By Col. Mark Gunzinger, USAF (Ret.) who is the director for future aerospace concepts and capabilities assessments at the Mitchell Institute for Aerospace Studies and Lukas Autenried, senior analyst at the Mitchell Institute. The full report can be found at www.mitchellaerospacepower.org.
Over the next decade, the U.S. Air Force must find a way to maintain readiness, modernize its aging aircraft inventory, and grow to 386 operational squadrons. The reasons are clear: Threats are on the rise, and U.S. leaders need new options empowered by next-generation combat air forces with increased capacity. A flat or declining defense budget could deprive the Air Force of the resources it needs to pull off this balancing act and force harmful compromises that increase the risk of mission failures.
Historically, USAF used two approaches to modernize and grow its capacity: First, it bought new, more advanced aircraft with life cycles spanning decades; second, it procured larger quantities of single-use capabilities such as precision-guided munitions, which it expends to achieve operational effects.
There will soon be a third choice. The Air Force is now developing a family of unmanned aerial vehicles (UAVs) designed to fly a limited number of sorties and cheap enough to use in threat environments where the risk of attrition is too high for manned aircraft. These “attritable/reusable” (A/R) UAVs will employ artificial intelligence-enabled autonomy to team with other aircraft to conduct multiple missions. Procuring low-cost A/R UAVs to complement required high-end capabilities such as F-35As and B-21s is an affordable way to grow USAF’s combat capacity while balancing other requirements. A/R UAVs that do not require airfields for launch and recovery would also help the Air Force remain an “inside force” capable of generating combat power from dispersed expeditionary locations within range of Chinese or Russian anti-access/area-denial (A2/AD) threats. This will help change adversary defense calculations and impose costs on opponents—to the advantage of U.S. interests.
What Are Attritable/Reusable UAVs?
A/R UAVs are low-cost, modular, artificial intelligence (AI)-enabled unmanned systems designed to conduct 10 to 100 sorties in contested operational environments. These aircraft will integrate the full spectrum of autonomous capabilities, as the Air Force develops and tests them. They are:
Attritable. Unlike manned fighters and bombers, whose structures, engines, and mission systems must last for decades, attritable UAVs are designed for shorter life spans, as little as months and at most several years. This reduces costs to make them affordable options in high-threat situations where using manned or extremely expensive UAVs would be too risky.
Reusable. Unlike cruise missiles, which are destroyed as they create their desired effects, these multi-use systems can be recovered and then flown again. The XQ-58A Valkyrie A/R UAV can be launched from a relocatable containerized rocket-assisted takeoff assembly and recovered on its return by means of a parachute. A second example: The Defense Advanced Research Projects Agency’s Gremlin A/R UAVs, which aim to be launched and recovered in-flight by appropriately equipped C-130s.
- Low-cost. By leveraging novel and agile manufacturing, modular components, and small and advanced turbine engines, the Air Force aims to greatly reduce the cost and time to manufacture A/R UAVs—as little as a few weeks compared to the 18 months it can take to build a manned fighter. With unit costs of a few million dollars to $20 million, depending on size, range, payload, and mission systems, A/R UAVs will cost a fraction of what it costs to operate a manned fighter, and they will never require depot-level maintenance.
- Modularity. The Air Force’s intent is to field a family of A/R UAVs that share an adaptable open architecture and a “plug and play” design philosophy to execute multiple missions. This modularity will drive down costs, support rapid technology insertion, and allow for in-theater mission changes, such that a system configured with sensors for ISR missions could be quickly reconfigured to conduct electronic attacks or strikes should operational needs change.
- AI-enabled. AI technologies will make A/R UAVs more capable than existing systems, said Gen. James “Mike” Holmes, then the head of Air Combat Command. “The low-cost, attritable aircraft we’ve been looking at will be more autonomous than the RPAs we fly now,” he told Air Force Magazine last spring. “We’ll give it goals, and we’ll tell it about its operating environment, we’ll prioritize targets and actions for it, and, through machine learning, we’ll teach it to make more decisions on its own.”
The Air Force’s Skyborg program is one of three Air Force “Vanguard” science and technology (S&T) programs that are prototyping and experimenting with new weapon systems and operating concepts to “deliver remarkable new capabilities that provide warfighters with superior advantages in the battlefield.” Vanguard status prioritizes Skyborg’s institutional and warfighter support with an eye toward ensuring the autonomous A/R UAV program survives the so-called acquisition valley of death.
