The detail pipe fitting design method is presented here utilizing versatile CADS which is the man-machine system conversational with mini-computer and large table of analyzing and drafting. By this method pipe fitting detail plan can be designed. So far computerization in the outfitting arrangement design field has been fallen behind. The characteristics of this system are as follows : 1) Input Data can be generated by this system for the production design system, such as pipe piece drawing, pipe fabrication schedules, material lists etc., and all these data are connected to the large scale computer system in form of magnetic tape. 2) This system is connected to the automatic piping arrangement design system (PPAC-IHI Program) to design pipe outline arrangement plan by the use of large scale computer, and also generated the data for practising pipe design process from outline pipe arranging to detail pipe fitting and piece. drawings. 3) Several arbitrary ship's sections can be projected at on time on the wide table of CADS. 4) The ship's design data can be generated from this system by in-putting minimal data, using the master data files.