Facility Observation Overflights under the Open Skies Treaty
Open Skies flight crew checks aircraft sensors.
The Open Skies Treaty allows States Parties to fly over the entire territories of other States Parties and to collect imagery for the purpose of promoting greater transparency and openness concerning the military affairs of the participating States of the Organization for Security and Cooperation in Europe (OSCE). The treaty was signed in 1992 and is intended to strengthen peace and security “from Vancouver to Vladivostok.” The treaty entered into force on January 1, 2002.
Open Skies observation flights are flown using unarmed, certified aircraft equipped with treaty-specified imaging sensors. Currently, Open Skies aircraft are equipped only with optical wet film panoramic and framing cameras, and with video cameras with real time display. Each of these cameras has a resolution limit of 30 centimeters, and pictures of this resolution must be taken within a 50 kilometer (31 mile) range of each side of the agreed flight path. Although the treaty also specifies that infrared line-scanning devices (resolution limit: 50 centimeters) and sideways-looking synthetic aperture radar (SAR) (resolution limit: 3 meters) may be used, no States Parties have yet implemented these imaging sensors.
During an Open Skies observation fight, any area or facility located on the territory of the observed Party may be overflown and imaged. The flight path, although agreed prior to take-off, may be restricted only for flight safety reasons – not for concerns relating to national security. Copies of the imagery data collected during an observation flight may be acquired by any of the States Parties to the Open Skies Treaty in addition to the observed and observing Parties themselves.
In the United States, the Open Skies Division at the Defense Threat Reduction Agency (DTRA) has developed an early warning notification system to keep U.S. facilities informed about when they could be overflow and imaged during an Open Skies observation flight. The system sends multiple messages throughout the mission to subscribed facilities regarding the status and location of the Open Skies aircraft.
The first message is sent shortly after the observing Party arrives in the United States. Upon their arrival, the observing Party provides a proposed observation flight plan to U.S. representatives. As the observed Party, the United States may either accept the proposed plan or propose changes in accordance with treaty provisions.
Open Skies crew member monitoring the flight path and sensor data.
When a mission plan is accepted, flight path details are entered into the Passive Overflight Module (POM). This database enables DTRA personnel to identify which subscribed facilities are located along the flight path and could potentially be within range of aircraft sensors.
The period of time between the arrival of the observing Party and the completion of the observation flight shall not exceed 96 hours.
The Telephone Notification System (TNS) and Defense Messaging Service (DMS) transmit notifications to facilities by email and voicemail messages. U.S. officials estimate that notified facilities will have a maximum of 24 hours advance notice prior to being overflown
Given the short amount of time available for facilities to prepare for being overflown during an Open Skies observation flight, it is recommended that facility staff develop an arms control security countermeasures plan that can be implemented on short notice. To develop this plan, facility staff should carefully assess the potential risks associated with Open Skies observation flights. Outdoor activities associated with research and development programs that test, evaluate, and modify aircraft, helicopters, ships, tanks, and other vehicles are subject to imaging. Signatures or indicators such as power sources, ventilation systems, cooling ponds, and pollution-affected vegetation could also potentially reveal proprietary, national security-related, or other sensitive information to a highly skilled analyst.
Certain types of facilities such as satellite, rocket, and missile launch facilities, may have ongoing or scheduled activities that might interfere with aircraft navigation or endanger flight safety. Such activities may need to be postponed. In most cases, potential problems can be avoided by simply covering an item of concern or moving it inside prior to an observation mission flight. In other cases, additional security countermeasures may need to be applied.
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