Airspace

General principles

According with the provisions of the “Agreement on the establishment of the DANUBE Functional Airspace Block between Romania and the Republic of Bulgaria” (the DANUBE FAB State Agreement), the “DANUBE FAB airspace” comprise the airspace over the territory of Romania, the airspace over the territory of the Republic of Bulgaria and the airspace over those parts of the high seas where the Parties have accepted, pursuant to a regional agreement, the responsibility of providing air traffic services, referred to București Flight Information Region and Sofia Flight Information Region.

The airspace organisation is developed and harmonised in accordance with the Single European Sky legislation. The route network and the basic volumes of airspace were optimised in line with the European Route Network Improvement Plan (ERNIP) Part 1 in order to minimise coordination and to increase capacity for the same amount of workload.
General principles
DANUBE FAB Airspace
Design principles

Design principles

The main objective of the airspace design is to maximise the efficient use of airspace, whilst maintaining the level of safety applicable to air traffic operations within such airspace, with delineation free of national borders. In order to achieve this objective, the airspace design and structure will be based on common criteria as regards lateral and vertical delineation and designation. In the context of the DANUBE FAB Agreement, “DANUBE FAB airspace” consists of Bucharest FIR and Sofia FIR.

Both BULATSA and ROMATSA gradually implemented Free Route Airspace (FRA) within their individual airspace in November 2013 during night hours and on 30 March 2017, DANUBE FAB ANSPs, ROMATSA and BULATSA, together with HungaroControl (member of FAB Central Europe), introduced major changes in the airspace structure of the three States, by implementing South Eastern European Night Free Route Airspace (SEEN FRA) project.

In stepping forward towards the implementation of H24 Free Route Airspace (FRA) within DANUBE FAB, BULATSA and ROMATSA have commissioned EUROCONTROL to support this action with a prototype and full-scale real-time simulation validation (RTS), which was completed from October 27 until November 12, 2015 at the EUROCONTROL Experimental Centre in Bretigny/France.

The RTS simulated Free Route Airspace (FRA) across the whole DANUBE FAB airspace which involved a total of 18 sectors each operated by full sector teams (one executive and one planning controller). The simulation provided evidence that FRA can be expanded out of the current night-time FRA into H24 FRA on a seasonal basis (from winter, spring to summer) if controllers are supported with a set of advanced ATC tools.

Airspace configurations

The DANUBE FAB airspace structure became more flexible and adaptable, enhancing capacity, with a balance between the requirements of civil and military use.

Environmental requirements were taken into account in the process of redesigning the route network. Reconciliation of the different requirements is met through different airspace configurations. Each airspace configuration consists of different sectorisation adapted to the traffic structure and free route configuration was applied to a maximum extent.

Airspace configurations
Cross Border Provision of ANS

Cross Border Provision of ANS

The rationale of Cross Border Provision (CBS) of ANS was set out in the Article 20 of the DANUBE FAB Agreement. The intent of DANUBE FAB to implement CBS and further optimise the airspace boundaries of the States was clear throughout the development phase of the project.

Following the establishment of DANUBE Functional Airspace Block (DANUBE FAB) the two partner States of Romania and Bulgaria implemented two cross-border sectors on 11 December 2014, the first time that cross-border sectors have been implemented under a FAB framework.