Successful transition flights for Sikorsky ‘rotor-blown-wing’ UAS
March 10, 2025
Sikorsky’s prototype uncrewed aerial system (UAS) has made a series of successful transition flights between helicopter and fixed wing flight modes, reaching a top cruise speed of 86 kts in forward flight in January 2025.
Part of the Lockheed Martin company’s future family of systems (including winged VTOL drones and single main rotor aircraft), “our rotor blown wing platform is a prime example of how we are leveraging the breadth of our 102-year aviation heritage to develop new designs that meet the emerging missions of commercial and military operators,” explained Sikorsky vice president and general manager Rich Menton. He added that the combination of rotary- and fixed-wing flight characteristics “onto a flying wing reflects Sikorsky’s drive to innovate next-generation VTOL UAS aircraft that can fly faster and farther than traditional helicopters”.
Weighing 52kg, the battery-powered twin prop-rotor prototype was developed by rapid prototyping group Sikorsky Innovations. In just over a year, the aircraft has “progressed through preliminary design, simulation, tethered and untethered flight to gather aerodynamic, flight control and quality data,” explained Lockheed Martin.
The tail-sitting drone now has over 40 takeoffs and landings under its belt, in addition to having performed 30 transitions to forward flight; borne forward by its 10.3ft composite wings. Praising the “unique handling qualities necessary to transition repeatedly and predictably,” Sikorsky Innovations director Igor Cherepinsky added that “new control laws were required for this transition manoeuvre to work seamlessly and efficiently”.
Data gathered from real-world flight tests (alongside 1:1 scale wind tunnel modelling) “indicates we can operate from pitching ships decks and unprepared ground when scaled to much larger sizes,” he concluded.
Lockheed Martin indicated that future applications of UAS rotor-blown-wing aircraft include SAR, firefighting monitoring, humanitarian response and pipeline surveillance missions, while larger-scale variants could enable long-range intelligence, surveillance and reconnaissance, and piloted crewed-uncrewed missions. Also in development, a power system test bed of Sikorsky’s tilt-wing VTOL HEX – a 1.2 megawatt hybrid-electric demonstrator – is expected to demonstrate hover capability in 2027.
