Optionally piloted vehicle
An optionally piloted vehicle (OPV) is a hybrid between a conventional aircraft and an unmanned aerial vehicle (UAV).
Able to fly with or without a human crew on board the aircraft, OPVs are a low-cost alternative to UAVs in research, experimentation, and concept exploration, but may also become used in mainstream operations as familiarity with them increases. Unimpeded by a human's physiological limitations, an OPV is able to operate under more adverse conditions and/or for greater endurance times. Retaining on-board controls, the OPV can operate as a conventional aircraft during missions for which direct human control is preferred or desired as an immediate option.