General Atomics Aeronautical Systems, Inc. (GA-ASI) is poised to begin the flight-testing phase on the Defense Advanced Research Projects Agency’s (DARPA) LongShot program. Begun in 2020, General Atomics was competitively awarded a contract to develop DARPA’s concept for disruptive air combat operations through demonstration of an air-to-air weapons capable air vehicle. The concept seeks to significantly increase engagement range and mission effectiveness of current 4th generation fighters and air-to-air missiles.
Over the last three years, GA-ASI has iterated on numerous vehicle designs to optimize performance and will complete the design enroute to flight testing in 2024. The testing will validate basic vehicle handling characteristics and lay the foundation for follow-on development and testing.
«We are extremely excited to get in the air!» said Mike Atwood, Vice President of Advanced Aircraft Programs at GA-ASI. «Flight testing will validate digital designs that have been refined throughout the course of the project. General Atomics is dedicated to leveraging this process to rapidly deliver innovative unmanned capabilities for national defense».
Lockheed Martin has won a contract from the Defense Advanced Research Projects Agency (DARPA) to develop and demonstrate a nuclear-powered spacecraft under a project called Demonstration Rocket for Agile Cislunar Operations (DRACO). The project will represent a rapid advancement in propulsion technology to benefit exploration and national defense.
DARPA partnered with NASA’s Space Technology Mission Directorate on the DRACO project, as both agencies will benefit from this leading edge technology. The in-space flight demonstration of a nuclear thermal rocket engine vehicle will take place no later than 2027.
Faster, Farther, More Agile
Chemical propulsion engines have long been the standard for spaceflight, but for humans to travel to Mars, they will need much more powerful and efficient propulsion. Nuclear Thermal Propulsion (NTP) engines offer thrust as high as conventional chemical propulsion with two-to-five times higher efficiency, which means the spacecraft can travel faster and farther and can significantly reduce propellant needs. They also enable abort scenarios on journeys to Mars that are not possible with chemical propulsion systems.
«These more powerful and efficient nuclear thermal propulsion systems can provide faster transit times between destinations. Reducing transit time is vital for human missions to Mars to limit a crew’s exposure to radiation», said Kirk Shireman, vice president of Lunar Exploration Campaigns at Lockheed Martin Space. «This is a prime technology that can be used to transport humans and materials to the Moon. A safe, reusable nuclear tug spacecraft would revolutionize cislunar operations. With more speed, agility and maneuverability, nuclear thermal propulsion also has many national security applications for cislunar space».
Safe and Efficient Nuclear Tech
An NTP system uses a nuclear reactor to quickly heat hydrogen propellant to very high temperatures and then funnels that gas through the engine nozzle to create powerful thrust. The fission-based reactor will use a special High-Assay Low-Enriched Uranium, or HALEU, to convert the cryogenic hydrogen into an extremely hot pressurized gas. The reactor will not be turned on until the spacecraft has reached a nuclear safe orbit, making the NTP system very safe.
Lockheed Martin has partnered with BWX Technologies to develop the nuclear reactor and produce the HALEU fuel.
«In the past several years, BWXT has been maturing its nuclear thermal propulsion fuel and design, and we are excited to further expand into space with our ability to deliver nuclear products and capabilities to the U.S. Government», said Joe Miller, BWXT Advanced Technologies LLC president. «We look forward to building the reactor and manufacturing the fuel at our Lynchburg, Virginia, facilities».
While nuclear systems are an emerging field, Lockheed Martin has a long history and expertise in nuclear controls and has built many of NASA’s radioisotope thermoelectric generators for NASA’s planetary missions. Lockheed Martin has also invested heavily in cryogenic hydrogen storage and transfer. This key technology will be needed in deep space exploration not only for NTP, but for conventional propulsion systems.
Northrop Grumman Corporation has been awarded a contract by the Defense Advanced Research Project Agency’s (DARPA) Tactical Technology Office to design an autonomous Vertical TakeOff and Landing (VTOL) uncrewed aircraft system capable of operating from a moving Navy ship at sea.
The AdvaNced airCraft Infrastructure-Less Launch And RecoverY (ANCILLARY) demonstrator will be designed as a cost-efficient, multiple-mission capable vehicle built on an agile platform that is runway independent.
