Tiltduct UAVs are equipped with ducted propellers, generating up to 60% more thrust efficiency than conventional open-rotor UAVs. By adopting helicopter-style lift and ducted rotor wings, the system not only enhances thrust and protects the rotors from ground obstacles but also allows ground-based systems to assign, monitor, and control missions during operation.
The TD-40 tiltduct UAV was developed from 2012 to 2017 as part of the Ministry of Trade, Industry, and Energy’s core technology project for robotics convergence, specifically under the theme “Development of Multipurpose VTOL Flight Robot System Capable of Flying Over One Hour.” The performance requirements included a top speed of over 150 km/h, a minimum endurance of 1.5 hours, and precision control enabling automatic takeoff and landing via a mobile docking station. The system includes the UAV, ground control station, and communication equipment. The ground control setup consists of a laptop running proprietary GCS software, a handheld controller, and a knob-type input device. The UAV itself is equipped with a flight control computer that integrates sensors and communication modules. Each tiltduct features a ring-shaped duct structure that houses a main propeller with collective pitch control and vanes designed for precise attitude management. A 15-horsepower rotary engine powers the system, with a rear-facing pusher propeller mounted between the horizontal and vertical stabilizers.
The control method for the tiltduct UAV varies depending on the flight mode. In rotary-wing mode, the UAV maintains attitude using the collective pitch of the main and rear propellers. As the tilt angle transitions toward fixed-wing mode, control shifts to the duct vanes and control surfaces of the horizontal tail. Tethered test flights were conducted to evaluate the characteristics of rotary-wing flight and duct performance, which led to enhanced control logic and improved maneuverability.
In 2017, KARI conducted the maiden flight of the tiltduct UAV at the Goheung Aerospace Center, achieving a flight speed of 153 km/h. The flight tests proceeded in phases—starting with hover flights, followed by rotary-wing mode, a station-keeping mode manually controlled by an internal operator, and concluding with fully autonomous transition flights. The UAV demonstrated endurance exceeding 1.5 hours and cruising speeds above 150 km/h. The external docking station enables takeoff and landing even on roadways during emergencies, increasing operational flexibility. The UAV is also suitable for deployment in areas without runways or in confined spaces, supporting missions such as fire and security surveillance, real-time monitoring of flora and fauna, vehicle tracking, and remote diagnostics of large structures.