The Army seeks an Other Transaction Authority prototype project for an Unmanned Aircraft System capable of transporting 20 units of Government-designated blood products per mission in contested/denied environments, with two prototype systems to be developed and delivered. The UAS must meet salient characteristics including a minimum 1.25 ft³ usable payload volume, 25–50 lb payload capacity with at least 35 lb capability, a validated thermal-control container maintaining blood temperature for up to 3 hours across 15°F to 120°F, 30 km one-way radius, 100 km maximum mission distance, 3–6 hours endurance, day/night operations up to 18,000 ft, and U.S. sourcing/SRD flight approval compliance. The prototype period of performance is up to 3 months from award, with fully functional prototype systems—including containers and support equipment—delivered no later than 3 months after award and testing/refinement/documentation coordinated with the Government. Primary delivery and demonstration locations are within CONUS, initially anticipated at Fort Liberty, North Carolina, or another designated XVIII Airborne Corps/medical unit location. The effort is a Firm-Fixed-Price OTA with a single best-value award anticipated, evaluated on price (0.30 weight) and non-price factors, and may lead to a non-competitive follow-on production agreement if the prototype succeeds and demand continues.