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SOF Swarm: Special Operations Air Assets and Autonomous Systems

  • Published
  • By Capt Dick D. Yount

Introduction

Vignette: Over the past few weeks, a special operations task force has been employing its intelligence, surveillance, and reconnaissance (ISR) assets in the search for a known weapons facilitator and financier for a violent extremist organization in West Africa. With additional confirmation from sources on the ground, the task force believes they have narrowed down the home of the individual to a set of buildings in a small village and have assembled an assault force in an effort to capture him. An AC-130J and MQ-9 Reaper are overhead to support the operation. Due to low ambient noise, the ground force commander that has the AC-130J and MQ-9 are seven and five nautical miles away prior to actions on in hopes of not spooking the high-value individual (HVI), severely degrading sensor capabilities. Additionally, intermittent low cloud ceilings are passing through the target area around 8,000 feet, further limiting the aircraft’s ability to maintain situational awareness on the target area. Concern for the safety of the ground force drives the Joint Terminal Attack Controller to request the AC-130J to descend below the weather and push into the target area early. Due to the poor battlespace picture and suboptimal sensor operations, an unspotted force maneuvers on and engages the friendlies. The audio signature of the gunship and small arms fire alert the HVI of the impending assault and makes his escape. The MQ-9 is unable to track the getaway due to weather, the mission is aborted, and the assault force prepares for Exfil.

Given 20 years of Special Operations Forces (SOF) centric warfare, enemies of the United States have become savvy to many of our tactics, techniques, and procedures (TTPs). Simply put, if there are airplanes overhead, it’s time to lay low. ISR and close air support integration in SOF operations are critical to mission success, but, as stated in the vignette, adjustments to operations force SOF air assets to maintain positions of unoptimized situational awareness at different phases of action. The past decade has seen tremendous leaps forward in the development of autonomous system technologies. Unmanned aerial systems (UAS) are increasing in use in both commercial and military applications. Just as with most technologies, UAS are becoming smaller, more capable, and more accessible. The United States military is already well into research and testing micro-UAS system employment, enhancing the system's capabilities using swarm technologies and datalink capabilities in a variety of ways to gain a decisive advantage over adversaries.1 United States Special Operations Command (AFSOC) is involved in the undertaking as well, identifying that Special Operations air assets developing the TTPs to employ air-launched UAS will synergistically enhance battlespace awareness and mission effectiveness while reducing the risk to force for both air and ground assets. This paper will assess the current progress of such UAS development, identify barriers, and recommend long-term solutions to keep SOF both safe and relevant in its current and future mission sets.

Tactical Off-Board Sensors

The idea of special operations aircraft deploying UAS systems is not new. In 2017, AFSOC alongside Air Force Research Laboratories began researching the concept of tactical off-board sensors (TOBS).2 AC-130Js, for example, carry and employ many of their precision-guided munitions (PGM) via common launch tubes (CLT). CLTs are composite structures six inches in diameter by four feet long, usually mounted internally to an aircraft collared to the fuselage for the ejection of smaller PGMs such as the AGM-176 Griffin missile. The CLT is also equipped with lugs as well, allowing for external mounting on aircraft such as the MQ-9. The TOBS concept essentially involves taking Micro-UAS systems and configuring them for air launch from CLTs. From there, through local datalink networks, an operator aboard the AC-130J would be able to operate the UAS. SOCOM took over as the lead for TOBS research in 2018 and over the past few years has had success in tests involving AC-130J employment.3

The ultimate desired outcome consists of expendable micro-UAS systems, fully integrated into the established command and control networks, capable of providing reliable ISR while operating semi- or fully autonomously. Achieving this level of capability is likely still years away. The primary UAS system that AFSOC and now SOCOM has been experimenting with is the AREA-I ALTIUS-600. The ALTIUS-600 is CLT configurable, boasts a range of 276 miles and over four hours of loiter time with a cruise speed of 60 KIAS, and yields a nose-mounted payload of six lbs capable of executing a variety of mission sets such as ISR, signals intelligence, or potentially kinetic strike capability.4 The ALTIUS as an airframe far exceeds the set user requirements of a two-hour endurance time and 10 nautical mile range. The challenge lies in meeting the target cost per unit and the required sensor capabilities. The ISR sensor costs around $150,000 alone and the target cost for the unit is $100,000, still a steep price to be willing to discard after use. Industry standards have produced higher quality sensors, likely better than what SOCOM is willing to work with. If they are willing to accept the lower resolution and higher pixel failure rates, the price may come down.5 At the end of the day, SOCOM gains one additional sensor on the battlefield and, as the technology and aircraft integration improves, perhaps they will add a couple more to be employed since the AC-130J does not have unlimited launch capability and it can be a safe assumption that assault forces will only be willing to sacrifice PGM fires capability to a certain extent. Near term, these UAS will not be able to provide additional situational awareness much better than what UAS like the Boeing ScanEagle is already performing, and SOCOM needs to look even further into the future.

