A Mandatory KPP that is intended to ensure that materiel aspects of training capabilities, when applicable, are addressed as part of the development of the capability solution outlined in the Capability Development Document (CDD) or updated CDD. Nonmateriel aspects of training are to be captured as part of the Doctrine, Organization, Training, materiel, Leadership and Education, Personnel, Facilities-Policy (DOTmLPF-P) section of the CDD or CPD. Situations requiring a Training KPP may include long mission durations of submarine operations, which may necessitate that certain training and simulation capabilities be integrated into the weapon system, or during the system's mission training. For example, a flight simulator to substitute for some aspects of training when training events would be too dangerous to perform or it would be more cost effective to use a simulator.