Description:

The CAEP Modelling and Databases Group (MDG) synthesizes the input provided from the technical working groups. Typical analyses include the projection of future environmental trends, the evaluation of stringency options for environmental Standards, and environmental benefits associated with proposed measures. The MDG’s work is carried out using the most sophisticated aviation models for local air quality, noise, and greenhouse gas emissions, as well as related databases available worldwide.

Current work:

The MDG work programme for the CAEP/14 cycle (2025-2028) includes various topics such as:

• Environmental trends projection: conduct an updated trends projection for noise, NOx, PM, fuel burn, and CO2.
• Existing model and database management: maintain version control of models and databases used in support of specific CAEP analyses.
• Maintenance of ICAO Doc 9911: update the Doc 9911 (Recommended Method for Computing Noise Contours Around Airports) and support for other relevant ICAO documents, as requested through coordination with other CAEP working groups.
• COD improvements: Develop and maintain the Common Operations Database (COD) and manage the acquisition and treatment of additional State data.
• NOx Stringency Analysis: conduct a NOx Stringency Analysis with other CAEP working groups, adhering to the outcome being more stringent regulatory levels of aircraft engine NOx emissions.

• Evaluation process of the new models and tools.

   

Main publications (Reference publications):

• 42^nd Sessions of ICAO Assembly – Working Paper: Consolidated statement of continuing ICAO policies and practices related to environmental protection (General Provisions, Noise and Local Air Quality).
• Doc 9889 – Airport Air Quality Manual.

• Doc 9911 – Recommended Method for Computing Noise Contours Around Airports.

   

Additional references:

• Article: Environmental Trends in Aviation to 2070. ICAO Environmental Report 2025.
• Article: Noise Monitoring Systems Good Practices. ICAO Environmental Report 2025.
• Article: Standards and Advances in Airport Air Quality Modelling. ICAO Environmental Report 2025
• Article: ICAO’s work on NOx emissions regulation. ICAO Environmental Report 2025.
• Website: ICAO Environmental Trends
• Website: ICAO Models and Databases
• Website: ICAO Aircraft Noise

• Website: ICAO Local Air Quality