Legal Aspects of Contingency

Legal Aspects of Contingency


Legal aspects of contingency deal with both International Civil Aviation Organisation (ICAO) and European Union (EU) Requirements and with the national interpretation of those obligations. They also relate to the liabilities under contingency and insurance that might be put in place to cover contingency operations.


Legal Obligations - ICAO and European Commission (EC)

The legal obligations for States and air navigation service providers (ANSPs) (as appropriate) to put in place contingency arrangements for air navigation services are enshrined in 2 legal instruments:

  • The Chicago Convention, Annex 11, Air Traffic Services, Chapter 2.29 (and Guidance Material to Chapter 2.29, Attachment C) which states, inter alia, “Air Traffic Services authorities shall develop and promulgate contingency plans for implementation in the event of disruption, or potential disruption, of air traffic services and related supporting services in the airspace for which they are responsible for the provision of such services”.
  • Commission Implementing Regulation (EU) No 2017/373 of 1 March 2017 laying down common requirements for providers of air traffic management/air navigation services and other air traffic management network functions and their oversight, Annex 3, Subpart A, ATM/ANS.OR.A.070 which states that “A service provider shall have in place contingency plans for all the services it provides in the case of events which result in significant degradation or interruption of its operations.”.

Moreover, in States where European legislation applies, and where the nature of the contingency measures is such that it requires the use of other ANSPs services or facilities, the ANSP needs to comply with Articles 10.1 and 10.2 of EC Regulation No 550/2004 which provides: “Air navigation service providers may avail themselves of the services of other service providers that have been certified in the Community. “Air navigation service providers shall formalise their working relationship by means of written agreements or equivalent legal arrangements, setting out the specific duties and functions assumed by each provider…”.


Most of the legal issues that arise under contingency take place when two different legal entities (i.e. two different States, two different ANSPs, civil and military ANSP) collaborate in contingency situations (contractual liability), or when execution of contingency measures has an impact on third parties (third party liability). This raises issues of liability.

Under Article 28 of the Chicago Convention; States are responsible for the (safe) provision of air navigation facilities and services in their airspace. Any failure to exercise fully and correctly this responsibility may incur the liability of the State.

Liability vis-à-vis third parties has to be distinguished from the contractual liabilities between the concerned parties in a service provision environment. The third parties' liability regime (i.e. actions by plaintiffs) is governed by national laws and sometimes public or private international law. The allocation of liability between the cooperating parties, as well as possible recourse actions, place of jurisdiction, dispute settlement procedures between the players (e.g. States, national supervisory authority (NSAs), and ANSPs) can be organised through agreements, contracts or regulatory acts. This is of particular importance in the context of contingency plans involving several ANSPs and/or cross-border cooperation. However, if written agreements can arrange the liability between the parties, they cannot arrange the right of actions of potential victims. Delegations of services or arrangements between ANSPs do not lift/remove the responsibilities and potential liabilities of the delegating ANSP (e.g. failing ANSP), which remains the one originally designated by the State in which airspace the service is provided. The liability of the air traffic controllers (ATCOs) involved in an accident when working under degraded or contingency modes would remain, but the level of the due diligence exercised would probably be assessed against the particular context and help mitigating the liability exposure. As a last remark, it should be outlined that the type of damage for which the liability of players can be invoked depends also from applicable national laws. National laws would help determine for instance whether economic damage suffered by airlines after the closing or restriction of airspace could be the subject of a claim.

Insurance Legal aspects of contingency also relate to insurance cover. In applying SES legislation, in particular Regulation 2017/373, ATM/ANS.OR.D.020 Liability and insurance cover, ANSPs are in principle covered against the risks resulting from their operations, mostly via insurance policies or State guarantees. This coverage should extend to the execution of contingency measures by the ANSP as an ‘aiding’ unit, and also if possible to support provided by other ANSPs to the ANSP as a ‘failing’ unit.

Cross Border Issues The cross-border provision of services under contingency raises further legal issues. In accordance with SES legislation, cooperation between ATS providers (and, where applicable, cooperation involving designated MET providers) requires written agreements subject to State approval. Applied to cross-border cooperation between foreign air traffic service providers (ATSPs), this principle requires the approval of the two States concerned. For other air navigation services Communication, Navigation, Surveillance and Aeronautical Information Services (CNS, AIS) this requirement does not exist in the Single European Sky (SES) legislation but both in view of the role attributed to States by the Chicago Convention and the potential impact on domestic ANS, it appears preferable that the State of the aiding ANSP be also at least informed (it should be noted that all ANSPs have to notify their (NSAs) of their agreements). Either the States arrange these issues between themselves and respectively delegate the detailed development of the plans to their ANSPs, or the ANSPs conclude a contingency plan/agreement between themselves that is submitted by each of them to their respective State for approval.

It would be useful that the States - or their NSA(s) - also agree on the mechanisms for coordination between them, for instance with regard to the common definition of requirements, the joint oversight by the Functional Airspace Blocks (FAB) NSA(s) and the approval of the contingency plans. Furthermore, as recommended by Annex 11 to the Chicago Convention, the States may have to ensure formal coordination with those neighbouring States which might be significantly affected in case of contingency. Any contingency plan developed by the ANSPs operating in the FAB should have to be a joint/coordinated plan, also agreed upon through a written agreement, and will need to be prepared before the start of operations of the FAB.

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