There is a great interest in the planning community to apply all developments already achieved in the area to real applications. Such scenario makes the community focus on Knowledge Engineering (KE) applied in modeling of planning problems and domains. In this paper, we propose the use of UML for Planning Approach, denominated UML.P, during planning domain modeling process. We also discuss the exposure of UML.P to a real application, e.g., the sequencing car problems in an assembly line. This modeling experience, using a classical manufacturing problem, provides some insights and considerations that can contribute to a general KE process for planning.