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Mobility and Transport

Contingency "Clear the Sky" procedure between ANA Luxembourg and Belgocontrol

Findel, LuxembourgAdministration de la navigation aérienne (ANA), ANSP of Luxembourg

The Contingency "clear the sky" procedure was agreed on in 2013 between ANA Luxembourg and Belgocontrol in order to optimise Air Traffic Services in the event of a disruption to ANA LUX ATS units.

At the time, the loss of surveillance systems was not totally covered by the existing letters of agreement between ANA and Belgocontrol.

The scope of this cooperation is the establishment of an emergency procedure in case of a loss of surveillance/com system or in case of an evacuation of the OPS Room and standardization of procedure for all controllers. In case ANA is unable to provide ATS, Belgocontrol would assume control in Luxembourg TMA airspace above the Transition Altitude (4500 ft AMSL).

The major benefits are:

  1. Reduction of the risk of a mid-air collision and CFIT during the critical period.
  2. Standardization and predictability of ATCO actions.
  3. Better support from adjacent ATS providers during the critical period.

The letter of Agreement signed aims at defining the co-ordination working procedures that shall be applied between Brussels ACC and Luxembourg APP when providing ATS to General Air Traffic (IFR/VFR).

These procedures are supplementary to those specified in ICAO, EUROCONTROL and/or National documents.

Operational status: Both ATS units shall keep each other advised of any changes in the operational status of their facilities and navigational aids, which may affect the procedures specified in this Letter of Agreement.

This means that contingency measures are only executed in the event of a disruption of services, which may result in a complete, catastrophic outage of a specific ATS unit. In case of partial outage the relevant contingency measures are to be handled locally at each unit level. However, in order to improve the ATS capacity, it is not excluded that specific measures of this plan can be applied.

When the safe and orderly flow of air traffic in an area is seriously disturbed, harmonized measures shall be applied for contingency procedures.

In the context of the ICAO and EC obligations, the concept of contingency can be organized along a "Contingency Life-Cycle", composed of several phases:

  • 'Normal' operations
  • 'Emergency' situations, included in 'Degraded modes' of operations
  • 'Service Continuity'
  • 'Recovery' to normal operations
  • 'Back to 'Normal' operations

This high level Operational Concept is developed as a first attempt to provide the necessary framework and the appropriate methodology that should allow Belgocontrol to provide ATS within the Luxembourg TMA in case of disruption of ANA ATS provision. It should be included in a wider scope, that is, this document should be part of a global "Contingency Planning Strategy".

It is useful to put the "Contingency Planning concept" in the appropriate perspective. Contingency Planning of Air Navigation Services is defined at both ICAO and European Community levels. Furthermore, the roles and responsibilities of the States and the ANSPs may be different.

ANA is providing 2 annexes to this application form, on request the 3 others above mentionned OPS documents are also available for more details:

  1. ANA LUX Belgocontrol contingency handbook - Version 1.2
  2. BELGOCONTROL ANA LUXEMBOURG agreement on Service Continuity - Version 1.2
  3. Simulation report Contingency ANA LUX – Belgocontrol

Award criteria

Contribution to increasing safety of ATM systems, Contribution to reducing ATM costs, Potential to be replicated over the ATM network, Promoting partnerships, Contribution to change management


Contribution to increasing safety of ATM systems:

The provision of ATS by ANA APP is through radar-based services using a high-availability and fault-tolerant RDPS and ground-to-air communications system. Moreover, the approach function is conducted from a bespoke building designed to minimize the risk from fire or other potentially catastrophic hazards. Notwithstanding that the technical equipment and infrastructure are designed to ensure that total loss of surveillance and/or imminent evacuation should occur extremely rarely, additional safety management considerations dictate that an appropriate procedure is in place to further reduce the possibility of accidents during the critical time between the occurrence of a catastrophic failure and/or imminent evacuation and the point at which a safe environment with no aircraft can be achieved. The "Clear the Sky" procedure is designed to minimize, as far as practical, the risk of mid-air collisions and/or CFIT during this period. The procedure is considered as safe because it meets the following criteria: a. The procedure has been designed and developed in accordance with the objectives of the EUROCONTROL SAM Procedure Assurance Level 4. b. The procedure was implemented and maintained in accordance with the objectives of the EUROCONTROL SAM Procedure Assurance Level 4. c. The end state of the procedure, a "clear sky" without IFR aircraft is safe. d. The procedure is designed to minimize the risk to aircraft during the critical period between a catastrophic technical failure and/or imminent evacuation and the end state of a clear sky. e. Any negative impacts of the procedure on the ability of the ATCO team to manage the critical situation have been reduced as far as practical.

Contribution to reducing ATM costs:

The cooperation with Belgocontrol has permitted ANA to save the cost of new contingency infrastructure and equipment dedicated to ATC APP contingency. The cost of fall-back training for Luxembourg ATCOs was also reduced.

  • Potential to be replicated over the ATM network: If Single European Sky is extended to TMA level, Europe presents a lot of potential for this kind of cross-border cooperation for contingency procedures. E.g.: triangle France-Switzerland-Germany with overlapping TMA's, Benelux TMA's.
  • Promoting partnerships: This cooperation develops synergies in cooperation with FABEC partners in all service areas
  • Airspace optimization and or delegation in collaboration with FABEC partners: Increase safety, cost-efficiency, capacity and reduce environmental footprint.
  • Establish common contingency solutions: Reduce infrastructure investment / maintenance costs (no need for ANA to invest in an extra location to assure contingency Approach).
  • Radar data exchange and coverage improvement: Cost efficient service provision, training, project management through optimized use of available resources.
  • Share / use available competence with FABEC partners and training.

In this respect, ANA, like its partners forming the FABEC (Functional Airspace Block Europe Central), will meet the security objectives, environmental aspects and economic efficiency. Belgocontrol provides air traffic control over the Grand Duchy of Luxembourg between flight levels 145/165 and 245, above which the Maastricht control center operated by Eurocontrol (MUAC) is competent. ATC APP and TWR from the airport of Luxembourg (ELLX) is currently provided by ANA Lux. Collaborative projects between Belgocontrol and ANA Lux are supported by an agreement-cadre1. In addition, costs for air traffic control inherent in Lux ANA operations, Belgocontrol and Eurocontrol in Belgium and the Grand Duchy of Luxembourg are integrated into a consolidated Belgo-Luxembourgish basis cost that determines the definition a common unit rate for both countries. Therefore, cost reduction of a party has a direct impact on all users of the Belgian and Luxembourg airspace. On the Belgian side, the federal government has stipulated in its coalition agreement, the objective (for Belgocontrol) for the integration of service delivery and airspace in the Benelux as a springboard towards achieving the FABEC and SES (Single European Sky). Furthermore, Article 18 of the third Belgocontrol management contract (with the Belgian State) states that "Belgocontrol aims to achieve effective collaboration with ANA in the financial, operational and technical side. DFS was involved in both test and ATCO training.

Contribution to change management:

The main change to manage in SES will be to move from a sectorized individual ATM provision to cross border sectoring with flexible service provision. Delegating contingency procedure from one nation's TMA sector to another nation's sectors by combining even different ATM systems is at the heart of change management for the Single European Sky.

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