During a pre-Verticon media event held at Sikorsky’s facility in Stratford, Connecticut, Vertical was briefed on the latest progress of the company’s foray into uncrewed aerial systems (UAS), its “rotor blown wing.”
That moniker is derived from the design of the UAS, which incorporates the vertical lift capabilities of a helicopter and the forward speed of an airplane into a novel tail-sitting configuration, wherein the thrust is forced down the chord line of the wing.
Once vertical lift is achieved, the aircraft transitions into forward flight.
“Combining helicopter and airplane 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,” said Rich Benton, Sikorsky vice president and general manager.
“Our rotor blown wing platform is a prime example 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.”
In January of this year, Sikorsky successfully completed more than 40 take-offs and landings.
During this testing, the aircraft also performed 30 transitions from vertical to horizontal flight, which Sikorsky said is, “the most complex maneuver demanded of the design.”
Top cruise speed of 86 kts was achieved. The test aircraft has a 10.3-foot (3.14-meter) wingspan, weighs 115 pounds (52 kilograms), and is outfitted with two battery-powered motors. All rotor blown wings will be operated via Sikorsky’s own MATRIX flight autonomy system.
“Our rotor blown wing has demonstrated the control power and unique handling qualities necessary to transition repeatedly and predictably from a hover to high-speed wing-borne cruise flight, and back again,” said Igor Cherepinsky, Sikorsky innovations director.
“New control laws were required for this transition maneuver to work seamlessly and efficiently. The data indicates we can operate from pitching ships decks and unprepared ground when scaled to much larger sizes.”
Sikorsky believes applications of future UAS rotor blown wing aircraft include search-and-rescue, firefighting monitoring, humanitarian response, and pipeline surveilling. Large variants will enable long-range intelligence, surveillance and reconnaissance, and piloted drone teaming (crewed/uncrewed teaming) missions.
The success of this test program is instrumental in the future plans of the next generation of aircraft that Sikorsky is working on.
The “Hybrid-Electric Family of Systems” includes four models of ascending size. The UAS rotor blown wing demonstrator is the first step.
A sibling of the UAS is the e-76 Concept that resembles a current S-76 but is designed to utilize various levels of electrification.
“We’re not necessarily planning to convert an S-76 into electric power, but we did use that platform as a study to see what would happen if we were to take an aircraft of that size and add hybridization,” explains Cherepinsky.
Stepping up from the e-76 is a vehicle that Sikorsky is currently in the process of building, the hybrid-electric demonstrator, HEX.
This aircraft will be a 9,000-pound (4,082-kilogram) UAS incorporating a single turbine powered by a 1.2-megawatt electric motor that is being developed in partnership with General Electric.
It will integrate the knowledge learned from the rotor blown wing and incorporate that design into a passenger-carrying configuration. The HEX will be a tilt-wing configuration with the rotor blown wing mounted on top of a fuselage and, like the UAS Demonstrator, the entire wing and nacelles will rotate in flight, unlike several competitor designs where only the motor and prop rotate.
First flight of the HEX is anticipated for the end of 2027 or the beginning of 2028.
The HEX will target the regional market along with the largest of Sikorsky’s design aspirations.
“We are studying a nine- to 12-passenger machine that has 400-plus nautical miles of range and that could reach 550 miles, depending on payload,” said Cherepinsky.
At this stage in the research, the Regional Air Mobility Concept is similar to the HEX, albeit with four rotors on the rotor blown wing and a weight closer to 15,000 pounds (6800 kilograms). As this is a concept and market study at this point, there is no timeline for flight or possible entry into service.
The rotor blown wing can be seen at Sikorsky’s booth throughout Verticon 2025.
