By the time of the One Year War, the Principality of Zeon's lead Newtype researcher, Dr. Flanagan, had been conducting his research for more than ten years. In contrast, the Earth Federation Forces only began their Newtype research in August, U.C. 0079. This was because the EFF did not see the military value of Newtypes due to the small number of examples and low replicability.
However, concepts similar to Newtype-use unit were still included as part of the RX Project. Based on existing research to improve mobile suit responsiveness, as well as reports from the Newtype pilot Amuro Ray and operating data from the RX-78-2 Gundam, the EFF began the development of a Newtype-use mobile suit with the goal of improved durability and responsiveness. For this purpose, the fourth RX-78 series unit was redesigned as a custom unit for Amuro Ray and received the new model number of RX-78NT-1.