European CCO / CDO Action Plan

European CCO / CDO Action Plan


In 2020, a new Pan-European CCO / CDO Action Plan was adopted. The Action Plan includes new harmonised definitions, metrics and parameters to measure CCO and CDO operations in Europe, developed by the European CCO / CDO Task Force. The Action Plan introduces the Noise CDO (focusing on optimising that part of the arrival profile where noise is the primary environmental impact) and the Fuel CDO. The Fuel CDO measures the environmental performance of the entire arrival phase from top of descent, in terms of fuel burn / CO2[1].

The Action Plan also advocates a new harmonised metric for CCO / CDO performance measurement – “average time in level flight” - agreed by the Task Force taking into account current best practices from European stakeholders, and additional parameters for measurement urges all stakeholders to collaborate on optimising vertical flight efficiency and recommends a set of Key Principles that should be communicated on CCO / CDO.

The Action Plan introduces the new CCO / CDO performance dashboard, which details the CCO / CDO performance for all airports in Europe and all airlines that fly in Europe[2]. It enables Aircraft Operators to compare the CCO / CDO performance of their fleet across European airports and allows Airport Operators to measure the CCO / CDO performance of multiple aircraft operators at their Airports.

The Action Plan team has designed an ATCO refresher training on CCO / CDO and aircraft energy management, together with a sister CCO / CDO training course for Flight Crew, both available on the EUROCONTROL IANS Training Zone. These trainings, developed in collaboration with European ATCOs and Flight Crews, are aligned to provide guidance to optimise CCO / CDO from both the ATCO and Flight Crew perspectives, demonstrating the close collaboration between Flight Crew and ATCOs that is essential for enhanced vertical flight efficiency.

The European CCO / CDO Action Plan calls for a step change in the facilitation, promotion and implementation of optimised climb and descent profiles (CCO / CDO) so that the significant noise, fuel burn, emission and fuel cost savings generated by these techniques can be realised by Stakeholders. The Action Plan describes the latest technologies, procedures, harmonised performance measurement and stakeholder good practices for improved CCO / CDO facilitation, in order to enhance flight efficiency.

The Action Plan together with the CCO / CDO performance dashboard and a set of supporting resources detailed on the web pages of the European CCO / CDO Task Force constitute the CCO / CDO Tool Kit[3]. The objective of this Tool Kit is to provide information for stakeholders so that they can collaboratively implement more optimised climb and descent profiles and generate significant performance improvements for the climb and descent phases respectively.


In the Action Plan, Section 1 includes a set of Key Principles that the Task Force has identified to help stakeholders implement CCO and CDO and optimise climb and descent profiles.

Section 2 gives an introduction to CCO / CDO including background material on historical CCO / CDO work in Europe. It explains why the European CCO / CDO Task Force was created, gives key data on the potential environmental benefits available and describes the structure of the Action Plan.

Section 3 highlights the main outcomes of the European CCO / CDO Task Force whilst Section 4 includes the recommendations for both Shared and Individual responsibilities as a way of underpinning the key principles.

Appendix A describes a list of contributory factors that constrain the optimisation of the vertical flight efficiency of the climb and descent flight phases in European airspace. Each of these factors is explained in order to better understand how the complexity of each factor can limit optimised aircraft profiles together with the impact of the interaction of multiple factors.

Appendices B to Q detail a set of outcomes and actions that the European CCO / CDO Task Force has developed collaboratively to provide resources that can be used by aviation stakeholders to support CCO / CDO implementation and to optimise existing performance in the face of the constraints imposed by such contributory factors.

These outcomes and actions include potential solutions, good practices and case studies to address the contributory factors detailed in Appendix A which may impact the ability to fly CCO / CDO.

These Appendices are specifically designed so that the reader can go straight to the appropriate section of interest without having to trawl through the entire Action Plan.

These outcomes and actions include inter alia:

  • Harmonised definitions and metrics for measuring CCO / CDO performance;
  • The introduction of Europe-wide monthly CCO / CDO performance for all Airlines and Airports, on the CCO / CDO performance dashboard;
  • The creation of ATCO refresher training on aircraft energy management;
  • A proposal for a Computer-Based Training (CBT) and associated visual aids to support Aircraft Operator refresher training materials;
  • New proposals for ATCO and Flight Crew training objectives on CCO / CDO;
  • Enhanced guidance in airspace and procedure design to facilitate CCO and CDO;
  • A proposal for an airline CDO Policy together with supporting guidelines based on existing Aircraft Operator good practices; and
  • The sharing of good practices and case studies on CDO implementation, performance monitoring and collaboration.

Related articles

Further reading



  1. ^ SESAR analysis indicates that noise is the primary environmental impact below FL75 for arrivals
  2. ^ Subject to data availability
  3. ^ Available at:

SKYbrary Partners:

Safety knowledge contributed by: