Engine emissions
Engine emissions play a key role in aviation’s environmental footprint. They are produced when fuel is burned in aircraft and helicopter engines and affect both air quality and the climate. New measurement and calculation methods now make it possible to record and assess emissions more accurately.
Large aircraft engines (large turbojet and turbofan engines) are responsible for the majority of aircraft emissions and are subject to internationally harmonised certification requirements with globally applicable International Civil Aviation Organization (ICAO) limits. The relevant emissions data is publicly available in the ICAO Aircraft Emissions Databank (more information below). Most categories of aircraft in use worldwide have small engines that produce low emissions. As they are not subject to ICAO certification standards, there are no certification data available for these engines. As part of its statutory mandate, the FOCA also tests the emissions of these engines and makes the relevant data available. ICAO Doc 9889 includes instructions on calculating emissions around airports.
Piston engines
The FOCA has developed a measurement and calculation method for determining emissions from aircraft piston engines, in order to further improve emissions inventories. Measurement results and emission data sheets for the most widely used aircraft piston engines are provided here. The list of engines is gradually being expanded.
In addition to its information on methodology, the documentation also highlights operational aspects and their impact on emissions, as well as opportunities for reducing emissions.
Summary report, appendices and data sheets
Helicopter engines
Individual emission data for helicopter engines have been largely unavailable to the public thus far. The FOCA has therefore developed its own calculation method in order to determine helicopter emissions with greater accuracy. The method is based on a principle of scaling emissions based on engine power and running time.
Guide to estimating helicopter emissions
Categorised small business turbojet, turboprop and helicopter engines
Individual emission data for small business turbojet engines (less than 26.7kN thrust) and turboprop engines have thus far been largely unavailable to the public. The FOCA provides a database with categorised emission data for these engines, as well as for helicopter engines. An additional spreadsheet contains suggested phase times for estimating emissions during the landing and take-off cycle. The data complies with the latest version of ICAO Doc 9889 and is gradually being supplemented by some of our own measurements.
Large turbojet and turbofan engines
Emission factors and fuel consumption from the emission certification of turbojet and turbofan engines are collected in the ICAO emissions database. It contains an overview of all engines for which manufacturers have provided data, as well as data sheets for each individual engine. The database is publicly available at: