M1025 HUMVEE Somalia

In 1979, the U.S. Army drafted final specifications for a High Mobility Multipurpose Wheeled Vehicle (HMMWV), which was to replace all the tactical vehicles in the 1/4 to 1 1/4-ton range. The specification called for excellent on and off-road performance, the ability to carry a large payload, and improved survivability against indirect fire. AM General was awarded an initial contract in 1983 for 2,334 vehicles, the first batch of a five-year contract that would see 55,000 vehicles delivered to the U.S. military, including 39,000 vehicles for the Army; 72,000 vehicles had been delivered to U.S. and foreign customers by the Persian Gulf War of 1991, and 100,000 were delivered by the Humvee's 10th anniversary in 1995.
The Humvee seats 4 with an available fully enclosed metal cabin with a vertical windshield. The body is constructed from lightweight and rust-resistant aluminum, instead of conventional steel. It has all-wheel drive with an independent suspension and helical gear-reduction hubs similar to portal axles which attach towards the top rather than center of each wheel to allow the drivetrain shafts to be raised for a full 16 in (410 mm) of ground clearance. The body is mounted on a narrow steel frame with boxed rails and five cross members for rigidity. The rails act as sliders to protect the drivetrain which is nestled between and above the rails. Raising the drivetrain into the cabin area and lowering the seats into the frame creates a massive chest-high transmission hump which separates passengers on each side and lowers the overall center of gravity compared to most trucks where the body and passengers are above the frame. The vehicle also has disc brakes on all 4 wheels, and 4-wheel Portal axle double-wishbone suspension. The brake discs are not mounted at the wheels as on conventional automobiles, but are inboard, attached to the outside of each differential. The front and rear differentials are Torsen type, and the center differential is a regular, lockable type. Torque-biasing differentials allows forward movement as long as at least one wheel has traction. It runs on specialized 37 × 12.5 radial tires with low-profile runflat devices. Newer HMMWV versions can be equipped with an optional central tire inflation system (CTIS) kit in the field. While it is optimized for off-road mobility, it can drive at highway speeds of 55 mph (89 km/h) at maximum weight with a top speed of 70 mph (110 km/h).
Vehicles and crews suffered considerable damage and losses during the Battle of Mogadishu in 1993 due to the nature of the urban engagement. However, the chassis survivability allowed the majority of those crews to return to safety, though the HMMWV was never designed to offer protection against intense small arms fire, much less machine guns and rocket-propelled grenades. With the rise of asymmetric warfare and low intensity conflicts, the HMMWV was pressed into service in urban combat roles for which it was not originally intended.