Unmanned Aircraft Systems (UAS): Evolving Risks to Large-Scale Public Gatherings

The convergence of several factors has fundamentally altered the unmanned aircraft system (UAS) risk calculus for event security planners. Commercially available drones now offer flight times exceeding 45 minutes, with higher-end systems offering extended endurance, increased speeds, and scalable payload capacities at an affordable price. First-person view (FPV) drones, piloted through real-time video feeds instead of line of sight, have been extensively refined on battlefields in Ukraine and the Middle East, enabling low-cost, high-speed precision strike capabilities increasingly accessible to non-state actors. Concurrently, instructional material for weaponizing commercial drones, including 3D-printed components and improvised payload delivery mechanisms, has proliferated across extremist forums and encrypted messaging platforms.

The federal government’s response reflects the assessed severity of this risk. The December 2025 Federal Communications Commission (FCC) National Security Determination explicitly identifies World Cup and Olympic venues as potential targets for UAS-enabled surveillance, data exfiltration, and disruptive or destructive operations. Executive Order 14305 ("Restoring American Airspace Sovereignty") established a policy framework to secure U.S. airspace against drone threats, with an emphasis on high-risk environments and major events, while the FY2026 National Defense Authorization Act (NDAA) further expanded counter-UAS authorities to state and local law enforcement, reflecting an unprecedented shift driven in part by the World Cup security timeline.

Despite these investments, significant gaps remain. Perimeter fences, magnetometers, bag checks, and credential verification are rendered irrelevant by an airborne threat. Open-air fan zones and similar publicly accessible gathering spaces, which will accommodate large crowds, often lack systematic counter-UAS coverage. The legal and operational authority landscape also remains complex and fragmented. While the SAFER SKIES Act, which was incorporated into the FY2026 NDAA, expanded counter-UAS authorities to include state and local law enforcement, implementation remains limited by a complex legal framework across multiple statutes (e.g., §124n, §130i, §2661), creating challenges for coordination, information sharing, and consistent execution across jurisdictions.

Detection technologies across radio frequency (RF), radar, electro-optical/infrared (EO/IR), and acoustic sensors provide critical awareness but continue to face limitations. These include high false-positive rates in dense urban environments, reduced effectiveness against fiber-optic-controlled (FOC) drones that bypass RF-based detection and jamming, and the persistent challenge of distinguishing hostile intent from legitimate recreational, commercial, or media drone activity.

While the probability of a mass-casualty weaponized drone attack at a large-scale public gathering remains low, the range of plausible UAS threat scenarios, ranging from isolated overflights causing crowd disruption to coordinated multi-venue operations, is broad, with operationally significant consequences across the spectrum.

Effective counter-UAS security for large-scale events, and more broadly across the homeland, requires an intelligence-driven, layered, and scalable approach. This white paper provides an overview of UAS threats to large-scale public gatherings, including the diverse spectrum of actors with varying motivations, capabilities, and risk tolerances. It further explains how this begins with establishing baseline airspace awareness through cost-effective detection capabilities, such as Remote ID and RF monitoring, and is augmented by more advanced systems, including radar and EO/IR sensors, in high-risk environments. No single technology is sufficient; resilience requires integrating multiple detection modalities with the threat and operational environment.