 |
|
| ||||||||||||||||||||||||||
|
|
| ||||||||||||||||||||||||||
|
|
|
|
|
| ||||||||
| Caterpillar D9 - General Characteristics | |
| Engineering vehicle type: | Heavy bulldozer |
| Propulsion: | Caterpillar tracks |
| Engine model: | 3408 HEUI (D9R) |
| Gross power: | 354 kW (474 hp) D9R |
| Flywheel power: | 306 kW (410 hp) D9R 280 kW (375 hp) D9N 343 kW (460 hp) D9L |
| Operation Weight: | 48784 kg (107548 lb) | Length: | 8.1 m |
| Width: | 4 m (blade) |
| Height: | 4 m |
| Speed: | 11.9 km/h (foward) 14.7 km/h (reverse) |
| Blade capacity: | 13.5 m³ (17.7 yd³) 9 SU blade 16.4 m3(21.4 yd³) 9 U blade |
The Caterpillar D9 is a large track-type tractor (commonly referred to as a bulldozer) with caterpillar tracks designed and manufactured by Caterpillar Inc.. The D9, with 354 kW (474 hp) of gross power and an operating weight of 49 tons, is in the upper end, but not the heaviest, of Caterpillar's track-type tractors, which range in size from the D3 57 kW (77 hp), 8 tons, to the D11 698 kW (935 hp), 104 tons. The size, durability, reliability, and low operating costs has made the D9 one of the most popular large track-type tractors in the world, with the Komatsu D275A as one of its most direct competitors.
The D9's primary working tools are the blade, affixed to the front and controlled by 6 hydraulic arms, and the optional ripper, which can be attached to the back. The blade is mainly intended for earthmoving and bulk material handling: pushing up sand, dirt and rubble. It also can be used to push other heavy equipment such as earthmoving scraper pans, and in military applications, main battle tanks. Like many other bulldozers, the D9 can be fitted with different blades (such as size-9 SU blade and Universal blade) or other devices such as mineplows or combine harvester. The rear ripper is intended for use in loosening rocky ground and ripping out larger stones. It can also break frozen ground and excavate small ditches.
The D9 has undergone several generations of engineering enhancements. The D9L was the first variation of the D9 to employ "high drive" design. The current version is the D9R but the older models such as the D9N and D9L are still common. The L, N and R models of the D9 are visually very similar, differing primarily in the design of their internal systems.
The size and weight of the larger track-type tractors dictate that they are used primarily for major projects. The D9 is most commonly found in use in construction, forestry, mining, waste, and quarry operations.
On the 4th of June, 2004 a Granby, Colorado, USA resident by the name of Marvin Heemeyer ran amok driving a modified D9 and destroyed several houses and community buildings in the small farming village of Granby. He crashed the buildings of his adversaries in a zoning dispute involving his muffler shop and a new concrete mixing plant. Heemeyer fitted makeshift concrete armor to the vehicle, turning it into a tank-like mobile fortress. The cabin, engine and tracks were protected by reinforced concrete armor that was, in places, over one foot thick. The driver's vision of where he was going was provided by video cameras outside the driver's compartment feeding three CRTs inside. Heemeyer also provided food, water, and air conditioning for himself inside the fortified driver's cabin. The bulldozer was armed with several rifles and a .50 caliber (12.7 mm) gun. The D9 itself was an old model that was no longer in production.
During the one-and-a-half hour rampage, law enforcement officers fired hundreds of bullets at the makeshift tank and set off explosive charges against it, but could not stop the D9's rampage. Finally the fortified D9 came to rest, trapped in the rubble of a collapsed building. A failed radiator brought the vehicle to a halt. Heemeyer apparently took his own life in his cockpit, while SWAT teams were using explosives and blowtorch welders to gain access to the driver's compartment.
Although nobody else was killed in the incident, property damage was very extensive. According to many reports, Heemeyer went out of his way to avoid killing innocents, and apparently the purpose of his rampage was solely to cause extensive property damage to his 'enemies.'
See: killdozer.
Caterpillar Inc. does not manufacture a military version of the D9 per se, but the attributes that make the D9 popular for major construction projects make it desirable for military applications as well, and it has been particularly effective for the Israeli Defense Force (IDF).
