The Core Fighter was developed by the Hervic Company for the Earth Federation's Project V. It can be considered as the successor of the old FF-6 TIN Cod fighter jet. Since the data of Project V is essential to the Earth Federation's mobile suit development program, FF-X7 Core Fighters were designed to serve as cockpits for RX-75-4 Guntank, RX-77-2 Guncannon, and RX-78-2 Gundam (as well as RX-78-3 "G-3" Gundam) that are capable of being ejected and escape under their own power. Mobile suits with the Core Block System were composed of three modules: the upper torso and head, the Core Fighter which doubled as the cockpit and torso, and the hips and legs. The concept of the Core Block System was that if the mobile suits were damaged the pilots could escape by disconnecting the three main parts of the mobile suit and unfold the cockpit into its fighter form and then fly away to safety along with data collected in the Core Fighter's computer.
The Core Fighter uses a hybrid propulsion system of rocket thrusters and jets, it can operate effectively in the atmosphere as well as in space. While it wasn't designed for combat the Core Fighter is armed with 25mm Vulcan guns and missile launchers which allows it to fight against enemy fighter craft.
The Hervic Company eventually developed upgraded modules for the Core Fighter to increase its performance as support fighter (the G-Fighter in TV series and FF-X7-Bst Core Booster in movie edition). After the One Year War, the concepts of the Core Block System and the Core Fighter are continued to be used in various mobile suits.
The cockpit of the Core Fighter sports a drum design, which lowers the hit rate of the pilot and ups survivability. The cockpit also mounts a MFD (Multi-Functional Display).
The FF-X7 Core Fighter was developed as part of the Earth Federation's Project V as mobile suit cockpits and emergency escape craft to increase pilot survivability and to safeguard data acquired the Earth Federation's original nine combat ready mobile suit, of which only three participated in the war. Aside from their original purpose the Core Fighter could be used as a support craft to aid mobile suit in battle either in space or in the Earth's atmosphere. Though effective fighters against the Principality of Zeon's Dopp Fighters and Magella Attack Tanks they would have limited effectiveness during the war.
The Earth Federation ship White Base would field a number of these Core Fighters during the One Year War, however because the Core Block System proves to be too complicated and costly, thus not incorporated in mass production mobile suits, the production of the FF-X7 Core Fighter would be limited to a handful of units. Despite not being mass-produced itself the design would inspire new fighter craft such as the Jet Core Booster II. Still, with the advancement of mobile suit technology even these craft would be quickly phased out in favor of more powerful mobile suits.
After the war the FF-X7 Core Fighter would serve as the basis for future Core Fighters of more advanced Gundams. [Source: wikia]
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