Northrop Grumman’s ANCILLARY demonstrator will be capable of carrying a large 60-pound/27.2-kg sensor payload with greater endurance of 20 hours’ time on station and mission radius range of 100 nautical miles/115 miles/185 km, which is more than current systems, without using significant additional infrastructure aside from what is on board the air vehicle. The system will also have capability to land on a ship in adverse weather conditions.
The aircraft will be capable of performing intelligence, surveillance, reconnaissance and targeting missions, and supporting expeditionary missions for special operations forces and logistical missions with significant affordability impacts for ship-to-shore transition of parts and supplies.
Tim Frei, vice president, research and advanced design, Northrop Grumman: «In collaboration with DARPA, Northrop Grumman will work to significantly enhance how future autonomous vertical lift aircraft will operate at sea and ashore. The ANCILLARY program enables us to combine our digital engineering expertise with extensive knowledge and insights from past successes in developing and operating uncrewed vertical lift aircraft for the U.S. Navy».
Details on DARPA ANCILLARY
DARPA’s ANCILLARY program aims to develop and flight demonstrate an X-plane with the critical technologies required for a leap-ahead in long endurance, VTOL Unmanned Air System (UAS) performance. The UAS would be able to launch and recover from ship flight decks and small austere land locations in adverse weather without additional infrastructure equipment, thus enabling expeditionary deployments. Unlike large VTOL systems, the small UAS size would allow many aircraft to be stored and operated from one ship creating a tactical beyond-line-of-site, multi-intelligence sensor network capability.
Two teams – General Atomics working with Maritime Applied Physics Corporation and Aurora Flight Sciences working with Gibbs & Cox and ReconCraft – will develop designs for DARPA’s Liberty Lifter Seaplane Wing-in-Ground Effect full-scale demonstrator. The Liberty Lifter program aims to demonstrate a leap-ahead in operational capability by designing, building, floating, and flying a long-range, low-cost X-Plane capable of seaborne strategic and tactical heavy lift.
The planned Liberty Lifter demonstrator will be a large flying boat similar in size and capacity to the C-17 Globemaster III transport aircraft. Goals include takeoff and land in Sea State 4, sustained on-water operation up to Sea State 5, and extended flight close to the water in ground effect with the capability to fly out of ground effect at altitudes up to 10,000 feet/3,048 m above sea level.
«We are excited to kick off this program and looking forward to working closely with both performer teams as they mature their point-of-departure design concepts through Phase 1», said Defense Advanced Research Projects Agency (DARPA) Liberty Lifter Program Manager Christopher Kent. «The two teams have taken distinctly different design approaches that will enable us to explore a relatively large design space during Phase 1».
The General Atomics team has selected a twin-hull, mid-wing design to optimize on-water stability and seakeeping. It employs distributed propulsion using twelve turboshaft engines.
Aurora Flight Sciences point-of-departure design more closely resembles a traditional flying boat, with a single hull, high wing and eight turboprops for primary propulsion.
During Phase 1, DARPA will work with both performer teams and Department of Defense (DoD) stakeholders to refine the Liberty Lifter designs with particular attention to operational needs and operating concepts. The Phase 1 contract awards are for an 18-month period of performance with six months of conceptual design work and nine months of design maturation culminating in a preliminary design review. There will be an additional three months for manufacturing planning and test/demonstration planning reviews.
As scheduled, Phase 1 will transition into Phase 2 in mid-2024 with continued detailed design, manufacturing, and demonstration of a full-scale Liberty Lifter X-Plane. DARPA anticipates teaming with one or more DoD Service and international partners for those activities and further development of the Liberty Lifter concept into an operational vehicle.
The joint Defense Advanced Research Projects Agency (DARPA) and U.S. Air Force Hypersonic Airbreathing Weapon Concept (HAWC) completed yet another successful flight test. The Lockheed Martin version of the missile, with its Aerojet Rocketdyne scramjet, capped a program that accomplished all of its initial objectives. It was the final flight test for HAWC, which is providing critical data to inform Air Force Research Laboratory (AFRL) hypersonic technology maturation efforts.