Armored bulldozers are a standard tool of Combat engineering battalions, and the IDF has gained some notoriety for their use of armored tractors for urban warfare in the Al-Aqsa Intifada. Although the Israeli Engineering Corps had used D9 bulldozers since the 1960's (including in the Six Day War and Yom Kippur War), the D9 first rose to public attention in Operation Defensive Shield, in later demolition of structures and shrubbery, and in the consequential death of Rachel Corrie. In Israel, the D9 has gained a high positive reputation for keeping IDF casualties low and for saving soldiers' lives.
The armored D9, as developed and modified by the IDF, provides armor protection to the mechanical systems and to the operator cabin. The operator is protected by bulletproof glass to protect against bombs, machinegun and sniper fire. The fitted armor package adds roughly 15 additional tons to the production-line weight of the D9. As for many customized packages, individually modified D9s may be found with disparate features, such as crew-operated machine guns, smoke projectors, or grenade launchers.
The Israeli Engineering Corps is using the D9 for a wide variety of engineering tasks: digging moats and building fortifications, as well as clearing terrain obstacles and opening routes to Armored fighting vehicles. One of the D9's primary roles is to clear landmine fields and booby-trapped areas. The heavy armor installed by the IDF allows the D9s to work under heavy fire in dangerous battle-zones. The Israeli armor kit has proven to be effective, as no D9 operator was killed during the 4-year long al-Aqsa Intifada.
The Israeli armored D9, a.k.a Duby (lit. teddy bear) has also been used in standoff situations with armed opponents barricaded in buildings, usually rigged with explosives and booby-traps, when no hostages are present. In order not to risk Israeli soldiers, the D9 shakes the house until the barricaded gunmen surrender. After the building is evacuated, the D9 razes the structure in order to detonate and bury any explosives that remain inside. This method was also employed (with great success) in Jenin during Operation Defensive Shield after 13 Israeli soldiers were killed in an ambush. In Hebron, the IDF used the armored D9 to stop the local Hamas leader, Bassal Qawasameh, whose forces shot at the D9, but he was killed when the D9 collapsed the house where he was hiding. ().
Armored D9 bulldozers are routinely employed in the Gaza strip as well. Their main tasks there are to detonate large explosive charges (such as improvised anti-tank landmines,booby traps and IEDs) and clear safe paths for IDF armored fighting vehicles and troops. The D9s also demolish houses and clear shrubbery that the opposition can use as shooting cover. The D9s are an essential tool in the IDF campaign against smuggling tunnels in Rafah, which are used by militants to smuggle weapons, persons and contraband. Armored D9 bulldozers have demolished many structures in Rafah during battles with militants and operations to uncover smuggling tunnels. The destruction of hundreds of structures in Rafah is a highly controversial issue: the Israeli Defense Forces claims that the destruction of buildings and tunnels is a security necessity and that most houses destroyed were used for terrorist activity. Palestinians claim the destruction has left thousands of people homeless and is done systematically in order to create a cleared "buffer zone" between Rafah and Philadelphi Route.
Both military armored D9s and civilian non-armored D9s are being used by Israel's Ministry of Defense in the building of the Israeli West Bank barrier. The main D9 contributions to the project are earthmoving and soil-leveling, clearing a path for the security fence, and digging trenches in front of the security fence.
The United States Army has purchased several D9 armor kits from the IDF and used them to produce similarly fortified D9s. These have been used to clear destroyed vehicles from roads, dig moats, erect earthen-barriers, and construct field fortifications. D9s have also been used to raze houses which hosted snipers who shot at American forces (similar to the Israeli usage). There were some reports about the use of large bulldozers against Iraqi trenches during the first Gulf War.
The US army used D9 bulldozers to clear wood in Vietnam war but after the war it replaced them with smaller and cheaper Caterpillar D7 bulldozers. D7 dozers are still very common in US combat engineering battlions, but there is a resurgent high demand to replace the lighter D7s with the newer and more heavily armored D9s.
|
||||
| View Live Article | This article is from Wikipedia. All text is available under the terms of the GNU Free Documentation License | |
||
