MCP: Model Checker for C++ (MCP) is an explicit-state software model checker being introduced by the Robust Software Engineering group at NASA Ames Research Center (Thompson and Brat, 2008). MCP was constructed specifically to allow programs written in C or C++ to be model-checked directly, devoid of requiring prior translation or model extraction. It builds upon the LLVM (low level virtual machine) compiler infrastructure (LLVM website), thereby avoiding the requirement to directly recognize the extremely complex C++ language at source-level. This approach allows MCP to support the entire C++ language, comprising templates. The C language is handled fully, not merely as an improper subset of C++. Experience from the JPF project has demonstrated the utility of program model checking. However, current flight software is mostly implemented in C, not Java, and in the future it seems increasingly likely that C++ will become the platform of choice. The MCP model checker was developed to fill the requirement for an explicit-state software model checker, in the style of JPF, that fully supports the C++ language. As a test example, it was applied to the unmodified C code of the prototype CEV Onboard Abort Executive Flight Rules Checker.