«This month’s flight added an exclamation point to the most successful hypersonic airbreathing flight test program in U.S. history», said Walter Price, an Air Force deputy for the HAWC program. «The things we’ve learned from HAWC will certainly enhance future U.S. Air Force capabilities».
The Lockheed Martin missile again flew at speeds greater than Mach 5/3,836 mph/6,174 km/h, higher than 60,000 feet/18,288 m, and farther than 300 nautical miles/345 miles/555.6 km. This latest flight demonstrated improved capabilities and performance. The nation’s hypersonic portfolio now has two feasible hypersonic airbreathing missile designs (Lockheed Martin and Raytheon) to improve and mature in the future.
«The HAWC program created a generation of new hypersonic engineers and scientists», said Andrew “Tippy” Knoedler, the HAWC program manager. «HAWC also brought a wealth of data and progress to the airbreathing hypersonic community. The industry teams attacked the challenge of scramjet-powered vehicles in earnest, and we had the grit and luck to make it work».
Even though the HAWC program has executed the final phase of the program, there is still data to analyze and more opportunities to mature the technology. DARPA plans to continue that maturation in the More Opportunities with HAWC (MOHAWC) program by building and flying more vehicles that build upon HAWC’s advances. Those missiles will expand the operating envelope of the scramjet and provide technology on-ramps for future programs of record.
«We had our share of difficulties», said Knoedler. «Through a pandemic, a strained supply chain, and atmospheric rivers, our industry partners forged ahead, mitigating the risks where they could and accepting others. They delivered on their promises, proving the feasibility of the concept».
Defense Advanced Research Projects Agency (DARPA) has selected Aurora Flight Sciences to move into the detailed design phase of the Control of Revolutionary Aircraft with Novel Effectors (CRANE) program. This follows successful completion of the project’s Phase 1 preliminary design, which resulted in an innovative testbed aircraft that used Active Flow Control (AFC) to generate control forces in a wind tunnel test. Phase 2 will focus on detailed design and development of flight software and controls, culminating in a critical design review of an X-plane demonstrator that can fly without traditional moving flight controls on the exterior of the wings and tail.
The contract includes a Phase 3 option in which DARPA intends to fly a 7,000-pound/3,175-kg X-plane that addresses the two primary technical hurdles of incorporation of AFC into a full-scale aircraft and reliance on it for controlled flight. Unique features of the demonstrator aircraft will include modular wing configurations that enable future integration of advanced technologies for flight testing either by DARPA or potential transition partners.
«Over the past several decades, the active flow control community has made significant advancements that enable the integration of active flow control technologies into advanced aircraft. We are confident about completing the design and flight test of a demonstration aircraft with AFC as the primary design consideration», said the CRANE Program Manager Richard Wlezien. «With a modular wing section and modular AFC effectors, the CRANE X-plane has the potential to live on as a national test asset long after the CRANE program has concluded».
The AFC suite of technologies enables multiple opportunities for aircraft performance improvements, such as elimination of moving control surfaces, drag reduction and high angle of attack flight, thicker wings for structural efficiency and increased fuel capacity, and simplified high-lift systems.
«Thanks to a variety of innovative participants, the CRANE program has significantly advanced the state of the art of multiple active flow control technologies», said Wlezien. «We are uniquely positioned to build on those achievements by evaluating a wide range of relevant technologies during our planned X-plane flight tests».
Sikorsky, a Lockheed Martin company and the Defense Advanced Research Projects Agency (DARPA) have successfully demonstrated to the U.S. Army for the first time how an uninhabited Black Hawk helicopter flying autonomously can safely and reliably perform internal and external cargo resupply missions, and a rescue operation.
Performed October 12, 14 and 18 as part of the U.S. Army’s Project Convergence 2022 (PC22) experiment, the flights show how existing and future piloted utility helicopters could one day fly complex missions in reduced crew or autonomous mode. This would give Army commanders and aviators greater flexibility in how and when aircraft and pilots are used, especially in limited visibility or contested environments.
Why It Matters
Sikorsky is partnered with DARPA to develop autonomy technology that will exponentially improve the flight safety and efficiency of rotary and fixed-wing aircraft. Sikorsky’s autonomy system, known as MATRIX technology, forms the core of DARPA’s ALIAS (Aircrew Labor In-cockpit Automation System) project.
