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How the future of Unmanned Military Aircraft is unfolding

The integration of Tactical AI and machine learning in defence projects is enhancing the performance and portability of high-performance capacities across various military platforms

June 3, 2024 By Manish Kumar Jha Photo(s): By Textron Systems,, Aurora Flight Sciences
Aerosonde Mk. 4.8 HQ FTUAS

The Advanced militaries of the world have been increasing efforts to develop trusted autonomy capabilities for their aircraft fleet. For example, leading the race is the US Department of Defense (DoD), working on several programmes to enable the operation of their in-service aeroplanes by using artificial intelligence (AI) and machine learning (ML) software.

Showing the commitment and vision towards autonomous capability, Frank Kendall, the Secretary of the Air Force, recently flew in the front seat of an X-62A Variable In-flight Simulation Test Aircraft in California. The concept called –VISTA—was tested at the Air Force base.

Interestingly, for the entire flight journey, the aircraft was not piloted and remained untouched. In fact, it was aimed to demonstrate various tactical manoeuvres under the control of highly specialised software to test autonomous flying and other advanced capabilities. The project was a result of further collaboration between the Defense Advanced Research Projects Agency (DARPA) and the US Air Force (USAF). This is dubbed as part of DARPA's Air Combat Evolution (ACE) programme.

The US Department of Defense (DoD) is leading efforts to develop trusted autonomy capabilities for their aircraft using artificial intelligence (AI) and machine learning (ML) software.

At the core remains technologies called Tactical AI, a software product and a design philosophy to build high-performance capacities that are portable between platforms.

Another is the unmanned aerial vehicle (UAV) experts at Aurora Flight Sciences which are moving forward with developing an X-plane to demonstrate enabling technologies in speed and runway independence for future crewed and unmanned aircraft.

The DARPA announced a $25 million order to Aurora Flight Sciences for the Speed and Runway Independent Technologies (SPRINT) programme. Last Year, in the bid for such a scale of autonomous aircraft Aurora managed to present the concept of demonstrator, under the DARPA SPRINT. Other companies taking part in the DARPA SPRINT programme's first phase are Bell Textron; Northrop Grumman Aeronautic Systems and Piasecki Aircraft.

Secretary of the Air Force Frank Kendall flies in the X-62 VISTA in the skies above Edwards Air Force Base, California, May 2. (Air Force photo by Richard Gonzales)

The X-Plane – next-generation autonomous aircraft

Such an advanced level of autonomous systems is based on an X-plane to prove the technologies which could also be tested for aircraft speed. Later it is further aimed to improve, design, build, certify, and fly for the next generation of crewed and unmanned aircraft.

By April 2027, Aurora hopes to have the demonstrator in the air for the first time and validate the enabling technologies at a scaled experimental X-plane demonstrator. After concentrating on conceptual design initially, Aurora engineers will now work on a few chosen X-plane designs before moving on to limited detailed design.

The development of hybrid-electric propulsion systems, featuring distributed ducted fans and tilt-wing technology, is revolutionising electric power generation efficiency and paving the way for advanced vertical take-off and landing (VTOL) capabilities in modern aircraft.

So, the key aspect is to achieve the required speed of 450 to 500 knots, and manoeuvre at such speed with all existing possibilities in terms of testing.

Rather than serving as a pre-production aircraft, the SPRINT X-plane is intended to serve as a proof-of-concept technology demonstrator, allowing the validation of technologies that can be applied to a range of military aircraft sizes.

After the DARPA flight demonstration, the runway-independent SPRINT X-plane should still have useful flight hours and will probably be given to the US Special Operations Command for additional assessment.

Aurora's Latest X-Plane Design Speeds Ahead

The X is also a VTOL X-Plane technology demonstrator intended to achieve a top sustained flight speed of 300 kt-400 kt and Raise aircraft hover efficiency from 60 per cent to at least 75 per cent.

