Flexible Use of Airspace

Flexible Use of Airspace The objective of the Concept of Flexible Use of Airspace (the FUA Concept) is to increase ATM system capacities and reduce traffic delays, i.e. to shorten flight paths and thus reduce costs as well as emission of harmful gases into the environment. This objective is achieved by maximum common use of the available airpace in a safe way by civil and military users.

Basic characteristics of the FUA Concept:
  • Airspace is one continuum,
  • Any allocation of airspace for exclusive use by a particular user shall be temporary and based on real-time requirements within a specific time period,
  • Contiguous airspace structures are designed by operational requirements and not by national boundaries.
The FUA Concept is developed at three interdependent levels.

At Strategic Level 1 the national airspace policy is established , airspace structures and procedures for their daily allocation to user requirements are designed. The tasks at Level 1 are performed by the National Commission for Airspace Management, and supported by Croatia Control as the ANS provider, together with other stakeholders.

At Pre-tactical Level 2 daily allocation of flexible airspace structures (CDR - conditional route, TRA- temporary reserved airspace, TSA-temporary segregated area, CBA-cross border area) to user requirements is performed, and relevant information is promulgated to airspace users in the Airspace Use Plan (AUP) and Updated Use Plan (UUP), or in any other way appropriate to air traffic, depending on the degree of airspace segregation. The tasks at Level 2 are performed by an Airspace Management Cell. By the time the AMC is established, these tasks within the required scope are performed by the shift supervisor at the Zagreb ACC.

Tactical Level 3 covers real-time use of airspace, allowing safe Operational Air Traffic (OAT) and General Air Traffic (GAT) operations. This task is performed by the Zagreb ACC.

AMC portal is used for reservations of airspace structures, promulgation of information about airspace reservations and for communication with airspace users.