European consortium launches ZENITIA to chart the climate-neutral future of flight

Aviation stands at one of the most consequential crossroads in its history. By 2050, European air traffic is projected to grow by more than 50 percent compared with 2023 levels, yet the continent has simultaneously committed to a climate-neutral future under the European Green Deal. Reconciling those two trajectories, more planes in the sky and a radical reduction in aviation’s climate footprint, is not simply a matter of building new engines. It requires a fundamental rethinking of how next-generation aircraft, sustainable fuels, airports, and air traffic management systems will interact as an integrated whole. That is the ambition behind ZENITIA, a new European research project coordinated by Universidad Carlos III de Madrid (UC3M), which has just held its kick-off meeting and will run for 30 months within the framework of the SESAR 3 Joint Undertaking under the European Union’s Horizon Europe research and innovation program.

ZENITIA, whose full name is Zero-Emission Next-Gen Innovation and Technology Integration for Aviation, brings together nine organizations from academia, industry, and air traffic management across Europe and beyond. The consortium includes UC3M in Spain, Boeing Aerospace Spain and Boeing Deutschland GmbH, Estuaire SAS in France, Future Needs Management Consulting Ltd. in Cyprus, Imperial College London and the University of Cambridge in the United Kingdom, the International Federation of Air Traffic Controllers’ Associations (IFATCA) in Canada, and Technische Universiteit Delft in the Netherlands. This mix is deliberate: the project’s premise is that climate science, aircraft engineering, operational simulation, and the practical realities of air traffic control must be developed in conversation with one another rather than in separate silos, if the aviation sector is to make evidence-based decisions about its transition.

Abolfazl Simorgh, project coordinator and professor in UC3M’s Aerospace Engineering Department, frames the challenge in stark terms. According to Simorgh, ZENITIA addresses a central question for future aviation: how to ensure that next-generation aircraft and fuels deliver measurable climate benefits while remaining safe, efficient, and manageable across airports and airspace. His stated approach is to connect environmental science with gate-to-gate operations and AI-enabled scenario analysis, turning today’s uncertainty into evidence that stakeholders can actually use. That framing matters because the current debate around zero-emission aviation is often dominated by promises and prototypes, while the operational and atmospheric consequences of introducing radically different aircraft into a mixed fleet remain poorly quantified.

The scientific gaps the project targets are specific and, until now, persistent. Researchers still lack detailed characterizations of both evolutionary and revolutionary aircraft concepts, including their payload and range limitations, their expected flight profiles, and their wake behavior, the turbulent air patterns that trail behind aircraft and constrain how closely and safely they can follow one another. Equally underexplored are the climate effects of non-CO₂ emissions, such as nitrogen oxides, water vapor, and contrails, which are believed to contribute significantly to aviation’s total radiative forcing, and the operational implications of airports and airspaces handling mixed fleets in which conventional kerosene-burning jets coexist with hydrogen-powered or battery-electric designs. Without this knowledge, regulators and infrastructure planners risk making expensive decisions on incomplete evidence.

To close these gaps, ZENITIA will develop three integrated solutions designed to transform climate science into practical operational tools. The first is high-fidelity environmental impact modelling, which will combine aircraft design and dynamic performance simulation with emissions estimation and atmospheric science. Crucially, the modelling will capture both CO₂ and non-CO₂ effects, including contrails, nitrogen oxides, and water vapor, alongside local air quality around airports. The models will be validated against real-world observations and consolidated industry data, a step intended to give the resulting estimates the credibility required for regulatory and investment decisions rather than leaving them as purely theoretical exercises.

The second solution is a gate-to-gate mixed-fleet simulation capability. Rather than examining aircraft in isolation, these simulation tools will model and optimize complete flight operations in which conventional and zero-emission aircraft coexist, from the departure gate through taxi, takeoff, cruise, descent, and arrival at the destination gate. The tools will assess airport infrastructure needs and identify operational best practices, responding directly to priorities set by major European initiatives such as the Alliance for Zero Emission Aviation (AZEA) and SESAR, the EU’s flagship air traffic management research program. This operational lens is essential because a hydrogen aircraft, for example, is not merely a different powerplant in the air; it implies different refueling procedures, storage requirements, turnaround times, and safety protocols on the ground.

The third pillar is an interactive decision-support platform covering the critical transition window from 2035 to 2050. The platform will offer a dashboard through which users can simulate aviation scenarios for 2035, 2040, and 2050, centralizing environmental, operational, and infrastructure data in a single interface. The intended audience is deliberately broad: regulators, airlines, and policymakers will be able to explore how different fleet compositions, fuel adoption rates, and infrastructure investments interact, and to plan regulations and capital expenditure that align with the EU Green Deal. In effect, the platform aims to function as a flight simulator for policy, allowing decision-makers to test the consequences of their choices decades before those choices become irreversible.

Industry participation gives the project an important grounding in real-world data. Eduardo Carrillo de Albornoz, Managing Director of Boeing Global Technology-Europe, emphasized the industrial contribution, noting that Boeing Aerospace Spain’s Global Technology division will provide OEM performance data to evaluate the fidelity of the models developed for kerosene-powered aircraft. He added that, together with UC3M and the consortium partners, Boeing looks forward to moving the dial on next-generation aircraft technology. This benchmarking role is more than a formality: any model that claims to predict the climate and operational behavior of future zero-emission aircraft must first demonstrate that it can accurately reproduce the known performance of today’s fleet, and access to manufacturer performance data is what makes that validation possible.

The project’s methodological backbone is computational simulation and modelling, an approach that reflects both the scale of the problem and the impossibility of testing future aviation systems experimentally. Researchers cannot fly a hypothetical 2045 fleet to measure its contrail formation or its effect on airport throughput. Instead, they must build physics-based and data-driven models, couple them across disciplines from combustion chemistry to air traffic flow management, and interrogate them with artificial intelligence to explore vast scenario spaces. The involvement of IFATCA ensures that the human dimension, the air traffic controllers who will one day sequence hydrogen aircraft alongside conventional jets in increasingly crowded skies, is represented from the outset rather than retrofitted at the end.

What makes ZENITIA notable in the broader landscape of European decarbonization research is its insistence on integration. Many projects have attacked individual pieces of the puzzle, cleaner fuels, novel airframes, contrail avoidance, or airport electrification, but the transition to climate-neutral aviation will succeed or fail as a systems problem. A fleet that reduces CO₂ but increases contrail warming, or an aircraft that is efficient in cruise but disruptive on the ground, could undermine the very climate targets it is meant to serve. By building validated environmental models, mixed-fleet operational simulations, and a forward-looking decision platform within a single 30-month effort, the consortium aims to give Europe a coherent evidence base for one of the most complex technological transitions in modern transport, and to do so while the window for meaningful 2050 action remains open.

Subject of Research: Integrated modelling and simulation of next-generation aircraft, sustainable fuels, and mixed-fleet operations for climate-neutral European aviation

Article Title: UC3M coordinates the European project ZENITIA to accelerate climate-neutral aviation

Article References: UC3M coordinates the European project ZENITIA to accelerate climate-neutral aviation. (n.d.). Original publication

Image Credits: AI Generated

DOI: Not provided

Keywords: ZENITIA, climate-neutral aviation, UC3M, Horizon Europe, SESAR 3 Joint Undertaking, zero-emission aircraft, sustainable aviation fuels, non-CO2 emissions, contrails, mixed-fleet simulation, air traffic management, decision-support platform