The Caterpillar D9 bulldozer is a commercial design, which is produced since 1955. It was designed and built in the United States. Since its introduction it has been constantly improved. The Caterpillar does not manufacture any special militarized version of this bulldozer. However this versatile earthmoving machine is employed for military applications. The US Army used Caterpillar D9 bulldozers during Vietnam War. These were used to clear forests. After the war these machines replaced with smaller Caterpillar D7G bulldozers.
Israeli Defense Forces acquired a number of these bulldozers. Previously the D9L and D9N versions were used by Israeli Engineering Corps. Operational experience of these machines in combat areas revealed, that protection from small arms fire and artillery shell splinters was required. Also Israeli Defense Forces were concerned that chemical attacks were possible. An add-on passive armor kit for the Caterpillar D9 bulldozers has been designed by Israeli Military Industries. Currently about 100 D9R armored bulldozers are in service with Israel. It seems that Israel also operates a newer D9T version. In 2003 US Army and Marine Corps acquired a total of 14 D9R armored bulldozers from Israeli army stocks for deployment in Iraq.
New armored cab was mounted on the vehicle’s frame. This add-on armor kit requires no modification to vehicle structure. Ergonomically positioned armored glass provides maximum ballistic protection with high visibility in all directions. Engine compartment is also armored. Large dozer blade acts as additional armor. It is claimed that overall weight of the machine increased by 6 000 kg, but it has no effect on the overall performance.
Armored cab provides protection against small arms fire and artillery shell splinters. Some sources claimed that IDF bulldozers withstood massive IED explosives and even deflected RPG rounds. Slat armor can be fitted for a higher level of protection against RPG rounds. The cab is sealed so vehicle can operate in areas contaminated with NBC agents. Optionally vehicle can be fitted with smoke grenade dischargers.
Armored Caterpillar D9 dozers can be used for a number of engineering tasks, including explosive ordnance disposal, clearing of booby-trapped areas, demolition of fortifications, route opening, recovery of stuck armored vehicles and construction of sand mounds and various obstacles, preparing defensive positions. The Israeli also use these armored bulldozers in the offensive in urban warfare. Previously these bulldozers were used under enemy fire to demolish houses. Also these machines were effective against dug in positions. The use of these machines in urban warfare proved to be effective and allowed to reduce Israeli casualties. These dozers can be also used for disaster relief operations. These machines proved to be suitable for low intensity conflicts, as well as full-scale combat.
This combat engineering vehicle is equipped with a detachable large blade and rear ripper attachment. All functions of the armored dozer, including its dozer blade and ripper can be operated remotely from the vehicle from a portable control panel.
The Caterpillar D9 dozer can easily tow main battle tanks and other combat vehicles that weight more than 70 tons.