The points of this paper are as follows ; 1) Adopting the tact system to the hull erection stage. In this case, the tact system means the production control based on the detailed program. 2) To serve the above-mentioned purpose, the fundamental program and detailed one are to be formed. The former decides and makes sure the process and schedule of works, such as fitting, welding and so on. The latter, the best arrangements of facilities to carry out the fundamental programs on crane, working and welding machine.
