26 May 202017:19

Treaty on Open Skies: Questions and Answers


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The Ministry of Foreign Affairs of the Russian Federation has received many questions in the context of the US withdrawal from the Treaty on Open Skies. We are publishing answers to the most topical questions.

The Treaty on Open Skies (OST) is an agreement aiming at confidence building in military sphere. The Treaty is filled with complicated technical provisions concerning observation aircraft and sensors, sensors certification, observation missions planning, observation flight quotas, maximum observation flight distances, etc. Obviously, this is why the public at large, as well as the political and parliamentary circles of its States Parties have not paid too much attention to the Treaty for almost 30 years.

Today, media outlets are talking about the Treaty more often due to the fact that the issue of the US withdrawal from the Treaty has been raised. However, some publications contain factual inaccuracies or unbalanced approaches that reflect the views of the Treaty opponents in the United States, but disregard the positions of others, including the position of the Russian Federation. This unofficial document is based on facts, rather than speculations, and aims at rectifying this situation.


Question: Is it true that the Treaty on Open Skies benefits Russia more than other States Parties, including the United States?

Answer: If this were the case, it would not take the Russian Parliament nine years to reflect on the Treaty before ratifying it. All those years our Western partners urged us to complete the ratification process more quickly. The opening of Russian territory to aerial observation was a very difficult decision, especially since Russia has to host many more flights than any other State Party (during our OST membership we have hosted over 500 observation missions).

The Treaty is based on the principle of equality of rights and obligations. Each State Party has the right to conduct a number of observation flights over the territory of any other State Party equal to the number of observation flights which that other State Party has the right to conduct over it.

At the same time, however, Russian aircraft fly not only over the United States (annually, it hosts on average from five to six our missions), while Western partners mostly focus their interest on Russia, Belarus and, partially, Ukraine. They conduct very few flights over other countries (Bosnia and Herzegovina, Georgia). By the way, the United States conducts about twice as many flights over Russian territory, either by itself or together with other States Parties, as Russia does over the US territory.

It is also important to note that the Treaty allows its States Parties to obtain observation flight data from each other. And, if one State’s aircraft flies over Russia, then that State can share the information, for example, with its allies. NATO countries do not fly over each other. Thus, we have no one to obtain these data from. This circumstance largely shifts the balance of information obtained in the framework of the Treaty not to the Russian advantage.

Nevertheless, these problems notwithstanding, Russia believes that the Treaty is useful for all its States Parties. It contributes to confidence-building and, therefore, to the European security.

This is why when, in the summer of 2014, politicians in Kiev and in Western capitals were loudly claiming that there was a “build-up of Russian forces on the Ukrainian border”, Russia did not object to the conduct of the Open Skies missions in this area. 19 observation flights were conducted, and the data obtained during these flights convincingly proved that there had been no such “build-up”.

This and other examples attest to the fact that for many years Russia has been making every effort to preserve the Treaty’s viability, even when concessions have to be made for this purpose. This fact is inconsistent with the statements saying that Russia is taking unilateral advantages allegedly stemming from the Treaty.

In addition, we have to maintain in the state of constant readiness two points of entry/exit, 13 Open Skies and refuelling airfields, as well as 28 alternate designated airfields, to facilitate almost weekly observation flights conducted by the OST States Parties over the Russian Federation.

These statistics are simply not comparable with the parameters of the other States Parties in terms of their contribution to the OST implementation.

Question: This could be the case in quantitative terms. However, Russia was the first OST State Party to develop digital sensors, wasn’t it? It just has “sharper eyes” and hence collects better information.

Answer: The idea of developing digital sensors was put forward by the United States when industry started to reduce the manufacture of film for aerial survey.

It should also be pointed out that the Treaty restricts the “visual acuity” you mentioned, that is, the ground resolution. It must be no better than 30 centimetres for both analogue and digital sensors. By creating a digital camera, Russia has not acquired the ability to receive more detailed images.

The capabilities of the sensors are inspected during the certification of every new aircraft and new sensor configuration. The minimum height for operating a sensor that complies with the Treaty restrictions is set taking into account the conclusion of the States Parties experts.

Question: But probably there are ways for Russia to receive information that goes beyond the OST restrictions or to covertly operate sensors?

