walls, floor, ceiling, and doors of an armored car are all made from steel. In recent years, both galvanized and stainless steel have been used to combat body rust and corrosion. The steel is hardened to increase its bullet resistance, either by heat treatment or by adding high levels of chromium (a very hard metal) and nickel (a very dense metal) during the forging process. In some applications, a ballistic fiberglass cloth known as woven roving is used to line the interior of the body. The windows of the truck are either made up of several layers of automotive glass or of layers of glass mixed with layers of bullet-resistant optical plastic. DesignFour equally important goals must be considered in the making of an armored truck, several of which work against each other. The first consideration is ballistic resistance. Manufacturers use hardened steel in thick-nesses varying from 0.125 in (0.317 cm) to greater than 0.25 in (0.635 cm), depending on the level of resistance required to build most of the body of an armored truck. Windows are made bullet resistant by using laminated glass in thicknesses between 1.50 in (3.81 cm) and 3 in (7.62 cm). Utilizing a mixture of glass and bullet-resistant optical plastic allows a much thinner and lighter window. Windshields are placed at a 45-degree angle to aid in deflection and to lower wind resistance. Tires are armored with a u-shaped hard plastic liner. If a tire deflates, it can run for several miles on the structure of this shell. Steel ram bumpers and front grill guards allow a driver to push through another vehicle that may be used as a roadblock. Increasing a truck's level of ballistic resistance means increasing the thickness of the steel and glass used and this works against the second design consideration—weight. Gross Vehicle Weight (GVW) measures the maximum a motor vehicle can safely weigh, including its cargo and passengers. The average GVW for a "route truck," which makes everyday pickups and deliveries for banks and merchants, is 25,000 lb (11,350 kg). The average finished route truck weighs 12,000 lb (5,448 kg). This leaves 13,000 lb (5,902 kg) for cargo and guards. Reducing the finished weight of a truck allows for greater cargo weight. Decreasing the amount of armoring is not an attractive option, so trucks that need to haul heavier cargo, such as coins, must be built on larger, heavier chassises. A tandem-axle truck designed to haul large pallets of coin can have a GVW upwards of 55,000 lb (24,970 kg). The third design consideration is security. Clearly, bullet resistance is of little use if the truck's operators and cargo are not securely separated from the outside world. With this in mind, security measures are aimed at installing and maintaining barriers. Most armored cars operate with two armed guards—a driver, who never leaves the vehicle, and a second guard known as a hopper, who rides in the cargo hold and carries valuables to and from the truck. The driver's compartment is separated from the cargo area by a steel bulkhead. The doors through which the hopper travels are fitted with slam locks, which automatically lock when the door swings shut. Once these doors are locked, the driver must reopen them electronically from the inside. Inside the cargo area, the hopper may place valuables inside a locked box, or he may use a drop safe, which has a one way chute and can only be opened once the truck has returned to its home facility. The gun ports installed in each door employ a spring-loaded plate that must be slid open from the inside to prevent assailants from using them to fire into the vehicle. The security requirements necessitate additional steps to accomplish the final design goal—crew comfort. An armored car is basically a large, sealed metal box and is thereby very hot inside. The windows do not roll down for obvious reasons, so most trucks have four roof vents with a baffle to obstruct any direct lines of fire into the truck. Trucks are also fitted with dual air-conditioning and heating units, so the hopper and driver can independently adjust temperatures. The walls, ceiling, and floor of the cargo area are lined with light-weight foam-board insulation to further regulate inside temperatures. 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Cite this article
"Armored Truck." How Products Are Made. 1999. Encyclopedia.com. 9 Feb. 2012 <http://www.encyclopedia.com>. "Armored Truck." How Products Are Made. 1999. Encyclopedia.com. (February 9, 2012). http://www.encyclopedia.com/doc/1G2-2896800013.html "Armored Truck." How Products Are Made. 1999. Retrieved February 09, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1G2-2896800013.html |
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armored vehicle
armored vehicle any land vehicle made with heavy or light external armor that protects its crew and structural integrity.
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Cite this article
"armored vehicle." The Oxford Essential Dictionary of the U.S. Military. 2001. Encyclopedia.com. 9 Feb. 2012 <http://www.encyclopedia.com>. "armored vehicle." The Oxford Essential Dictionary of the U.S. Military. 2001. Encyclopedia.com. (February 9, 2012). http://www.encyclopedia.com/doc/1O63-armoredvehicle.html "armored vehicle." The Oxford Essential Dictionary of the U.S. Military. 2001. Retrieved February 09, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O63-armoredvehicle.html |
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