In the Gundam development plan launched in UC0081, the goal was to recategorize the mobile suits by assuming every battle situation and develop the best and strongest suit. Reconstructing the strengths of the convertible mobile suit proven in the RX-78, the design proposal aimed at high efficiency from the basic design to mass production is an attack aircraft for combat combat that incorporates thorough versatility. The first draft of the , the second draft of the heavily armored assault attack type focused on nuclear attack, the third draft of the large mobile armor for base defense and base capture and the control center mobile suit, and the assault type specialized for space combat. As a result of the development of the actual machine while searching for the sub-plan in parallel, all of these aircraft were completed in about two years from the planning. The actual design and manufacture of the airframe was carried out by Anaheim Electronics, which would continue to expand its business after that (the Earth Federation Forces did the planning and budgeting, but in reality they outsourced all of this. Therefore, various detailed records were never completely under the control of the Earth Federation government and the Federation Forces). Although these aircraft are completely new designs, they are given the model number of the RX-78GP series and approved as including the development code as part of showing the majesty of the Earth Federation Forces (However, it broke out without delay. In the Delaz conflict, these aircraft were involved in an unintended manner by the Federation Forces, and all GP01 to 03 disappeared in battle. In order to conceal it, all records of the Gundam development plan were deleted from the defense white paper of the same year). Also known as the Anaheim Gundam, these aircraft were actually produced with a huge military development budget, and in terms of the capabilities and perfection of the so-called mobile suits alone, the second-generation mass-produced mobile suits that will be maintained after UC0087. It was much higher than In particular, the design of GP01, which is the basis of each plan proposal, is excellent in mounting and exchangeability of each part of the aircraft utilizing the core block system, and specification changes such as combat aircraft under gravity and space battle compatible aircraft It can be said that it laid the foundation for the later movable frame design. The RX-78GP03S Steimen, which focuses on the control center control function by connecting with the Orchis, which is a large high-mobility armament Form, is a Gundam whose operation is specified, so to speak, a single-machine assault type specialized for space battles. The RX-78GP04G Gerbera was designed differently as an attack aircraft. While previous mobile suits were short-legged carrier-based aircraft that required a mother ship, this model was designed with the aim of operating the aircraft with a relatively long cruising range in mind. Here too, the composite outer shell concept cultivated in the core block system is utilized, and the Gundam body, which is specialized for high-mobility combat by itself, is combined with an external propellant tank unit in a backpack. Equipped with a separate booster (there was also a plan to convert it into a partially armed container), it was possible to extend combat cruising range and perform high-speed mobile attacks. The prototype was completed at about the same time as the GP03S Steimen, and the vernier units (especially the shoulders) of each part of the fuselage are organized in a form that follows the layout of the legs, so compared to the modified GP01Fb and GP03S Finished in a silhouette without discomfort. Since the mainframe and exterior parts were all subject to overhaul inspections for each trial, the completed aircraft was in the midst of the outbreak of the Delaz conflict, and the Anaheim headquarters was about to undergo the approval procedures of the Federal Forces Development Headquarters, which included high-ranking government officials. was reserved. Upon receiving news of Lieutenant General John Cowen's dismissal, the head office of the Headquarters sensed that this plan was cancelled, and decided to suspend the scheduled delivery to the Federation Forces Headquarters by dispersing and transferring this aircraft in a dismantled state. In addition, when the military moves to settle the situation, all the development data is collected from the main computer along with the backup. It is said that this was a quick decision by CEO Melanie Hugh Carvine.