Answer: This is exactly what the Soviet Union (and possibly it was not the only one) was concerned about when the Treaty was drafted. This is why the Treaty and the subsequent related decisions provide for the measures that prevent this from happening. Observation aircraft and sensors are meticulously checked to this end during both the certification process and the pre-flight inspections.

For example, the observation aircraft camera windows have special covers that preclude unwarranted filming. All covers either have special external seals or are structured in a specific way so that they can be dismantled and installed only on the ground. The Treaty procedures provide for the inspection of these covers at all transit airfields, after the aircraft’s arrival at the point of entry and at the airfield from which it will take off for the observation flight, so as to make sure that the sensors were not used during the transit flights.

In addition, such inspections are carried out not only with regard to the aircraft and its sensors but also to the relevant software used to convert the initial data received on board to a format comprehensible for all States Parties.

Furthermore, of course, during the observation mission over the territory of an observed Party, representatives of the observed Party accompany the Open Skies mission members and fly on board the observation aircraft in the course of its mission in order to ensure compliance with the Treaty.

Question: Why does Russia film the critical infrastructure in the United States and Europe? US Secretary of State Mike Pompeo said it was being done for targeting it with Russian precision-guided weapons.

Answer: When the Treaty was drafted, it was the United States that insisted that the entire territory of the States Parties without exceptions should be open to observation flights. However, it clearly had the Soviet Union and later Russia in mind, forgetting about the principle of reciprocity. While exercising its rights under the Treaty, Russia has always acted strictly in compliance with its provisions. The United States has never filed any complaints against us.

As for the United States, believe us that its observation aircraft film not only parks and beaches when overflying Russia, but also a great number of other facilities, including civilian infrastructure. Washington could probably share the list of those facilities, using this occasion to refresh its own memory about it as well.

Question: You have improperly placed a restriction on observation flight distance over the Kaliningrad region. This violation makes it impossible to observe Russia’s entire territory using the agreed-upon number of flights and reduces the effectiveness of the observation. Are you trying to hide some military facilities located near Kaliningrad from Open Skies aircraft cameras?

Answer: In reality everything is much simpler. Between 2012 and 2014 some of our partners, who have the right to conduct observation flights from the Open Skies airfield in Kubinka near Moscow with the flight distance of up to 5,500 km, used a significant part of this distance (about 1,600 km) to overfly the Kaliningrad region. They repeatedly crossed it back and forth, thereby creating problems for the use of the region’s limited airspace and for the operation of the region’s only international airport, Khrabrovo Airport (slides 1 and 2). This also entailed serious financial costs. Our attempts to come to an agreement on exercising some reasonable restraints were unsuccessful. That is why we had to minimize costs by declaring the maximum flight distance over the Kaliningrad region (500 km). It contradicts neither the Treaty nor the subsequent decisions made by its States Parties.

Restrictions on the maximum flight distance over the Kaliningrad region were established in line with the OST provisions (Annex E, paragraph 4 and subparagraph 5 (A)) and with the OSCC Decision No. 3/04 (subparagraphs 1(a), 1(b) and 1(c)). The current procedures were introduced taking into account the right of a State Party to additionally designate Open Skies airfields and to establish the maximum flight distance for them. This procedure does not increase the number of flights that provide for the observation of Russia’s entire territory (as the total flight distance of 5,500 km remains). It increases effectiveness of the observation of territory of the Kaliningrad region as compared to the rest of the Russian territory and the territory of other States Parties, including our neighbors (Poland, Lithuania, Latvia, Estonia). As we understand, our Western colleagues, including the US, have no complaints against them. At the same time, during each observation flight the flight distance of 500 km allows for the observation of any point of the Kaliningrad region, even of points most distant from the Open Skies airfield. In other words, the initial effectiveness of observation is maintained.

Finally, it should be noted that in February 2020 Russia allowed the joint mission of US, Lithuania and Estonia to overfly the Kaliningrad region with the flight distance of 505 km (slide 3). We hope that this goodwill gesture will pave the way for an arrangement that would respect the particular nature of observation flights over this region.

Question: But apart from Russia no country has established such sub-limits on flight distance over parts of its territory, isn’t it?

Answer: We established these restrictions based on the Kaliningrad region’s geographical features (it is a semi-exclave separated from Russia’s mainland), and on a precedent created by our US colleagues when they established the maximum flight distance for the Alaska semi-exclave.