«We believe MATRIX technology is ready now for transition to the Army as they look to modernize the enduring helicopter fleet, and acquire Future Vertical Lift aircraft», said Igor Cherepinsky, director of Sikorsky Innovations. «In addition to increasing flight safety and reliability, MATRIX technology enables survivability in high tempo, high threat 21st Century Security environments where Black Hawk helicopters operate today, and DEFIANT X and RAIDER X helicopters could operate in the future. Uncrewed or reduced crewed helicopters could safely perform critical and lifesaving missions day or night in complex terrain and in contested battlespace».
The Yuma Details
During PC22 Technology Gateway, the Sikorsky and DARPA team showed how the optionally piloted Black Hawk helicopter with no humans on board can deliver a large quantity of blood product unharmed by flying low and fast above ground level using the terrain to mask its signature; resupply troops with an external load; and re-route mid-flight to evacuate a casualty.
To begin the flight demonstrations, pilots flew and landed the Black Hawk aircraft, then activated the MATRIX system to give full control to the flight computer. When the pilots exited, the helicopter autonomously completed the following mission demonstrations:
Long-endurance Medical Resupply: The Black Hawk aircraft flew 83 miles/133.6 km while loaded with 400 units of real and simulated blood – totaling 500 pounds/277 kg. On reaching 40 miles/64.4 km from its initial take-off point, the helicopter descended into a valley as low as 200 feet/61 m above ground level at 100 knots/115 mph/185 km/h.
Cargo Delivery and Casualty Evacuation (combined mission): The helicopter lifted off with a 2,600-pound/1,179-kg external load attached to a 40-foot/12-meter sling, and flew at 100 knots/115 mph/185 km/h for 30 minutes toward a designated landing zone. While in flight, the helicopter was redirected, simulating a scenario in which a threat needed to be neutralized near the primary landing site. Sikorsky demonstrated how a ground operator with a secure radio and tablet can take control of the uncrewed helicopter, command it to release its sling load, and then land to evacuate a casualty from a nearby location. Once the manikin on a litter was secured inside the cabin, the ground operator launched the aircraft. During the return flight, a BATDOK health monitoring device integrated with the helicopter’s communications system relayed the patient’s vitals in real-time to a ground-based medical team.
The PC22 demonstrations were the second set of uninhabited Black Hawk flights this year. Sikorsky and DARPA will continue to work toward the transition of this technology for military operations, such as aircrew support and operations, logistics and medical resupply, casualty evacuation, and commercial applications such as firefighting, cargo and urban air mobility.
Sikorsky and DARPA Autonomous Black Hawk Flies Logistics and Rescue Missions Without Pilots on Board
Radar systems have seen many technology improvements in apertures (antennas) and associated hardware and software since the nascent operational versions in World War II. What hasn’t changed significantly over the decades, however, is that radars still use linear signal processing between the aperture and the detector. In the 1940s linear radar signal processing used vacuum tubes and analog circuits, while current radars accomplish linear signal processing digitally with microchips and software.
With the Beyond Linear Processing (BLiP) program, DARPA’s goal is to improve radar performance by applying innovative signal processing methods. BLiP will leverage high-power computer processing to explore new, non-linear and iterative signal processing techniques that could lead to lighter, smaller, and less expensive – but equally capable – radar systems. If successful, BLiP would enable the same radar performance achieved on large platforms today on much smaller sea, air, and ground platforms.
«A lot of radar improvements over the past 30 years have focused on growing the size of the aperture for greater sensitivity or increasing transmitter power», said Frank Robey, BLiP program manager in DARPA’s Strategic Technology Office. «Those are important, but if we want to shrink aperture size by 50% and still get the same radar performance then we need to disrupt the linear signal processing paradigm. With the tremendous increases in computer processing power available today, we can take a fresh look at radar signal processing and explore iterative, leap-ahead techniques».