The Third Offset and Swarm Technology

In his Air Command and Staff College thesis, “An Offset for AFSOF,” Lt Col Chandler Depenbrock explains how the United States military characterizes its major technological advancement gaps in comparison to near-peer adversaries as ‘offsets.’ Assuming an even playing field in other aspects, offsets are the technological edges maintained to give the United States a decisive advantage. The first offset was the introduction of nuclear weapons, which eventually closed as the Soviets and other nations developed their own capabilities. The second offset emerged from stealth and precision-guided munition technology, which of course has also been closed.6 The Defense Innovation Initiative was a memorandum put out in 2014 calling for integrated innovation across multiple spectrums to maintain the advantage over adversaries through the twenty-first century.7 Lieutenant Colonel Depenbrock argues that autonomous systems, along with other innovative technologies, could be the foundation for SOF’s third offset.8

Swarm theory in robotics is the concept where biological behaviors, such as that in social insects like bees, are converted to computer algorithms. Essentially, a single system, such as a UAS, is equipped with the processing, communications, and sensing capabilities to orient itself in relation to other member UAS in the swarm, and then act collectively to achieve a common goal. For the purposes of this paper, swarm behavior can be categorized into three subsets: spatial organization, navigation, and decision-making. Spatial organization behaviors allow the systems to organize themselves in respect to each other and their surroundings, navigation behaviors allow for collective movement within the operating environment, and decision-making behaviors allow for the swarm to act as a whole in making common choices.9 Below are examples of promising US military swarm technology systems that are developing today.

Perdix UAS

Perdix is a small micro-UAS developed by the Massachusetts Institute of Technology alongside the US Strategic Capabilities Office designed to swarm in multiples of tens and hundreds capable of providing low-altitude ISR. An individual system is 6.5 in long with a wingspan of 11.8 inches. It currently boasts an endurance of over 20 minutes at a speed of 40-50 KIAS.10 In 2016, three US Navy F/A-18s successfully released and employed a 103-unit Perdix swarm. The drones were employed from externally mounted flare buckets attached to the aircraft pylons. The swarm shares a common operating system across all the units allowing them to communicate and orient off each other to achieve common tasks. During the tests, the swarm demonstrated behaviors like collective decision-making, adaptive formation flying, and self-healing. Future tests are desired to experiment with Perdix swarms of over 1,000.11

Coyote UAS

The Office of Naval Research’s low-cost UAV swarming technologies program, an initiative working toward similar goals as the Perdix program pursued by Army, Naval, and Marine Corps forces for operations such as counter-UAS, employs Raytheon’s Coyote UAS.12 The Coyote cruises at 55-70 KIAS, has a range of over 50 miles, and an hour of loiter. It can be employed in an ISR or strike role, simultaneously carrying an electro-optical/infrared capable imagery sensor as well as a proximity warhead for counter-UAS missions.13 The Coyote is already configured to be deployed from a CLT. The Coyote has successfully tested operating in swarms of 30 employing similar behaviors as that of the Perdix.14

SOF SWARM

The swarm UAS can be employed in the same way that the AC-130J has been employing the ALTIUS. While the Perdix swarm is currently not CLT compatible, the AC-130J also has external pylons used for larger munitions such as GBU-39s or multiple AGM-114 Hellfires. The flare canisters that deployed the Perdix in the tests, or the development of another compatible capsule, could be mounted to these pylons. From a budget standpoint, the swarm systems above are significantly cheaper than a single ALTIUS that SOCOM is currently pursuing. As compared to the cost of a single ALTIUS-600, a single Coyote UAS is $15,000 or around $500,000 for a 30-drone swarm.15 As it stands, an individual Perdix drone is significantly less. Redundancy is an advantageous capability as well. If any individual member of the swarm fails, the rest maneuver to compensate.