Let’s take a look at how flights over Alaska are conducted and compare our approaches: (slide 4)

– the Kaliningrad region is a semi-exclave of the Russian Federation, just as Alaska is a semi-exclave of the United States of America;

– As in Alaska, an Open Skies airfield has been designated for observation of the territory of the Kaliningrad region;

– As in Alaska, a maximum flight distance has been established for that airfield, satisfying subparagraph 5(A) of Annex E to the Treaty.

As you can see, the approaches used for the observation of the compared territories are identical.

However, if we compare the area of a territory the image of which can be captured during one observation flight, assuming the maximum swath width, from 77 to 98 per cent of the territory in the Kaliningrad region is covered against just 2.7 per cent in Alaska (slide 5). Therefore, the effectiveness of each observation flight over the Kaliningrad region is from 28 to 36 times higher than over the territory of Alaska.

Question: Why does Russia not allow to conduct observation flights in the 10-kilometre zones near the Russian-Georgian border?

Answer: Your very question reflects the essence of the problem. It shows the Western perception of Abkhazia and South Ossetia as Georgian regions. Having recognized them as independent states, Russia had to comply with the provisions of Article VI, Section II, Paragraph 2 of the Treaty stipulating that the flight path of an observation aircraft shall not be closer than 10 kilometers from the border with an adjacent State that is not a State Party. Thus, the problem has political root causes. It is obvious that it is impossible to settle political disagreements using the OST instruments. It was not simply designed for it.

At the same time, the area of 10-kilometre zones is rather small (it amounts only to 0,02 percent of the total area of the Russian territory (slide 6)) and technically, using certain sensors configurations, it is possible to reliably obtain images of these zones without flying over them. 

Meanwhile, the entire territory of Georgia is inaccessible to Russian Open Skies missions as well as to multi-state missions with Russian participation. Thus, Georgia is in violation of the key OST provisions (Article I, Paragraph 1 and Article III, Section I, Paragraph 2), stipulating that the Treaty is designed for the conduct of observation flights by States Parties over the territories of other States Parties, and that each State Party shall be obliged to accept observation flights over its territory. However, it appears this blatant violation never bothered the US or other advocates of the “impeccable implementation” of the Treaty even when in 2018 no OST observation flights were conducted due to Georgia’s destructive policy. Obviously, regardless of their thunderous declaration about the Treaty’s value for security architecture in the region from Vancouver to Vladivostok, they are ready to sacrifice this agreement for the sake of hyping Tbilisi’s political ambitions and push it towards confrontation with Russia.  

In April 2018 in order to preserve the Treaty and overcome the deadlock we cancelled restrictions on flights in the 10-kilometre zones along Russia’s borders in the Caucasus. At the same time, we reserved the right to revisit the issue in the future and warned that a permission to conduct observation flights in the aforementioned zones would become permanent only if Georgia fulfills its obligations on accepting Russian missions in good faith. This is an integral part of Russia’s statement.  

Unfortunately, Tbilisi’s destructive position has not changed as of yet. As a result, Russia was forced to deny an observation flight in 10-kilometre zones during the joint mission of Sweden, Germany and the US over our territory in April 2019. 

The resumption of the OST observation flights in 2019 after a year of suspension caused by Georgia’s destructive position was made possible entirely owing to Russia’s responsible approach. We did not ask for a quota for flights over Georgia even though we had every right to do so.

Russia is ready to allow observation missions to these zones on condition that Georgia is ready to give up its current position which is inconsistent with the key provisions of the Treaty, and to allow Russian flights over its territory. Actually, an option of a “technical” resolution regarding allowing observation flights without prejudice to political views of the Parties on the status of Abkhazia and South Ossetia was considered in 2018 in the US Department of State report on Adherence to and Compliance with Arms Control, Nonproliferation, and Disarmament Agreements and Commitments. Regretfully, Washington prefers to forget this.

We call on our partners not to politicize the Treaty and to contribute to the search for a solution to existing problems. 

Question: The US also accuses Russia of using the Treaty on Open Skies to impose on its partners its stance on the status of Crimea. You have designated an Open Skies airfield on the territory of the peninsula, haven’t you? 