Affordable Combat Power
After decades of budget cuts, the Air Force’s combat air forces now lack the capacity to fight a major conflict with a peer adversary such as China, deter threats in other regions, defend the U.S. homeland, and meet other demands articulated in the National Defense Strategy. This includes the ability to attain the air superiority needed to enable joint operations, launch large-scale precision strikes into contested areas, and perform electromagnetic warfare (EW). Recognizing these limitations, a comprehensive Air Force study mandated by Congress concluded the service must grow by about 24 percent—from 312 to 386 operational squadrons—to execute its requirement at a moderate level of risk.
Achieving “The Air Force We Need” will require the Department of Defense (DOD) and Congress to break from traditional resource allocation practices and prioritize Air Force investment to acquire 5th generation F-35s, B-21 bombers, and other advanced aircraft along with this family of low-cost A/R UAVs, which will be most effective when teamed with manned systems. This combination would help create a future force that is more lethal and survivable, and also has combat mass needed to defeat great power aggression. If fielded in large enough quantities, U.S. commanders could simultaneously use A/R UAVs in multiple areas of the battlespace to degrade an enemy’s combat tempo, overwhelm air defenses, and prevent it from concentrating forces.
Responding to A2/AD Threats
Attacking an enemy’s military airbases is one of the most efficient ways to suppress an opposing air force. China and Russia both have thousands of long-range guided missiles that can crater runways, destroy fuel storage and maintenance facilities, and otherwise wreak havoc on U.S. airbase facilities. Large-scale missile attacks such as these on U.S. and allied airbases in the Indo-Pacific and Europe could severely degrade the Air Force’s ability to generate the hundreds of sorties needed to rapidly halt a Chinese or Russian attack.
While there is debate inside the Air Force on how best to adapt warfighting concepts and capabilities to counter this growing missile threat, the ultimate solution will require generating and projecting power from both inside and outside an enemy’s A2/AD threat envelope. Each has inherent advantages, and the benefits of harnessing both approaches are considerable. The Air Force must develop new operating concepts and capabilities to ensure it can continue to fight alongside allies and partners that live inside A2/AD umbrellas.
A/R UAVs that can launch and recover from dispersed expeditionary locations without the need to use an airfield would be an invaluable component of this solution set. The ability to disperse and relocate these aircraft would complicate adversaries’ ability to find, fix, track, and launch effective missile attacks against USAF combat forces. It would also impose new costs on rivals: Instead of concentrating their attacks on a few main operating bases, China and Russia would have to fly more ISR sorties and expend more weapons to find and attack USAF operating locations dispersed across a theater. This would also create uncertainty about their missiles’ effectiveness, and could cause China or Russia to doubt if their campaigns would succeed.
Air-transportable containerized A/R UAVs and their launch systems also would improve USAF resiliency under attack, reducing the logistics footprint required to sustain operations. A recent RAND Corporation study determined that A/R UAVs like the XQ-58A Valkyrie could require “one-fifth the personnel and one-half the equipment” to operate and maintain compared to an F-16 fighter. That translates into only 25-35 percent the number of C-17 airlift missions to deploy the assets, depending on what XQ-58A materiel is prepositioned in a theater. A/R UAVs with ranges of 3,000 nm or more that can launch and recover closer to the joint operating area could also help reduce USAF’s aerial refueling requirements, freeing tanker capacity for other high-priority combat operations.
Operational Risk, Survivability, and Resiliency
In conflicts with a peer adversary, there may be areas of the battlespace where there is significant uncertainty about threats or the risk of attrition is simply too high to use manned aircraft. A/R UAVs would expand theater commanders’ options for highly contested environments. On night one of a conflict with China or Russia, U.S. commanders could use hundreds of A/R UAV variants to locate enemy air defenses, jam air defense command and control nodes, and conduct other missions to improve the survivability of U.S. forces. According to Air Force Assistant Secretary for Acquisition and Logistics Will Roper, Skyborg UAVs will “allow the Air Force to take measured risk with attritable platforms to keep our high-value aircraft in the fight.” Later, as threats are reduced, commanders could shift to using more higher-end A/R UAVs and manned aircraft for operations in contested areas.
To maximize the combat value of A/R UAVs, it may be more cost effective to use them to multiply the kinetic effects that can be created by other combat aircraft that have greater payload capacity, as estimated payloads range from 600 to 1,200 pounds—equivalent to two to four GBU-39 Small Diameter Bombs.