BLiP will address the current immaturity of non-linear and iterative signal processing methods. Over the course of the two-year program, end-to-end radar signal processing chains will be developed, analyzed, implemented and tested – initially through non-real-time laboratory testing and culminating in real-time implementation and full-scale field testing using an operational National Weather Service radar. Key technical challenges for BLiP will be the development, understanding, and optimization of the signal processing chain, and the practical aspects of implementing BLiP algorithms using real-time, high-performance processing.
A Proposers Day for interested proposers is being held on October 28. The BLiP Broad Agency Announcement solicitation provides full program details for submitting an abstract and/or proposal.
DARPA is working on the next leap forward in energy distribution by leveraging wireless power beaming to create a dynamic, adaptive, speed of light wireless energy web. The goal of the Persistent Optical Wireless Energy Relay (POWER) program is to design and demonstrate airborne optical energy relays. These relays are a critical component necessary to allow ground-sourced lasers to be coupled with high-altitude, efficient long-range transmission. Additionally, such relays will enable future multi-path wireless energy networks.
«This is the internet for energy – harnessing resilient, multipath networks to flow energy from abundant sources to energy-starved consumers», said Colonel Paul Calhoun, POWER program manager in DARPA’s Tactical Technology Office. «The military faces particularly acute energy challenges, which are driving this innovation. We often must operate far from established energy infrastructure and rely on liquid fuels that require precarious supply lines».
Current military platforms that require long range, endurance, or significant weapons delivery capability must be physically large to carry the stored energy needed to complete a mission as liquid fuel. A wireless power transfer network transforms platforms into conduits rather than containers, which enables small inexpensive platforms with significant capabilities such as unlimited range or endurance.
Power beaming may sound exotic, but it is the exact same physics used in wireless communication. «You need a power source; you convert that power to a propagating wave, typically electromagnetic, send it through free space, collect it in through an aperture, and then convert it back to electricity», said Calhoun.
Conversion efficiencies remain a challenge, though. In a multi-hop network, converting from a propagating wave back to electricity and back to propagating wave at each node quickly accrues unacceptable losses. Each one of those conversions is relatively inefficient and multiplying them across a chain is impractical.
«The POWER program will develop efficient power beaming relays that redirect optical energy transmissions while maximizing beam quality at each point along the way, selectively harvesting energy as needed», said Calhoun. «It is a three-phase development effort, culminating in a compelling energy relay flight demonstration».
History has shown energy transport breakthroughs like the Roman roads, railroads, mechanized warfare, and air-refueling tankers that more rapidly and resiliently flow energy through the battlespace give a decisive military advantage. «We believe the next energy revolution will be enabled by the wireless energy web», said Calhoun. «It will dramatically compress transport timelines and resiliently provide distributed energy to consumers in air, on land, on the sea, undersea, and in space».
DARPA’s AdvaNced airCraft Infrastructure-Less Launch And RecoverY X-Plane program, nicknamed ANCILLARY, aims to develop and flight demonstrate critical technologies required for a leap ahead in Vertical TakeOff and Landing (VTOL), low-weight, high-payload, and long-endurance capabilities. The goal is to build a plane that can launch from ship flight decks and small austere land locations in adverse weather without launch and recovery equipment typically needed for these systems.
«The ability for the warfighter to deploy and retrieve such systems in challenging conditions without reliance on infrastructure would minimize personnel, costs, and vulnerability during sensitive operations», said Steve Komadina, the DARPA program manager for ANCILLARY.
A large non-traditional commercial industry base has fueled recent VTOL research investments and advanced controls leading to innovative vehicle configurations spanning size, weight, power, and cost. Advancements in small propulsion systems, high capacity low weight batteries, fuel cells, materials, electronics, and low-cost additive manufacturing can now enable new architectures and designs to be explored in this trade space.
«ANCILLARY plans to use a multi-disciplinary approach that will bring together developments in advanced control theory, aerodynamic modelling, and advanced propulsion to solve a combination of challenging design objectives», said Komadina. «The upcoming Proposers Day and Expo on September 20, 2022, will not only bring together traditional aircraft manufactures, but also non-traditional military contractors that have been investigating commercial VTOL solutions».
Industry and academic technologists and researchers who could supply needed component and manufacturing techniques are encouraged to attend.
AdvaNced airCraft Infrastructure-Less Launch And RecoverY (ANCILLARY)