Answer: In 2014, Crimea and Sevastopol joined Russia based on the expression of the people’s will. Our country takes a responsible attitude towards its obligations under the Treaty on Open Skies, and therefore it sent to all States Parties the relevant notification which contained the information necessary for conducting observation flights over the peninsula. It is up to our colleagues to decide whether to exercise this right or not. By the way, if we hadn’t done this, the US would have accused Russia that, in this case, it had allegedly concealed military facilities in Crimea from observation.

Question: The US Department of State recent Executive Summary of the 2020 Adherence to and Compliance with Arms Control, Non-Proliferation and Disarmament Agreements and Commitments (Compliance Report) issued in April 2020 mentions one more Russian OST violation – denying an agreed-upon US-Canadian flight segment over “TSENTR-2019” military exercise in September 2019. What can you say in this regard?

Answer:  The Russian Federation completely fulfils its obligations to ensure transparent military activity, including military exercises. We intend to adhere to this practice in the future, including within the Treaty on Open Skies.

This is evidenced by the fact that Russia fully approved the US-Canadian mission plan (both its first and second flight segments) without making any changes.

A subsequent ban by air traffic control authorities on conducting the second flight segment on 20 September was solely motivated by the need to guarantee flight safety in a highly complicated situation in the airspace over the exercise area.  The dynamics of the exercise of such a scale, which involved diverse aviation forces, air defense forces and equipment, did not allow air traffic control authorities to ensure safe airspace for the planned Open Skies flight.

Members of the Russian escort team made every effort to organize the conduct of the second observation flight segment. We were ready to offer new dates for its conduct and to increase its duration in excess of the Treaty’s timeframes, that is, for the period of delay. However, the observing Parties turned down our proposals and, therefore, the second observation flight segment was not conducted.

In our opinion, it would have been highly irresponsible to endanger members of the observation mission. By the way, other States Parties often use this argument, while refusing to allow Russia to conduct observation flights.

Question: But, unlike Russia, Western States Parties do not violate the Treaty. At least, the above-mentioned Compliance Report of the US Department of State provides exactly this assessment.

Answer: First of all, it should be noted that independent US OST experts, including those who directly monitored compliance with it, repeatedly voiced at Congressional hearings and other venues their disagreement with the interpretation of Russian actions as “violations” of the Treaty.

Why are these accusations fabricated? On the one hand, this can probably be explained by a desire to divert public attention from the truly serious violations of the Treaty and failure to respect its provisions by the United States, their allies and “client” states. On the other hand, this can be explained by a negative attitude of some Congress members and the US military-political establishment against the Treaty itself, their striving to fabricate “grounds” for their own efforts to wreck yet another military-political agreement.

Unfortunately, the report, as usual, glosses over problems regarding US compliance with the Treaty.

First. In 2015, the United States failed to ensure the safe arrival of Russian An-30B observation aircraft at the point of entry/exit by refusing to provide the required number of intermediate airfields. The US position has not changed as of yet. This constitutes a violation of the Treaty on Open Skies by the United States.

Second. In 2017, the night-time rest stops for observation aircraft crews at the refuelling airfields Robins, Ellsworth, as well as Travis and Elmendorf were cancelled. This violates the observing Party’s rights to conduct observation flights of the established maximum flight distance taking into account the norms of the crew's workload limits, which directly affects the flight safety.

Third. In violation of the Treaty the United States established the maximum flight distance over the Hawaiian Islands from the Hickam refuelling airfield. However, according to the OST, the maximum flight distance is established only from Open Skies airfields and is calculated by specific rules. The distance limit of 900 kilometres established by the US contrary to the provisions of the OST does not comply with the Treaty in any case as this distance must be at least 1,160 kilometres, if calculated correctly.

Fourth. The United States imposed restrictions on observation flights over the Aleutian Islands, according to which the aircraft of an observing Party always has to remain within the outer border of the adjacent zone, spanning 24 nautical miles from the coast. This restriction, which is not provided for by the Treaty, significantly reduces the effectiveness of the observation flights over the US territory.

Additionally, the absence of the night-time rest stops at the King Salmon and Cold Bay refuelling airfields during observation missions also undermines flight safety because the observation aircraft crews have to work longer shifts, up to 14-16 hours.

