Technology Evaluator



What is the value of a new technology developed under the umbrella of Clean Sky?

It is a question which is posed when an idea is proposed at the "Call" stage before a project or sub-programme is accepted into the world of Clean Sky. It is also a question which lingers throughout the life-span of that technology as it transitions through its long lifecycle – through conception, design, demonstration, development, testing, certification, deployment to market, all the way through to end-of-service disposal and recycling of materials. It is a process that can span decades – an ongoing question of value.

The Technology Evaluator (TE) addresses this question by monitoring and assessing the general impact of the technological results arising from all Clean Sky 2 activities and in particular by

  • Describing the environmental and societal impact of the Clean Sky 2 technologies by specifically quantifying the expected improvements in the overall noise, greenhouse gas and air pollutants emissions from the aviation sector in future scenarios in comparison to baseline scenarios 
  • The Set-up of an efficient and effective interface between the Technology Evaluator and the other Clean Sky 2 instruments to strengthen the  exchange, improvement and application of working results and quality management across common ground.
  • Support of the Clean Sky 2 Joint Undertaking bodies by providing adequate and updated information on the impact of the technologies under development

The technology impact assessments in Clean Sky 2 cover environmental and socio-economic impacts with a particular focus on reducing CO2, NOx and noise emissions by 20-30% relative to a “state-of-the-art” aircraft which entered into service in 2014. Where applicable, benefits of Clean Sky 2 demonstrators and technologies will be monitored against well-defined environmental targets and socio-economic targets of the ACARE Flightpath 2050 and the corresponding goals outlined in the Strategic Research and Innovation Agenda (SRIA).

Clean Sky 2 technologies will generally be considered in the form of “concept aircraft models” and related impacts will be assessed on three levels. The levels and the assessment categories are defined as follows:

At "Mission Level" (micro level) the environmental and the socio-economic assessment dimension will be covered. In respect of the environmental assessment dimension, the future concept aircraft models and their respective reference aircraft counterparts which relate to aircraft having entered the market in 2014 will be compared for single representative missions to determine the environmental benefit of the Clean Sky 2 technologies. Criteria will be oriented around noise on the ground (measured in dB levels), as well as CO2 and NOX emissions. Also planned is consideration of SOx, VOC and particles to complete the focus on climate impact analyses. In terms of the socio-economic dimension, the Technology Evaluator will cover mobility and connectivity impacts at mission level up to a certain extent by determining rotorcraft mission productivity improvements (e.g. travel time savings through higher cruise speed). Life cycle assessments of the socio-economic impact at single aircraft level will be performed by Eco-Design and mark a separate assessment approach at a different level of granularity and with a different focus. For the Technology Evaluator assessment tasks, the mission level assessment horizon is benchmarked against year 2014 and the future assessment years 2025, 2035 and 2050.

At "Airport Level" (meso level), Clean Sky 2 concept aircraft insertion modelling into the global fleet is used to derive airport fleet traffic scenarios. In parallel to mission level, this will be carried out for the future assessment years 2025, 2035 and 2050 to provide a basis for comparison to the reference year 2014. The focus of the planned assessments in the environmental dimension will concentrate on CO2, NOx and noise on the ground (measured in dB levels). As the focus on airport level affectslocal traffic distribution, the share of population affected by aircraft noise can additionally be estimated. If technically and methodologically feasible, the assessment at airport level will additionally cover SOx, H2O, VOC, particles  and local air quality to complete the environmental impact evaluation. For the socio-economic assessments the analysis at airport level will concentrate on mobility improvements expected for the assessment years 2025, 2045 and 2050 in comparison to the reference year 2014. Connectivity improvements, travel time savings and benefits for “remote” regions will be evaluated at airport level. Besides this airport-centered analysis, the socio-economic impact assessment at meso level is planned to also consider competitiveness assessments. These will focus on the benefits that are generated through the Clean Sky 2 programme. Due to the diversity of the topic, these assessments will be done in the form of status-quo analyses as the starting point for identifying future trends but with no particular linkage to the specific assessment years.

