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, namely the M151 quarter -ton jeep and M561 Gama Goat, as one "jack-of-all-trades" light tactical vehicle to perform the role of several existing trucks. The specification called for excellent on and off-road performance, the ability to carry a large payload, and improved survivability against indirect fire. Compared to the jeep, it was larger and had a much wider track, with a 16 in (410 mm) ground clearance, double that of most sport-utility vehicles. The new truck was to climb a 60 percent incline and traverse a 40 percent slope. The air intake was to be mounted flush on top of the right fender (or to be raised on a stovepipe to roof level to ford 5 ft (1.5 m) of water and electronics waterproofed to drive through 2.5 ft (0.76 m) of water were specified. The radiator was to be mounted high, sloping over the engine on a forward-hinged hood.
Out of 61 companies that showed interest, only three submitted prototypes. In July 1979, AM General, a subsidiary of American Motors Corporation began preliminary design work. Less than a year later, the first prototype was in testing. Chrysler Defense and Teledyne Continental also produced competing designs. In June 1981, the Army awarded AM General a contract for development of several more prototype vehicles to be delivered to the government for another series of tests. The original M998 A0 series had a curb weight of 5,200 lb (2,400 kg), a payload of 2,500 lb (1,100 kg), a 6.2 L (380 cu in) V-8 diesel engine, and a three-speed automatic transmission.
The three companies were chosen to design and build eleven HMMWV prototypes, which covered over 600,000 miles in trials which included off-road courses in desert and arctic conditions. 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. Ft. Lewis, Washington and the 2nd Battalion 1st Infantry, 9th Infantry Division was the testing unit to employ HMMWV in the new concept of a motorized division. Yakima Training Center in Yakima, Washington was the main testing grounds for HMMWVs from 1985 through December 1991, when the motorized concept was abandoned and the division inactivated.
Usage in Combat
HMMWVs first saw combat in Operation Just Cause, the U.S. invasion of Panama in 1989.
The HMMWV was designed primarily for personnel and light cargo transport behind front lines, not as a front line fighting vehicle. Like the previous jeep, the basic HMMWV has no armor or protection against chemical, biological, radiological or nuclear threats. Nevertheless, losses were relatively low in conventional operations, such as the Gukf War. 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.
After Operation Restore Hope in Somalia, the military recognized a need for a more protected HMMWV and AM General developed the M1114, an armored HMMWV to withstand small arms fire. The M1114 has been in production since 1996, seeing limited use in the Balkans before deployment to the Middle East. This design is superior to the M998 with a larger, more powerful turbocharged engine, air conditioning, and a strengthened suspension system. More importantly, it boasts a fully armored passenger area protected by hardened steel and bullet resistant glass. With the increase in direct attacks and guerrilla warfare in Iraq, AM General diverted the majority of its manufacturing power to producing these vehicles.
Humvees were sent into Afghanistan following the 9/11 terrorist attacks, where they proved invaluable during initial operations. In the early years before IEDs became prevalent, the vehicle was liked by troops for its ability to access rough, mountainous terrain. Some soldiers would remove features from Humvees, including what little armor it had and sometimes even entire doors, to make them lighter and more maneuverable for off-road conditions and to increase visibility. With the onset of the Iraq War, Humvees proved very vulnerable to IEDs; in the first four months of 2006, 67 U.S. troops died in Humvees. To increase protection, the U.S. military hastily added-on armor kits to the vehicles. Although this somewhat improved survivability, bolting on armor made the Humvee an "ungainly beast," increasing weight and putting strain on the chassis, which led to unreliability. Armored doors that weighed hundreds of pounds were difficult for troops to open and the newly armored turret made Humvees top heavy and increased the danger of rollovers. The U.S. Marine Corps decided to start replacing Humvees in combat with MRAPs in 2007, and the U.S. Army stated that the vehicle was "no longer feasible for combat" in 2012.
The HMMWV has become the vehicular backbone of U.S. forces around the world. Over 10,000 HMMWVs were employed by coalition forces during the Iraq War. The Humvee has been described as "the right capability for its era" to provide payload mobility in protected areas, but that conflicts exposing it to full-spectrum threat environments that it was never designed to operate or be survivable in led to adding protection at the cost of mobility and payload.