The UHBR engine is one of the most fuel-efficient propulsion concepts available today. However, outstanding technical and environmental performances are counterbalanced by severe operational conditions of engine systems. The EVAL project aims to create a demonstrator of a passive cooling system, based on a loop heat pipe (LHP) technology, for efficient thermal management of the UHBR engine bleed system valves exposed to a harsh temperature environment. The EVAL innovation will consist in combination of (i) working fluids able to meet the bleed system valve cooling requirements and aeronautical standards; (ii) EU’s domestic patented technology of evaporator-reservoir modular unit (ALTOM), which makes possible to create superior in thermal performance, compact, lightweight, robust, reliable, easy-to-integrate and still cost-effective thermal management systems; and (iii) innovative technology of LHP charging on-site. The project activities will be concentrated within TRL 4–6 range and will result in a “degraded environment” demonstration of LHP-based passive cooling system capabilities to realize precise thermal management of aircraft engine bleed system valves. In the future, the EVAL thermal management system – playing the role of “enabling technology” – will ensure accurate and precise regulation of the airflow in the UHBR engine, thus, will contribute to reliable and efficient long-term operation of the engine in the whole. Therefore, EVAL project will contribute to high-level impacts expected by the Clean Sky 2 Programme within the key pillars defined in H2020. The project will be realized by R&D teams of (1) National Aerospace University “KhAI” experienced in complex thermal management systems for aerospace and terrestrial applications, and (2) Allatherm SIA, a high-tech SME with key specialization in two-phase heat transfer technologies and devices. Administrative management and coordination will be provided by the Science and Technology Center in Ukraine (STCU). Close collaboration between academia and business will ensure strong innovation and marketing potential of the EVAL project outputs.