Defining Short, Medium, and Long-Haul Flights for Air Transport

In carbon accounting, categorizing flights by distance is crucial for accurately estimating their carbon emissions. Here’s how flight categories are typically defined according to common publishing authorities:

US EPA Definitions

The US Environmental Protection Agency (EPA) generally defines flights with different ranges that may vary based on carbon inventory guidance:

• Short-Haul Flights: Typically under 300 miles (approx. 482 kilometers)
• Medium-Haul Flights: Between 300 and 2,300 miles (approx. 482 to 3,701 kilometers)
• Long-Haul Flights: Over 2,300 miles (approx. 3,701 kilometers)

DEFRA Flight Distance Categories for Carbon Accounting

The UK Department for Environment, Food & Rural Affairs (DEFRA) categorizes flights for carbon accounting into the following groups:

• Domestic, to/from UK: Flights within the United Kingdom.
• Short-Haul, to/from UK: Flights to and from the UK with distances up to 3,700 kilometers.
• Long-Haul, to/from UK: Flights to and from the UK with distances over 3,700 kilometers.
• International, to/from non-UK: Flights that are international but not directly to or from the UK.

Why These Categories Matter

Defining flight categories by distance allows carbon accounting tools to more accurately calculate emissions. These categories are crucial because emissions per kilometer vary significantly by flight distance due to differences in fuel burn patterns. Shorter flights tend to have higher emissions per kilometer, as a larger proportion of fuel is consumed during the high-energy takeoff and landing phases. In contrast, long-haul flights, though higher in total emissions, are more fuel-efficient per kilometer flown due to the extended cruising period, where fuel burn is lower. By categorizing flights this way, DEFRA enables organizations to apply emission factors that more accurately reflect the science of fuel consumption patterns, leading to a more precise carbon footprint assessment.