Fifth. The United States imposes restrictions on the altitude of the observation aircraft flights over its territory, which is not provided for by the OST and run contrary to the ICAO norms recommending the allocation of a special airspace regime for the military aircraft flights.

We have questions to some other OST States Parties. But we do not consider this to be sufficient grounds for withdrawing from the Treaty, slamming the door. We are ready to discuss mutual grievances, provided that this discussion is conducted on an equitable and mutually respectful basis and will not boil down to categorical demands of concessions from Russia.

Question: Nevertheless, the US administration is planning to withdraw from the Treaty. What are the reasons for it – is it national security concerns or economic considerations, since the manufacturing of sensors, let alone new aircraft, costs a lot of money?

Answer: We have already discussed the issue of national security concerns. They do not seem to be well-grounded, given the extremely strict and precise requirements of the Treaty and of the subsequent decisions. In September 2013, during the first inspection of the Russian An-30B observation aircraft equipped with digital sensors, US experts (the only ones among the representatives of dozens of other States Parties) refused to approve its certification without any explanations. The United States provided its consent only eight months later, having failed to decide what fault to find.

Russia knows that strict compliance with the Treaty requires a lot of money. Not only have we developed digital sensors and modernized our aircraft so as to carry it, but also we created a new observation aircraft, Tu-214ON. Other States Parties are following in our footsteps, in particular, Germany and Romania. They plan preliminary certification of new sensors in October 2020. By the way, the United States have equipped their aircraft with digital cameras as well.

Regrettably, the United States has postponed its certification indefinitely. Economic considerations hardly play a decisive role for Washington. Even if it is unable to modernize its observation aircraft in the medium term, they could possibly discuss the lease or joint use of one of the observation aircraft with the European States Parties.

In our opinion, the real reason is the current US administration’s negative attitude towards arms control in general and, in particular, to the arms control agreements signed by previous administrations. The United States has always advocated the maximum transparency in the military area (if it applies to other countries). It may seem paradoxical, but the very possibility of accepting observation over its territory is often perceived almost as a threat to its national security, as the erosion of its sovereignty or simply as an affront to its national pride. As of now, such observation possibilities are granted only under two treaties: the New START Treaty and the Treaty on Open Skies. Their fate is vague because of Washington’s ambivalent position.

Frankly speaking, such an attitude towards the Treaty on Open Skies is reminiscent of the USSR position between the 1960s and early 1980s, when the Soviet Union considered verification that is not linked to real disarmament as legalized espionage. But at least we had a reason for thinking so: regular intrusions by the U-2 spy planes undermined trust in the idea of “Open Skies” for a long time. However, the current US approaches seem to point out the inconsistency and incoherence of its foreign policy (we should like to remind that the aforementioned idea was proposed by President Dwight Eisenhower, and the Treaty itself was signed by President George H. W. Bush. By the way, both were Republicans). Moreover, these approaches question the US ability to honor its commitments and the sincerity of calls for military transparency, for example, through the modernization of the Vienna Document.

Question: Who will lose the most from the collapse of the Treaty on Open Skies? Is there any replacement for it, for example, satellite images?

Answer: The states that have cutting-edge means of national technical verification (primarily satellites) may be able to partly replace the information previously provided under the Treaty.  But only partly, as it is much more difficult and expensive to retarget satellites and hence change their orbits than to send an observation aircraft. Most importantly, unlike the satellites, aircraft provide an opportunity “to take a look under the clouds”.

Those European States that do not have satellites will face more problems. They probably should not expect the United States to generously share its satellite images with them.

At the same time, Washington itself should not harbor too much hope of maintaining access to all data received under the Treaty if it withdraws from it.

If we look at the bigger picture, it is necessary to admit that all current OST States Parties and ultimately European security as a whole will be among the losers. First of all, the Treaty contributes to de-escalation of tensions and prevents any misinterpretation of the Parties’ military intentions, which is exactly what NATO constantly urges us. Second, it is a crucial instrument of military-to-military contacts and cooperation, which in itself facilitates confidence-building. In light of the obvious shortage of common European dialogue platforms on military security, it will be very difficult to make up for the loss of this vital channel of professional communication. Finally, generally less openness leads to less confidence and, consequently, to less security, which will have to be ensured through other, more expensive methods.

We hope that political realism and constructive spirit of the OST States Parties will prevent this from happening.

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