CLAIM’s technical work was carried out in two scientific work packages. WP2 (Climate Impact Monitoring) focused on evaluating and recommending climate metrics and methodologies. It began with a review of existing metrics and a structured down-selection procedure, validated through workshops with international stakeholders. Neutrality and robustness emerged as key requirements. Case studies across different aircraft, networks, and fuels highlighted that simplified methods cannot capture location- and altitude-dependent non-CO2 effects, such as contrails and NOₓ-induced ozone, and are therefore unsuitable for detailed technology assessments. Based on this, WP2 proposed a four-layer climate impact assessment framework linking technology, emissions, atmospheric responses, and metrics, which was refined with stakeholder feedback. For the climate metrics, the Average Temperature Response (ATR100) and the efficacy-weighted Global Warming Potential (EGWP100), both evaluated over a 100-year time horizon, were identified as the most suitable choices for the purpose of technology climate impact assessment.
WP3 (Technology Impact Monitoring) performed a technology watch exercise for Clean Aviation. A structured taxonomy and databases of roadmaps and emerging technologies were developed, alongside a review of disruptive aircraft concepts and research infrastructures. Using the WP2 framework, WP3 performed preliminary environmental performance analyses of Clean Aviation-like concepts, including hybrid-electric and short/medium-range aircraft. Mission-based emission inventories were propagated to fleet-level impacts, showing how assumptions on sustainable aviation fuel performance, network choice, and reference aircraft affect climate mitigation potential. Results indicated that new aircraft can approach Clean Aviation targets but remain highly sensitive to underlying assumptions. WP3 also identified capability gaps in Europe for hydrogen and hybrid-electric propulsion, spanning modelling, testing, and system integration.
