Why aircraft-specific data enhances assurance and completeness

A verifier’s view

By Alexander Stathakis, ACA Level 5 Verifier.

Accurate, verifiable data is the foundation of credible airport carbon reporting. Having verified airport carbon footprints for more than twelve years under the Airport Carbon Accreditation programme (ACA) across Australia and New Zealand, I have seen the evolution of how airports manage and report their emissions. Most have mastered the fundamentals of Scope 1 and 2 accounting, such as fuel use, electricity, and refrigerants, but the real challenge has been moving into Scope 3.

Scope 3 emissions capture activities that extend beyond the airport’s operational boundary. These include aircraft operations, passenger surface access, freight, and outsourced services. For airports, these emissions typically represent more than 90 per cent of their total carbon footprint, yet they are the hardest to accurately measure. As an ACA verifier, I am responsible for independently assessing the completeness and accuracy of airport greenhouse gas inventories. I have reviewed countless data sets from airports of all sizes, and the data is typically scattered across different departments and stakeholders: fuel suppliers, finance teams, and air navigation service providers. Reconciling this information into a coherent emissions inventory is time-consuming and resource-intensive, but it is essential for a complete and credible assessment.

Why detail matters

In the higher ACA accreditation levels, the expectation shifts from estimation to influence. Although aircraft movements dominate the emissions profile of most airports, many reporting systems rely on overly simplified assumptions, such as average aircraft categories, default emission factors, and generic flight distances, which are sufficient for basic reporting but fall short at higher grades.

Detail really matters. For example, knowing that “a 737 flew the route” is helpful, but not enough. The actual aircraft might be an older variant with a different engine type or a newer model fitted with winglets that reduce fuel burn. These differences matter when an airport is designing incentive programs, engaging with airlines, and planning infrastructure. Knowing which exact aircraft is using its facilities allows the airport to plan with far greater confidence. Gate power demand, ground power unit sizing, hydrogen refuelling potential, sustainable aviation fuel blending volumes, and even apron layouts can all be better planned with the knowledge of the mix of aircraft operating.

The granularity provided by aircraft-level detail transforms emissions data from a reporting obligation into a planning and investment tool. Without that visibility, airports risk committing capital to assets that are either underutilised or technologically mismatched to the fleets they aim to serve.

Independent 3rd party data

Airports are increasingly using independent aviation data, working directly from flight radar and satellite feeds to determine every aircraft movement by its tail number. This enables them to determine detailed configuration characteristics such as engine type, number of seats, winglets and sharklets. The result is a far more accurate and granular picture of what is flying in and out of the airport than what schedules or standard fleet data might suggest.

Beyond the obvious accuracy benefits, two key factors are driving airports in this direction:

• Credibility – data is based on recognised methodologies that can be independently verified under ACA and other assurance frameworks
• Actionability – aircraft-specific insights support infrastructure planning, operational efficiency, and airline engagement strategies aligned with decarbonisation goals

This independent data capability brings a higher level of assurance to airport emissions reporting. It strengthens the link between reported data and operational decision-making, supporting the progression from compliance to leadership.

From measurement to leadership

The progression from ACA Level 1 to Level 5 reflects a broad shift from measurement to leadership in sustainability strategy. Data quality becomes the foundation for influence, enabling airports not only to meet accreditation requirements but also to shape the decarbonisation of aviation itself. At Levels 3, 4 and 5, airports must demonstrate effective decarbonisation planning and stakeholder engagement, underpinned by robust, traceable data. When airports can show the performance characteristics of the exact aircraft operating from their facilities, data-driven discussions with airlines, regulators, and financiers become more strategic.

In summary, aircraft-specific information is not just a technical enhancement to emissions accounting but represents a new level of clarity and credibility. In turn, this enables airports to link their reporting more directly to investment, engagement, and long-term decarbonisation outcomes.

About the Author:

Alexander Stathakis is Managing Director of Conversio Pty Ltd, an experienced ACA Verifier in the aviation sector working with more than 25 airports across the Asia-Pacific region over the past 12 years. Specialising in greenhouse gas measurement, reporting, and verification, Alex helps airports to translate complex emissions data into actionable decarbonisation strategies required by the higher levels of the ACA programme.