The paper will provide a lifecycle cost-benefit analysis of the use of Prognostics and Health Management (PHM) systems and a conditioned-based maintenance (CBM) concept in future aircraft. The proposed method is based on a discrete event simulation for aircraft operation and maintenance and uses an optimization algorithm for the scheduling of CBM tasks. In the study, a 150-seat shortrange aircraft equipped with PHM and subject to a CBM program will be analyzed. The PHM-aircraft will be compared with an Airbus A320-type of aircraft and a traditional block check maintenance program. It will be possible to derive technical and economic requirements for prognostic systems and CBM concepts from the analysis results.