Theoretically, the swarm UAS could provide SOF air assets with a constant 360-degree view of the tactical battlespace while the manned assets are at standoff distances as opposed to an asset only being able to give a target update on a specific side of the orbit. As far as user integration goes, the datalink capability for operation should be integrated into the employing assets mission software, and the user could essentially type in the ISR target MGRS grids and altitude and the UAS will execute the tasking as a swarm. In Admiral William McRaven’s “The Theory of Special Operations,” he highlights several principles critical to the success of special operations missions. Regarding the TOBS concept, the principle of simplicity is key.16 While the technology is advanced, the user integration can be simplified as stated above. Furthermore, TOBs operations do not require swarm technology tomorrow, nor the next day. As previously stated, a single ALTIUS-600 is still an additional sensor, and any additional amount of situational awareness helps. As swarm technologies start developing and integrating to special operations air assets, they likely do not need to be operated in the same numbers idealized strategically by the DOD. SOF likely does not need a 100 or even 30-drone swarm. For example, in the tactical scenario laid out in the vignette, TOBS coverage priorities can be established and used as another local area of coverage. Once the priority is established, whether that sensor be on the friendlies or over the target, that coverage could be accomplished with a 5-10 Coyote swarm.

Conclusion

Tactical off-board sensors can provide SOF forces with a decisive tactical advantage over their adversaries, providing overhead battlespace awareness while manned aerial assets are at standoff distances. The sooner SOCOM can regularly field TOBS the better, even if the micro-UAS’s are more limited in number and more expensive. In the long term, the integration of limited swarm technologies will only increase TOBS capabilities at an efficient cost. Furthermore, as the United States shifts focus from counter-terrorism operations to near-peer conflict, SOF will increasingly face operations in non-permissive environments. Beyond target and weather constraints, penetration of air defenses will likely be required, and infiltrations will require support by conventional forces like SEAD packages. Swarm technology has the potential to give SOF adequate battlespace situational awareness even in these conditions, creating an additional avenue for SOF to remain effective and relevant in future twenty-first century conflicts.

Captain Dick D. Yount

Captain Dick Yount is a U-28A Aircraft Commander assigned to the 319th Special Operations Squadron, Air Force Special Operations Command, Hurlburt Field, Florida. Captain Yount leads a crew of 4 in the Light Tactical Fixed-Wing aircraft designed to operate in and out of austere locations, conducting intelligence, surveillance, and reconnaissance missions in support of special operations forces across multiple Areas of Responsibility. Captain Yount wrote this while attending Squadron Officer School, Maxwell AFB, Alabama.
This paper was written as part of the SOS Air University Advanced Research (AUAR) elective, Ideas and Weapons section.

Notes

1 Jon Harper, “Gunship-Launched Drone Approaches Transition Point,” National Defense Magazine, 19 April 2017, https://www.nationaldefensemagazine.org/.

2 Harper, “Gunship-Launched Drone Approaches Transition Point.”

3 Harper, “Gunship-Launched Drone Approaches Transition Point.”

4 Jason C. Bowman and Michael C. Jagelewski, “Tactical Offboard Sensing (TOBS) Advanced Technology Demonstration: Air-Launched Tube-Integrated UAS,” Altius Vol 2, (Air Force Research Lab Wright-Patterson AFB, OH, 24 February 2020).

5 Harper, “Gunship-Launched Drone Approaches Transition Point.”

6 Chandler Depenbrock, “An Offset for AFSOF: Combining Additive Manufacturing and Autonomous Systems with Swarm Employment,” October 2016,https://apps.dtic.mil/.

7 Charles Hagel, “The Defense Innovation Initiative,” Department of Defense, 15 November 2014, https://archive.defense.gov/.

8 Depenbrock, “An Offset for AFSOF,”; Hagel, “The Defense Innovation Initiative.”

9 Melanie Schranz, et al., “Swarm Robotic Behaviors and Current Applications,” National Center for Biotechnology Information, Frontiers in robotics and AI, 2 April 2020, https://www.ncbi.nlm.nih.gov/.

10 “Perdix Fact Sheet,” Strategic Capabilities Office, 6 January 2017, https://dod.defense.gov/.

11“Perdix Fact Sheet.”

12 Caitlin Irvine, “The American Swarming Programme – Part Two of Three,” The Security Distillery, 12 December 2019, https://thesecuritydistillery.org/.

13 “Coyote Unmanned Aircraft System (UAS),” Army Technology, 2018, https://www.army-technology.com/.

14 Irvine, “The American Swarming Programme,”; “Coyote Unmanned Aircraft System (UAS).”

15 Irvine, “The American Swarming Programme,”; “Coyote Unmanned Aircraft System (UAS).”

16 William H. McRaven, “The Theory of Special Operations” (MA diss., Naval Postgraduate School, 1993), 11.

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