PT. Dirgantara Indonesia had a delay project for five aircrafts of n212-400 ordered by the Phillipines and Vietnam. This is a qualitative research using a case study approach in the identification of the causative factor of project delay, with the purpose of study using descriptive research and the process data validity and reliability using triangulation method. The data analysis in this research was the productivity of project, potential failure mode of the project using FMEA (Failure Mode and Effect Analysis) and fishbone diagram to determine the cause and effect of the project delay. The result of the productivity during N212-400 project was 40%, and in aerospace industry, this is below its average of 70% - 80%. Using fishbone and FMEA, the cause of delay and the potential failure of delay project N212-400 was identified and the main factor of project delay based on fishbone and FMEA was machine and material process. Both of the key factors had a high score of RPN (Risk Priority Number) at 810 and should be given priority for improvement.