The purpose of this study is to clarify the changes and factors of a series of munitions factories that have been manufacturing and developing aircraft engines. Concretely, the transition of factory size and land use was clarified through the identification of the offices related to the daiko factory. This paper also examines the social conditions at that time and the policies of the military government and GHQ that influenced these factory transformations, and clarifies the spatial characteristics of the factory corresponding to most advanced production system in aircraft manufacturing.