Flight: ICAO

💡 High-Level Description:

The International Civil Aviation Organization (ICAO) plays a pivotal role in guiding aviation-related environmental policies on a global scale. Recognizing the aviation industry's significant carbon footprint, ICAO has developed methodologies specifically tailored to the flight passenger sector, aimed at determining its environmental impact. The overarching goal is to facilitate a harmonized global approach to address greenhouse gas emissions from aviation.

ICAO's carbon calculation methodology incorporates several variables, including aircraft type, flight distance, fuel burn rates, and passenger load factors. These metrics are then standardized across all member states, providing a cohesive measurement standard. By implementing such comprehensive strategies, ICAO not only helps industries to identify areas of improvement but also sets the foundation for global initiatives such as the Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA), targeting a carbon-neutral growth for international aviation from 2020.

The ICAO methodology does not include the ICEC dataset.

API Request

{
    "expand": [
        "items"
    ],
    "items": [
        {
            "type": "flight",
            "methodology": "ICAO",
            "external_reference": "test_7",
            "origin": "BER",
            "destination": "JFK",
            "aircraft_type": "737",
            "number_of_travelers": 1,
            "booking_class": "business",
            "airline": "AA",
            "fare_class": "Y"
        }
    ]
}

• Default Values

  • "booking_class": "economy"

  • "aircraft_type": "320"

Calculation Specifics

CO2 per pax = 3.16 * (total fuel * pax-to-freight factor) / (number of Y-seats * pax load factor)

• Total fuel: The weighted average of the fuel used by all flights departing from the origin airport to reach the destination airport. The weighting factor is the ratio of the number of departures for each equivalent aircraft type to the total number of departures.

• Pax-to-freight factor: The ratio calculated from the ICAO statistical database based on the number of passengers and the tonnage of mail and freight transported in a given route group.

• Number of Y-seats: The total number of economy-equivalent seats available on all flights serving the given city pair.

• Pax load factor: The ratio calculated from the ICAO statistical database based on the number of passengers transported and the number of seats available in a given route group.

3.16 is a constant representing the tonnes of CO2 produced by burning one tonne of aviation fuel.

The methodology uses the Great Circle Distance (GCD) between airports as input to calculate the fuel used, and thus estimate CO2 emissions. GCD is by definition the shortest distance between two points on the surface of a sphere. This distance can be calculated by using the geographical coordinates of the two points concerned. The coordinates for the airports involved are obtained from the ICAO Location Indicators database (ICAO Doc 7910). Once the GCD is calculated, it is then corrected by a factor depending on the distance between the two airports concerned. The correction factor is needed in order to include the emissions of distance flown in excess of the GCD, stacking, traffic and weather-driven corrections. According to EIG, the actual distance flown compared with GCD that is given in the scheduled flights timetable may vary up to 11% in Europe (ANCAT/EC2 1998).

GCD	Correction to GCD
Less than 550 Km	+ 50 Km
Between 550 Km and 5500 Km	+ 100 Km
Over 5500 Km	+ 125 Km

API Request Items

• "type": "flight" (required)

• "methodology": "ICAO" (required)

• "external_reference": A unique identifier that helps you link the resulting emissions to the requested item. Especially useful if multiple items are requested since SQUAKE cannot guarantee to keep the same order. The maximum length is 128 characters.

• "number_of_travelers": Minimum value is 1. The default value is 1.

• "origin": SQUAKE will try to resolve the origin/destination regardless of its format. Ideally, for addresses use the Post standard, for airports use IATA/ICAO code (format: ^[A-Z]{3,4}$, e.g. "MUC"), for other locations used in trade and transportation use UN/LOCODE codes (format: ^[A-Z]{2}\W?[A-Z2-9]{3}$, e.g. "DEHAM"). You can also pass lat/long (format: ^[-+]?\d{1,3}\.\d{1,10}\s?,\s?[-+]?\d{1,3}\.\d{1,10}$, e.g. "+40.712,-74.006").

• "destination": SQUAKE will try to resolve the origin/destination regardless of its format. Ideally, for addresses use the Post standard, for airports use IATA/ICAO code (format: ^[A-Z]{3,4}$, e.g. "MUC"), for other locations used in trade and transportation use UN/LOCODE codes (format: ^[A-Z]{2}\W?[A-Z2-9]{3}$, e.g. "DEHAM"). You can also pass lat/long (format: ^[-+]?\d{1,3}\.\d{1,10}\s?,\s?[-+]?\d{1,3}\.\d{1,10}$, e.g. "+40.712,-74.006").

• "booking_class": If you don't pass a booking_class, then fare_class and airline are highly recommended. SQUAKE will then automatically resolve the correct booking_class. For ICAO, economy is the default.

• "distance_in_km": Prioritized over origin and destination. If you don't have a distance_in_km, you can use origin and destination and the distance will be automatically resolved. If you pass both distance_in_km and origin/destination, then distance_in_km will be used.

• "aircraft_type": Aircraft type in the IATA or ICAO format.

• "fare_class": The combination of fare_class and airline is mutually exclusive with booking_class. This is a single letter, e.g., Y, J, etc.

• "airline": The IATA Designator of an airline, e.g., LH. Airline names are also supported, SQUAKE will then automatically resolve it. The combination of fare_class and airline is mutually exclusive with booking_class.

• "sustainable_fuels": Indicates the usage of sustainable fuels. This lowers the computed emissions in SQUAKE but is not part of the current official emissions frameworks.

• "carbon_reduction_percentage_of_total": The percentage of emissions reduction through the usage of sustainable fuel. The minimum value is 0, and the maximum value is 1. Default value is 0.

Sample API Response

{
    "carbon_quantity": 454070,
    "carbon_unit": "gram",
    "items": [
        {
            "carbon_quantity": 454070,
            "carbon_unit": "gram",
            "external_reference": "test_7",
            "type": "flight",
            "methodology": "ICAO",
            "distance": 6522.0,
            "distance_unit": "kilometer"
        }
    ]
}

Bibliography

• ICAO Carbon Emissions Calculator Methodology Version 13.1 (2024, Aug). ICAO. Retrieved from https://applications.icao.int/icec/Methodology ICAO Carbon Emissions Calculator_v13_Final.pdf