 The design of the RP-77D made extensive use of glass-polyester plastic materials. The drone was launched using a rocket-assisted take-off system consisting of four Loki rockets, and was fitted with a radio control apparatus that, with the assistance of radar tracking, allowed the drone to be operated at a considerable distance from its launching point. In addition to equipment typically carried by target drones, the RP-77D could be equipped with reconnaissance or meteorological sensors, or with air sampling equipment. The RP-77D utilised the RPTA tracking system, developed by Radioplane, using audio frequency tones for control. Tip tanks allowed for carriage of additional fuel to extend the aircraft's range, and recovery at the end of the flight was by parachute.
