Technology & Combat Characteristics
A state-of-the-art machine adopted by the Earth Federation Forces in U.C. 0089 as its main force mobile suit, the RGM-89 Jegan comes from the lineage of the RGM-79 GM as inferred by its "RGM" model number. However, it was not developed by the Earth Federation Forces' own engineers like most previous RGM series mobile suit. It also has improved productivity due to the use of Titanium Alloy Ceramic Composite armor, as well as high operability, and excellent versatility. All these allows it to become the "next-generation standard MS", and it operated as the main force MS for a long period of time. Several variations of the MS were also developed.
The Jegan highly exemplified the original concept of MS being "mobile infantry for melee combat", and is designed for close combat in and around space colonies. It can also operate under gravity without any modifications. With a backpack containing a single main thruster, two small thrusters at the bottom, and two articulated vernier arms at the top, the Jegan's thrust and acceleration performance could match high-mobility-type machines from the Gryps War-era. Its backpack also featured exchangeable propellant tanks. Also notable are the verniers for attitude controls on the front shoulder armor, enlarged centre shoulder armor sections to fit the side thrusters, and a calf-mounted thruster on each leg. The use of lightened armor grants the machine high maneuverability, its front skirt armor is removed to maintain the legs' range of articulation, while its head has a long-range sensor installed in the forehead in addition to the fixed main sensors. The Jegan is armed with mainly short-range weaponry, including a beam saber, a short-range type beam rifle, three hand grenades, a vulcan pod system, and a shield with twin missile launchers.
History
The Jegan was officially adopted by the Earth Federation Forces in U.C.0089. The Second Neo Zeon War in U.C. 0093 was the first major engagement in which the Jegan was deployed. There were less than 100 Jegans at that time, which were mainly used by the Londo Bell taskforce and the Luna II garrison, as the machine was still in its early stages of deployment. Despite this, Londo Bell's Jegans played a pivotal role in the conflict. After the conflict, the Jegan became the mainstay mobile suit of the Federation Forces.
As with most mass-produced mobile suits, the Jegan was used as a basis for specialized units such as the RGM-89S Prototype Stark Jegan, which was capable of mounting large missiles -even nuclear warheads- and the special operations suit RGM-96X Jesta. Over its long period of service, the Jegan kept itself relevant through frequent upgrades. For example at the time of Crossbone Vanguard uprising in U.C. 0123, the Jegan, in the form of the RGM-89J Jegan Normal Type, was still more widely deployed than its more modern counterpart – the RGM-109 Heavygun.