Thanks to an Occitan region funding, the OC’TAVIE project for “collaborative optimization of air transport relative to environment” (R&D project over 15 months) takes place in the problematic of reducing the environmental footprint of air transport at short, medium and long term.

Aircrafts produce carbonic gas and additional components qualified “not-C02” (as water steam, nitrogen oxide, sulfur oxide, hydrocarbons…) in atmosphere which participate to the global warming. In addition to the generation of gas and particles (C02 and not-C02), the creation of condensation trails taking the aspect of visible straight cloud following aircraft flight, increase the cloud covering. As this phenomenon could persist during hours, the condensation trails enforce the greenhouse effect. More recent evaluations demonstrate that this climatic fortification would be equivalent to the one induced by the C02 emission.

Nowadays only the C02 rejected by the aviation represent about 2 to 3 % of the global emission. The growth forecasts of air traffic for the 2015-2025 period by the ICAO (International Civil Aviation Organization) before the COVID-19 crisis were established at 4.1 % per year. Even if this growth is drastically slowed down at short term by the health context, the contribution of aviation to the climate change could become major. So, additional and accelerated efforts have to be employed in order to maintain the objectives of the Paris agreement about the climate.


With the motivation to preserve its activity, the aeronautical field shall propose solutions to contribute to the diminution of its impact on the environment. If numerous projects are initialized to elaborate new aircrafts, the results from the manufacturers should not be perceptible before the beginning of the next decade. Thus, the desired “green” effect of new aircrafts on the environment would be significant only after 2030 and beyond, when they will start to represent an important part of the global fleet. The need is to act before (at short and middle terms) without waiting innovation on aircraft and motorization.


In a complementary way with the management of airspaces, Improvements exist also but with limited and fragmented initiatives aiming to reduce the environmental impact of flights in adequation with the objectives of environmental performances in force in the airspaces (as the single European sky). It is necessary to find solutions and implement them now addressing the airspace managers and aircraft operators.


The OC’TAVIE project takes place in this perspective to propose theses new solutions involving the management of aircraft and airspaces, with a development strategy using short cycles in order to propose a reactive implementation at affordable cost.


OC’TAVIE project aims to:

  1. Propose assessment metrics for non-CO2 effects on the climate which are currently poorly controlled and which will have to be integrated into the final service. These metrics will have to be adapted to the needs of aviation and involved in the calculation of the global environmental impact of flights (not only CO2 effects). Thus, the project aims to acquire the ability to estimate more accurately the total impact (CO2 and non-CO2 effects) of flights on the atmosphere, in particular the one related to the phenomenon of condensation trails.

  2. Build the technical elements allowing the concept to be prototyped by relying on digital tools on board and on the ground as well as green procedures adapted and enriched by exchanges between pilots and controllers. This concept aims to offer a service allowing:

    • An airspace manager to declare a space-time for which he owns the ability to grant trajectory optimizations to flights adapted to the performance of the aircraft and favorable to the environment.

    • An aircraft operator to use this space-time to optimize the trajectory of his aircraft. This optimization can be done in an enforced way when the aircraft is equipped with a pilot terminal (tablet) simplifying the exchanges for optimization with the controllers. By combining the knowledge acquired on the C02 and non-C02 production of a flight with better collaboration between air traffic control and space users (air operators / pilots), it is therefore possible to take advantage of “Green Flag” declared airspaces. to reduce the environmental footprint of aviation.

  3. Test the Green Flag concept in a real environment. The real experiment aims to demonstrate the viability of the concept as well as its interest for the environment. This experiment involves the work of the various partners. It will also involve air operators. The experimentation will also provide a base for subsequent work via SESAR which will allow to work on the issues of deploying the solution in an international environment.

  4. Structure a French and Occitan partnership preparing the provision of 'connected cockpit' oriented services and enabling the environmental optimization of flight operations.

Partners, Co-funders


ONERA – research center: Expertise in research and development applied to aerospace. In particular, expertise about the environmental impact of aviation and the methods and algorithms for artificial intelligence required for decision tools used by aircraft companies and providers of management services for air traffic – ANSP.


CEFRACS – research center: Expertise in modeling and numerical simulation and high-performance computation, in particular in the aerodynamic and climate field.


DGAC/DSNA – Administration center: Expertise in the air traffic management. Expertise in development and prototyping of solutions for air traffic control, including all testing activities. Provide the resources needed such as the operational environment of training for air traffic controllers including test simulations and experimentations of new procedures identified in the Operational Concept.

ATMOSPHERE – PME: Expertise in satellite connectivity and these applications for aerospace.


CGX – PME: Expertise based on digital and disruptive approach in terms of publishing of aeronautical data and the integration of secure digital in real-time operation.


THALES Group (AVS/LAS) – GG (“Big Group”): Expertise in flight avionics, simulation and training: embedded equipment and functions for flight, the navigation and control of aircraft systems. Expertise in management system of air traffic (design, study, industrialization, operation…); expertise in digital solutions for ATM (Air Traffic Management) and methodology using agile development.


Air France – GG (« Big Group »): Operational expertise in end-to-end flights. Expertise in the management of multi carrier/multi-manufacture aircrafts. Expertise in flight execution.