Appropriately equipped A/R UAVs, however, could help backfill USAF’s shortfall in electronic warfare capacity, enhancing the survivability of all U.S. forces within A2/AD envelopes. Using A/R UAVs as remote sensors in contested areas would reduce the need for manned penetrating aircraft to emit radar energy, which can give them away to enemy defenses. Decoy A/R UAVs could be used to stimulate enemy surface-to-air-missile (SAM) systems, causing them to reveal their locations and exposing them to USAF strikes. A/R UAVs equipped with jammers or high-power microwave payloads could conduct electromagnetic attacks on enemy acquisition radars, C2 links, and other air defense components, increasing the survivability of U.S. stealth aircraft and weapons penetrating contested areas.
A/R UAVs should also be explored as part of the Air Force’s Next-Generation Air Dominance family of systems to enable air superiority for U.S. forces. A/R UAVs teamed with manned and unmanned aircraft could increase formations’ overall situational awareness and air-to-air weapon capacity. Leveraging these capabilities, A/R UAVs could help protect aerial refueling tankers and other non-stealth high-value airborne assets, conduct sweeps to defeat enemy fighters that could threaten USAF penetrating strikes, and escort penetrating bombers and fighters.
A/R UAVs would also help create a more heterogeneous future force that is less predictable and more capable of distributed operations. Using many A/R UAVs to conduct highly distributed active and passive sensing operations in contested areas would make USAF’s ISR force more resilient and challenge enemy defenses; instead of targeting a relative few high-value manned ISR aircraft, such as the E-3 Airborne Warning and Control System (AWACS) and E-8 Joint Surveillance and Target Attack Radar System (JSTARS), adversaries would need to defeat hundreds of individual A/R UAVs to degrade U.S. commanders’ battlespace awareness.
Likewise, A/R UAVs could help disaggregate today’s monolithic kill chains, creating “kill meshes” consisting of hundreds of sensors, shooters, and C2 nodes. Each A/R UAV could observe and share sensor data throughout the mesh, enabling penetrating and standoff shooters and other weapon systems as needed. These kill meshes would enable 5th-generation F-35s, B-21s, and other manned penetrators to search for mobile, relocatable targets over larger areas in contested environments.
Finally, this more heterogeneous force with AI-enabled autonomous UAVs would be less predictable, complicating adversaries’ ability to quickly assess and understand the intentions of U.S. commanders, and enabling those commanders to conduct highly distributed, simultaneous offensive operations to overwhelm their adversaries’ capacity to react and defend. Enemies’ defensive challenges would be further complicated by their inability to discern A/R UAVs from manned fighters and bombers, causing them to use high-end defenses to engage lower-end targets.
America’s Air Force is now too small and too old to generate enough combat mass to simultaneously defeat great power aggression and meet other National Defense Strategy requirements. It needs affordable solutions to overcome the damage done by decades of insufficient modernization funding. Low-cost attritable and reusable UAVs present a new class of force multipliers that could help the Air Force balance its requirements and modestly grow its force capacity. Enabled by artificial intelligence and operating without risk to life and limb could change how the Air Force operates.
To build on this concept, the Air Force should:
- Procure low-cost A/R UAVs in significant numbers to increase combat capacity, lethality, and survivability in contested environments.
- View A/R UAVs as complementary, force-multiplying capabilities, rather than replacements for 5th-generation stealth aircraft, which are needed to maintain USAF’s combat advantage over peer adversaries.
- Use A/R UAVs, given their relatively small payloads, for electromagnetic warfare, persistent C2ISR, and other non-kinetic missions that take advantage of their force-multiplying potential.
- Leverage the low cost and modularity of A/R UAVs to rapidly innovate, operationalize advanced technologies, and speed new capabilities to warfighters.
- Experiment with A/R UAVs to allow warfighters to develop concepts for integrating them into operations with other manned and unmanned aircraft.
- Develop operational concepts and the logistical support and other requirements to launch and recover large numbers of A/R UAVs from distributed theater locations without airfields.
Maintaining the Air Force’s current readiness, modernizing for the future, and building The Air Force We Need demands the Air Force seek new, cost-effective alternatives and low-cost A/R UAVs answer that need by improving USAF’s ability to generate and project combat mass inside A2/AD environments. While A/R UAVs should not be seen as a cheaper alternative to F-35A, B-21, and other advanced capabilities, they should be included as part of the next step in the evolution of AI-enabled unmanned systems that can team with advanced manned platforms to achieve decisive effects in the battlespace. Unlike force design approaches that would simply buy more legacy systems with capabilities that are well-known to America’s competitors, A/R UAVs will create new options for U.S. commanders to defeat great power aggression.
The program aims to develop a digital AI architecture and software to support a family of A/R UAVs capable of manned-unmanned teaming operations. Skyborg will also demonstrate technologies and concepts for generating large numbers of sorties without requiring the runways and airbase infrastructure that can be vulnerable to adversary attacks.