It also aimed to present a more favourable cruise lift-to-drag ratio of at least 10, up from 5-6 and carry a useful load of at least 40 per cent of the vehicle's projected gross weight of 10,000-12,000 pounds

Together with the members of Aurora's team, Rolls-Royce PLC and Honeywell, the technology demonstrator was designed. With the demonstration aircraft, the Aurora-led team hopes to accomplish several aviation firsts, such as being the first to be designed to demonstrate Distributed ducted fans with hybrid-electric propulsion systems.

US Secretary of the Air Force, participated in a test flight of the X-62A Variable In-flight Simulation Test Aircraft, demonstrating autonomous flying capabilities without pilot intervention.

This is groundbreaking aviation according to a senior Honeywell official. What is so radical about such innovation is that it significantly improves electric power-generation efficiency, power density and size. Further as the officials point out it would raise the bar for electric power-generation efficiency that would enable this revolutionary advance in hybrid-electric aircraft propulsion.

It adds a cutting-edge synchronous electric drive setup with high-efficiency vertical takeoff and landing propulsion systems using both tilt-wing and tilt-canard technology for both hovering and fast forward flight.

Future Tactical Uncrewed Aircraft System (FTUAS) Programme

Textron's Future Tactical Uncrewed Aircraft System (FTUAS) Programme is also gearing up for the competition.

FTUAS provides an organic capability to conduct reconnaissance and surveillance operations that collect, develop, and report actionable intelligence, allowing the War fighter to maintain dominance during Multi-Domain Operations. According to the US army, in summary, FTUAS provides transformational capabilities including, VTOL for runway independence, On-The-Move command and control, Soldier led field level maintenance, and enables rapid capability insertions, further allowing the system to keep pace with technology.

Aurora Flight Sciences, under DARPA's SPRINT programme, is developing an X-plane to demonstrate technologies for speed and runway independence in future crewed and unmanned aircraft, with a first flight aimed for April 2027.

After finishing the FTUAS programme, Textron will proceed to improve its suggested design in accordance with the Modular Open System Approach (MOSA) standards set forth by the Army, culminating in a critical design assessment. Textron Systems is providing the Aerosonde Mk. 4.8 Hybrid Quad (HQ) unmanned aircraft system (UAS) for the programme.

How far such initiates are able to realise the steps towards a robust system? Here, for example, Aerosonde HQ has already proven its interoperability in addition to achieving the crucial operational agility. So far, with over 35 separate payload integrations and the ability to carry multiple payloads simultaneously, the Aerosonade is rapidly deploying and testing its data-proven autonomous elements.

Textron's Future Tactical Uncrewed Aircraft System (FTUAS) programme aims to provide advanced reconnaissance and surveillance capabilities with VTOL for runway independence and on-the-move command and control.

The multi-payload capabilities of the Aerosonde Mk. 4.8 HQ, designed for the Army's Brigade Combat Teams (BCTs), provides these units at the tactical edge with more options when it comes to outfitting the sensors required for the task and the surrounding conditions. The statement from their representatives claims that Textron Systems' ongoing commitment to integrating and showcasing payloads offers a low-risk way to satisfy the Army's requirements.

In a statement, Wayne Prender, Senior Vice President of Air Systems at Textron explained that with 30+ years of UAS experience accumulated over three million flight hours, they have established a mature, reliable and ready ecosystem to support our Army customer. He further outlines that the system is designed in a way to be adaptable so that as technology evolves, the Aerosonde UAS can support the soldiers not only in the near term but in the future as well.

As to the official announcement, the Aerosonde HQ platform is capable of handling several missions and is based on a family of systems that have accumulated more than 6,00,000 flying hours. The SWAP profile of the aircraft is designed to maximise its capabilities, including wide-area surveillance, full-motion video capture in both day and night, communications relay, signals intelligence, and more.


Manish Kumar Jha is a Consulting & Contributing Defence Editor for SP's Aviation, SP's Land Forces and SP's Naval Forces and a security expert. He writes on national security, military technology, strategic affairs & policies.