The most significant precursor is DARPA's Air Combat Evolution program, known as ACE. Launched in 2019, ACE set out to develop AI systems capable of performing within-visual-range air combat, essentially dogfighting, against human pilots. The program achieved a series of milestones that would have seemed implausible a decade earlier.
In 2020, an AI agent developed by Heron Systems defeated a human F-16 pilot five to zero in simulated dogfights during the AlphaDogfight competition, a DARPA-organized event designed to benchmark autonomous air combat performance. The AI demonstrated superior reaction time and precision, though it operated in a simplified simulation environment. Later phases of ACE moved from simulation to subscale aircraft, flying AI-controlled jets against each other and against human-piloted aircraft in real-world flight tests at Edwards Air Force Base.
By 2024, DARPA confirmed that an AI-controlled F-16, designated the X-62A VISTA (Variable In-flight Simulator Test Aircraft), had flown autonomous air combat maneuvers against a human-piloted F-16 at Edwards. The AI managed the aircraft's flight controls, executed tactical maneuvers, and responded to the opposing aircraft's actions without human input on stick and throttle. A safety pilot remained in the X-62A cockpit with override capability, but according to DARPA press releases, the AI handled the flying.
The CCA's onboard AI builds on this foundation but extends well beyond dogfighting. The autonomous system must manage navigation, formation keeping, threat detection, sensor employment, weapons delivery, communications, and self-preservation, all simultaneously, and all while coordinating with the human mission commander and other CCAs in the formation.
The command relationship is described as "human-on-the-loop" rather than "human-in-the-loop." The distinction matters. In a human-in-the-loop system, no action occurs without explicit human approval for each step. That model works for an MQ-9 Reaper flying a deliberate surveillance mission, but it is too slow for air combat where decisions must be made in fractions of a second. In the human-on-the-loop model used for CCAs, the human pilot sets the mission objectives, rules of engagement, and boundaries. The AI executes within those boundaries autonomously. The pilot can intervene, redirect, or override at any time, but the AI does not wait for permission before maneuvering, deploying sensors, or taking defensive action.
Whether the AI will have authority to release weapons autonomously remains one of the most sensitive policy questions surrounding the program. Current Department of Defense policy, articulated in DoD Directive 3000.09, requires "appropriate levels of human judgment" in the use of lethal force. The Air Force has not publicly stated whether CCAs will be authorized to fire weapons without real-time human approval, and this decision may vary by mission type, threat environment, and rules of engagement. What is clear is that the technology to do so exists; the question is one of policy, not capability.
Boeing's XQ-58 Valkyrie: The Proof of Concept
The CCA program did not emerge from nothing. Its conceptual and technological foundations were laid by a series of earlier programs, the most important of which was the Kratos XQ-58A Valkyrie.
The Valkyrie first flew in March 2019 at Yuma Proving Ground, Arizona. Built by Kratos Defense under contract to the Air Force Research Laboratory, the XQ-58A was designed as a low-cost, jet-powered unmanned combat air vehicle that could operate autonomously or in coordination with manned fighters. It was intended to demonstrate the core concept that would become CCA: an affordable, attritable drone wingman.
The XQ-58A demonstrated several capabilities critical to the CCA vision. It flew autonomously using pre-programmed mission plans. It launched from a ground-based catapult system, eliminating the need for a runway. It carried internal weapons bays capable of housing small-diameter bombs or air-to-air missiles. And at an estimated unit cost of roughly $2 million to $4 million in production quantities, it proved that a jet-powered combat aircraft could be built at a fraction of traditional fighter costs.