CarbonPass app methodology

Emissions data for flight routes

Operator  Route: Jersey to…  Aircraft  Emissions for single economy journey for one person (kg CO2e) 
British Airways  Heathrow  Airbus A319 & A320  56.6 
Easyjet  Glasgow  Airbus A319 & A320  96.1 
  Gatwick  Airbus A319 & A320  49.8 
  Liverpool  Airbus A319 & A320  68.6 
  Luton  Airbus A319 & A320  54.8 
  Manchester  Airbus A319 & A320  62.9 
Blue Islands  Birmingham  ATR 42-320 & ATR 72-500  40.0 
  Bristol  ATR 42-320 & ATR 72-500  27.6 
  East Midlands  ATR 42-320 & ATR 72-500  42.4 
  Exeter  ATR 42-320 & ATR 72-500  22.5 
  Guernsey  ATR 42-320 & ATR 72-500  8.2 
  Southampton  ATR 42-320 & ATR 72-500  23.7 

Methodology used for these calculations

The ICAO Carbon Emission Calculator requires that the user input the airports of origin and destination for a direct through flight. This is then compared with the published scheduled flights to obtain the aircraft types used to serve the two airports concerned and the number of departures per aircraft. Each aircraft is then mapped into one of the 312 equivalent aircraft types in order to calculate the fuel consumption for the trip based on the great circle distance between the airports involved in the journey.

The passenger load factors, and passenger to cargo ratios, obtained from traffic and operational data collected by ICAO, are then applied to obtain the proportion of total fuel used which can be attributed to the passengers carried. The system then calculates the average fuel consumption for the journey weighted by the frequency of departure of each equivalent aircraft type. This is then divided by the total number of economy class equivalent passengers, giving an average fuel burn per economy class passenger. The result is then multiplied by 3.16 (constant representing the number of tonnes of CO2 produced by burning a tonne of aviation fuel) in order to obtain the amount of CO2 footprint attributed to each passenger travelling between those two airports. 

The full methodology can be seen here, and data is updated annually by ICAO: 

https://www.icao.int/environmental-protection/CarbonOffset/Documents/Methodology%20ICAO%20Carbon%20Calculator_v11-2018.pdf