At "Air Transport System Level", Clean Sky 2 concept aircraft insertion into the global fleet is modelled to obtain worldwide fleet traffic forecasts and scenarios. Corresponding to mission and airport level, this will be done for the assessment years 2025, 2035 and 2050. The environmental impact analysis will in this respect cover CO2 and NOx emissions. Again, if technically and methodologically feasible, SOx, H2O, VOC and particles will be considered to estimate the global warming potential aggregated at world fleet level. The socio-economic impact analysis will be focused around the same assessment horizon and estimate the GDP and employment impact at national and global scale. In parallel to the competitiveness assessment foreseen for meso level, the plan is to have a corresponding assessment at the macro level by investigating the overall employment effects and looking at job creation in research and technological development relating to the Clean Sky 2 programme. To produce feasible results, this specific assessment will again concentrate on status-quo analyses at the point in time when it is conducted.

The technology assessment steps for the three different levels will be based on all concept aircraft considered in Clean Sky 2, including mainliners, regional aircraft, business jets, small air transport vehicles, fast rotorcraft, as well as on specific Technology Evaluator concept aircraft models. The latter provide the potential to integrate further Clean Sky 2 technologies. As these technologies are developed in the form of single components (e.g. a specific engine developed by an engine manufacturer) and not foreseen to be implemented in an aircraft model by the other Clean Sky 2 partners in form of a full demonstrator, this approach allows the Technology Evaluator to assess their impact in parallel to the three assessment dimensions.


Concept Models

In order to provide a holistic approach, the concept aircraft models of the Technology Evaluator are an integral part of the mission level assessments. They enable consideration of parts of the global fleet that are not under consideration, or going beyond the scope of Clean Sky 2 and by considering Clean Sky 2 technologies without being dedicated to one of the instruments’ separate concept models. As a first step, the mission level assessments for the Technology Evaluator concept models will be conducted to estimate the diverse environmental and socio-economic impacts at mission level. In the second step, the further mission level assessments will be conducted by the separate Clean Sky 2 partners themselves that will perform the aforementioned assessments of individual technologies at vehicle level and realise the synthesis of their own concept aircraft models. During the third step, these concept aircraft models will be delivered to the Technology Evaluator and checked for plausibility. Results of the Technology Evaluator concept aircraft mission level assessments will be combined with the results of the Clean Sky 2 partners’ own mission level assessments to complete the analysis.

Based on this step, airport and air transport system level assessments will be conducted with the Clean Sky 2 instruments and Technology Evaluator concept models as input. These will be integrated into the airport and air transport system level by using a fleet replacement approach that is combined with the outcome of traffic forecasts for the years 2025 and 2035 as well as in the form of scenarios covering the longer time horizon up to 2050. The forecasts and scenarios will in this respect consider the overall market demand development for the assessment years as well as the particular market perspectives for the different segments of aircraft considered within the Clean Sky 2 horizon (i.e. mainliners, regional aircraft, business jets, small air transport vehicles, fast rotorcraft). The objective is to deliver a harmonised set of forecasts and scenarios and to provide a realistic evaluation of the potential future development as a starting point for the holistic assessments of Clean Sky 2 technologies in respect of their environmental and socio-economic impact.



The Technology Evaluator contributes to the Clean Sky 2 programme with a consistent assessment framework to monitor and evaluate the technological progress in the aviation sector by focusing specifically on the benefits of Clean Sky 2. Concretely, this objective is realised within two assessment cycles. The first global assessment is scheduled for 2020 to estimate the progress that will have been reached during the first half of the programme’s lifetime. Its purpose is to provide further recommendations for the second half of Clean Sky 2 in respect of the overall programme goals. The second global assessment is set for the end of the programme in 2024 to assess the overall impact and to provide a final statement of the Clean Sky 2 benefits.

Besides these two milestones, the Technology Evaluator is a holistic assessment instrument and conceived in a way so that it can contribute to the continuous monitoring of technology developments. Therefore, it not only has a key role in the Clean Sky 2 landscape, but it also serves as a role model for general technology assessments in the field of aeronautical research.


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