Logistics ECP. The DON has been authorized to invest Navy Working Capital Funds (NWCF) into the development of less costly and/or more reliable spare and repair parts. The vehicle to implement these investments is the logistics engineering change proposal (LECP). In essence, an LECP is a reliability or maintainability related Engineering Change Proposal (ECP) designed to reduce or eliminate support costs while maintaining or improving safety and performance. These proposals must embody a low risk, rapid return on investment.