It's a bird! It's a plane! No ... it's not Superman either!It's a new Defense Advanced Research Projects Agency (DARPA) autonomous flying wing recon hybrid X-plane prototype!Talk about a mouthful!But yeah, it's happening, and it's happening now. The XRQ-73 will boast extra-quiet propulsion and is expected to fly this year, DARPA announced on June 24.According to Air & Space Forces magazine, the new aircraft also goes by the program acronym SHEPARD, for “Series Hybrid Electric Propulsion AiR Demonstration.” And, it is being developed by Northrop Grumman and its Scaled Composites subsidiary. The XRQ-73 will be powered by a hybrid electric system which converts fuel to electric power and is part of DARPA’s X-prime program.The program builds upon hybrid technologies and other components developed as part of the “Great Horned Owl” predecessor project run by the Air Force Research Lab and the Intelligence Advanced Research Projects Agency, Air & Space Force reported.The Office of Naval Research and AFRL are also partners on SHEPARD, along with Cornerstone Research Group, Inc.; Brayton Energy, LLC; PC Krause and Associates, and EaglePicher Technologies, LLC.Coming in at 1,250 pounds, the XRQ-73 is described as a “Group 3” uncrewed aerial system. Group 3 UAS also fly below 18,000 feet, and between 100 and 250 knots airspeed. The then-unnamed aircraft was expected to fly in calendar 2023, but DARPA did not offer an explanation as to why it did not.DARPA said the XRQ-73 could be “rapidly fieldable.” In other words, stay tuned.The SHEPARD vehicle will have an “operationally representative fuel fraction and mission systems, while staying below the Group 3 UAS weight limit,” DARPA said on its website.An IARPA program briefing slide from 2011 noted that noise is the “number-one signature” issue for low-flying UAS. A hybrid power approach was chosen to eliminate gearbox noise on the GHO. .Scaled Composites is doing the fabrication; Northrop and its Scaled subsidiary are also working on the Defense Innovation Unit/Air Force Blended Wing Body demonstrator, seen as a potential prototype for a stealthy transport.SHEPARD program manager Steve Komadina said in a DARPA press release that the idea behind DARPA’s 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.”In short, it will be state-of-the-art UAS, that will be quiet and have a long range — two things the military wants.Unlike many of the existing U.S. flying wing drone designs, the XRQ-73 has a pair of air intakes on top of the central section of the fuselage instead of just one.The SHEPARD uncrewed aircraft’s two intakes flank a fairing in the center. This is a distinctly different configuration from the one seen in the first public rendering DARPA put out for the program, which had four separate intakes, The War Zone reported.Beyond it featuring a hybrid-electric propulsion system, details about how the XRQ-73 is powered are limited. Hybrid-electric propulsion systems combine fuel-powered engines and electric motors offering improved fuel economy and other benefits.The addition of batteries further allows for operation in a quieter all-electric mode.We do know that the preceding XRQ-72A featured two multi-sectioned inlets at the front of its fuselage that fed air, in part, to two fuel-powered generators.Those generators then provided electric power to four ducted fan propulsors mounted on top of the rear of the central fuselage.The importance of UAS's in today's battlespace, took on new life from lessons learned in the Russia-Ukraine conflict.The Ukrainian battlespace features the most intensive use of drones in a military conflict in history, marking a shift in warfare tactics and technology.According to The European Council on Foreign Relations, surveillance and reconnaissance are the most natural uses of drones.All drones carry photo, video, or other data collection sensors, which allow forces to locate enemy bases, observe troop movements, and choose targets.Closely linked to surveillance is the ability of drones to document attacks, which can also provide useful material for propaganda purposes.Finally, drones are used to help direct and conduct strikes. At the beginning of the war, Ukrainian forces used armed military drones such as the TB2 to target the Russian convoy headed for Kyiv.A TB2 drone may also have been used to distract the defences of the Russian flagship Moskva while naval missiles attacked and ultimately sank it. Intelligence gathered by drones is also used to direct artillery and other strikes.Officials said the newly designated XRQ-73 hybrid UAS will be a new mission-focused aircraft design, which DARPA is aspiring to have in the air within the next few months.The XRQ-73 is just one of the X-planes DARPA is currently developing.In May, DARPA revealed new imagery of the SPRINT program’s X-plane, which is presently advancing toward its preliminary design phase.The SPRINT X-plane is intended to be a proof-of-concept technology demonstrator and its flight test program seeks to validate enabling technologies and integrated concepts that can be scaled to different size military aircraft.The X-1 nicknamed Glamorous Glennis and flown by the legendary Chuck Yeager, was the first piloted airplane to exceed the speed of sound and was the first of the X-planes, a series of American experimental rocket planes (and non-rocket planes) designed for testing new technologies.— with files from Air & Space Forces Magazine
