The demonstration successfully paired hydrogen-inflated high-altitude balloons (HABs) with long-endurance unmanned aircraft systems (UAS) to forge a persistent, over-the-horizon (OTH) Intelligent Surveillance, Reconnaissance, and Targeting (ISRT) capability. Powered by the vessel’s onboard electrical systems, this process enables ships to generate hydrogen on demand, thereby reducing their reliance on external fuel resupply. Hydrogen could also enable longer endurance for unmanned systems. When used with high-altitude balloons, hydrogen provides more than just energy, it also generates lift keeping systems airborne. The effort marked the culmination of a four‑year effort backed by the Department of Defense’s Operational Energy Capability Improvement Fund (OECIF) and collaborative partners, including Aerostar and Lockheed Martin.