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Reducing the risk of naval incidents

Reducing the risk of naval incidents
Photo from Kiel, Germany, during the 2019 Baltic Operations (BALTOPS) exercise. Photo: US Navy.

This month, 18 countries are participating in a North Atlantic Treaty Organization (NATO) naval exercise in the Baltic Sea. The Baltic Operations (BALTOPS) exercise is noteworthy because it will be led by the 2nd Fleet of the United States Navy, which was disbanded in 2011 but reconstituted in 2018 with a wide area of operations from the east coast of the USA to the Barents Sea. The exercise will be an opportunity to test the NATO Command for the Atlantic that was created in 2018.

Changes in military plans have increased the likelihood that armed forces will operate in proximity in Europe, including navies. Navies now maintain a forward presence in the Baltic Sea and in the Black Sea to demonstrate commitment to allies, prepare for crisis response and strengthen deterrence. As explored in the new SIPRI Policy Paper ‘Reducing military risk in Europe’, military exercises are increasingly likely to simulate combat scenarios. Navies sometimes conduct freedom of navigation missions (FONOPS) to challenge what are seen as excessive maritime claims by moving ships into or through what coastal states consider restricted waterways, where the presence of warships requires consent or where intelligence, surveillance and reconnaissance activities will be contested.

Ships and aircraft from states that are not participating in such exercises will monitor them closely, and Russian aircraft and warships are expected to be present in the sea space where BALTOPS takes place. These different naval deployments all create the scope for incidents that could escalate into more serious confrontation.

The states that participate in the Organization for Security and Co-operation in Europe (OSCE) have discussed proposals to update the Vienna Document on Confidence- and Security-Building Measures (CSBMs) for two decades, but with little substantive progress. Moreover, the strategic geography of Europe at the end of the 1980s (when the current CSBM regime was largely defined) promoted a continental perspective from which naval measures were largely absent. A limited CSBM regime was created in the Black Sea, but it is facing major challenges. As naval activities are increasing in scale, multiplying in quantity and being contested in the Black Sea, this regime may already be redundant.

The main objective of the CSBM framework is to promote cooperation to reduce the likelihood of military confrontations. However, as noted above, in the next years the military plans being implemented by states are likely to create a more confrontational approach, including at sea.

In these circumstances a more limited approach focused on naval risk reduction could be explored as a stand-alone measure, separate from the continuous discussion of updating the Vienna Document. This could help reduce some of the risks associated with encounters between naval surface ships and between ships and aircraft.


Elements of a naval risk reduction architecture

A coherent risk reduction mechanism could have three dimensions.

First, to correct the deficit in dialogue between navies, a framework for dedicated navy-to-navy contacts could be created to improve understanding of the current conditions in European waters—including the potential for different kinds of risk to arise from naval activities.

Second, European navies already participate in roughly a dozen risk reduction agreements of different kinds, almost all of which are bilateral and based on the 1972 US–Soviet Incidents at Sea (INCSEA) Agreement. These agreements are intended to guide commanders on the appropriate way to react to unexpected, but not necessarily hostile, incidents in international waters or above them. Although these agreements are very similar in both form and content, they are not identical. A consolidated document, open to all navies to sign, could promote adherence to the most current and updated INCSEA agreements.

The consolidated document could incorporate the most current standards by examining the initiatives taken by Asian navies, where a Code for Unplanned Encounters at Sea (CUES) was elaborated after 2014 to provide a coordinated means of communication to maximize safety at sea. The document could contain safety procedures, a basic communications plan and basic manoeuvring instructions for naval ships and naval aircraft during unplanned encounters at sea.

The consolidated agreement would supplement bilateral arrangements, not replace them. As noted above, naval operations create risks of different kinds. Some of them are inadvertent, stemming from the irresponsible actions of an individual commander, lack of knowledge or poor training among officers or crew, or the use of different and incompatible signals. These risks can be offset by measures to ensure long-standing rules of seamanship and nautical practice are properly understood and rigorously applied.

The most serious naval risks are the result of deliberate actions, and they are intended to create a certain jeopardy in order to send a signal of some kind. Responding to the use of live fire, deliberate ramming and the capture and detention of ships with their crew in the eastern part of the Black Sea in November 2018, for example, could only be addressed by measures that go beyond technical risk reduction.

In between inadvertent and hostile incidents, other types of deliberate risks can occur. For example, when naval vessels are placed in front of foreign ships or inside foreign naval formations to cause obstruction; when ships or aircraft deliberately move to within a very short distance of each other; or in certain cases where on-board radars, jammers and decoys interfere with the navigation or communications systems of other ships or aircraft.

Third, a related element of risk reduction is the development of a ‘risk matrix’ to determine the characteristics of different naval incidents based on whether they are deliberate or inadvertent, and on their timing, nature and location. Combining appropriate collective and bilateral measures to address the different risk categories with a method for allocating an incident to the right measure would make a coherent risk reduction architecture available to states.

One task that could be explored by the naval dialogue framework mentioned above would be to assess the feasibility of a ‘traffic light’ system for sorting incidents into one of three categories according to agreed standards and guidelines.


1. Green light incidents. Incidents considered routine, but which could involve a degree of risk to the safety of vessels or crew. These would not require any specific action to be taken, but it could be useful to store information about them systematically to allow further analysis if needed.

2. Orange light incidents. Incidents considered to be serious or significant enough to justify more detailed examination in a formal setting—such as an annual review meeting—where there could be discussion of how such incidents could be better managed. If systematic analysis of information collected indicated a potentially disturbing pattern of ‘green light’ incidents then the discussion of that finding could move to the ‘orange light’ forum.

3. Red light incidents. Incidents considered particularly dangerous and that require immediate action would need to be addressed through a dedicated bilateral channel to avoid escalation or repetition and to manage political fallout.


In Europe, the feasibility and value of an integrated approach to risk reduction building on navy-to-navy dialogue, a stand-alone multilateral INCSEA agreement and strengthened bilateral instruments to address more serious risks could be the subject for a focused discussion in the OSCE. These measures have a value per se given the increasing number of incidents being recorded at sea. As progress on either conventional arms control or a modernized CSBM catalogue seems very unlikely, risk reduction measures may help to promote intergovernmental dialogue on military stability. This is also an opportune moment to encourage other regions to share best practices. In particular, Asian countries that have recent experience of risk reduction at sea could be invited to join that discussion.


Read further analysis in SIPRI's latest Policy Paper, 'Reducing military risk in Europe'.


Dr Ian Anthony was the Director of SIPRI’s European Security Programme.