Activity 4 - Analyse the Reference Scenario

Before the team starts the design of a new Airspace Concept, it is important to understand and analyse the existing operations in the airspace.  Analysis of current operations will enable the team to gauge how the airspace is performing today.  It allows the design team to know what works well in the airspace, and therefore should be kept, and what does not work well and could be improved; the aim of any airspace change is to safely improve efficiency, not to make a change for changes sake’.

The output of this analysis of current operations is commonly called the Reference Scenario.  The Reference Scenario includes all existing ATS Routes, SIDs/STARs, airspace volumes (e.g. TMA), ATC sectorisation, the air traffic data and as well as all the inter-centre and inter-unit coordination agreements. Description and analysis of the Reference Scenario is a crucial exercise – a step not to be missed.

Building this reference scenario will provide a benchmark against which the new Airspace Concept can be compared. Use of this benchmark makes it possible to measure the performance of the future planned Airspace Concept. It also becomes possible to establish whether the Safety and Performance criteria of the new Airspace Concept can be achieved.  It also provides a body of evidence for both the regulator and management that the proposed airspace change should be at least as safe as current operations if not safer and will deliver the efficiencies expected.

In some (rare) instances, the targeted Airspace Concept may be so different from the Reference Scenario that a comparison is not possible. This would be the case, for example, where a new airport is to be built with a new terminal airspace surrounding it. If, in such a case this new airport were intended to replace or complement existing operations at another terminal area, it could prove useful to compare the performance of the existing versus the new terminal area.