The US Defence Advanced Research Projects Agency (DARPA) announced on 24 June 2024, that the Series Hybrid Electric Propulsion AiRcraft Demonstration (Shepard) programme aircraft received its official designation, XRQ-73.
The Series Hybrid Electric Propulsion AiRcraft Demonstration program, known as SHEPARD, has received its official X-plane designation: XRQ-73.
SHEPARD is an “X-prime” program, leveraging the series hybrid electric architecture and some of the component technologies from the earlier AFRL/IARPA Great Horned Owl (GHO) project.
“The idea behind a DARPA X-prime program is to take emerging technologies and burn down system-level integration risks to quickly mature a new missionized long endurance aircraft design that can be fielded quickly,” said Steve Komadina, SHEPARD program manager. “The SHEPARD program is maturing a specific propulsion architecture and power class as an exemplar of potential benefits for the Department of Defense.”
The DARPA team includes members from the Air Force Research Laboratory (AFRL), the Office of Naval Research (ONR), and our warfighters.
The prime contractor for SHEPARD is Northrop Grumman Corporation’s Aeronautics Systems sector in Redondo Beach, CA. Scaled Composites, LLC is a major supplier, along with Cornerstone Research Group, Inc., Brayton Energy, LLC, PC Krause and Associates, and EaglePicher Technologies, LLC.
The XRQ-73 aircraft will be a Group 3 UAS weighing approximately 1,250 pounds. First flight of the XRQ-73 is expected by year-end 2024.
DARPA’s Series Hybrid Electric Propulsion AiRcraft Demonstration (Shepard), XRQ-73 programme aircraft is based on the Great Horned Owl project (GHO)
The GHO project sought to advance the role of UAS in Intelligence, Surveillance and Reconnaissance (ISR) missions by eliminating or reducing the UAS’ acoustic signature while retaining a long-range endurance. To that end the GHO propulsion system quietly generated electrical power from liquid hydrocarbon fuel, either gasoline or diesel, and then used the stored electrical energy to deliver a purely electrically driven quiet flight.
An official designation typically marks an aircraft as having reached a state of development and testing where it is considered ready for operational use, or at least advanced stages of evaluation. However, designation also plays a part in role identification, and in this case, marks the Shepard as an X-plane, an experimental prototype not intended for operations service but instead for use in experimentation and testing purposes, to validate new concepts and technologies.
Top Image: The Series Hybrid Electric Propulsion AiRcraft Demonstration program, known as SHEPARD, sees it’s hybrid-electric uncrewed aircraft system (UAS) receive its official X-plane designation, XRQ-73.
Sources: Press Release; Airforce Technology