3

Current Russian and U.S. Ballistic Missile Defense Systems

To counter the general threats to international security due to proliferation of missiles and missile technologies, the United States and the Russian Federation have independently deployed limited ballistic missile defense (BMD) systems.

A ballistic missile defense system is an interconnected set of sensors, analytics, and countermeasures that target one or more attack missiles to prevent them from harming their intended targets. The sensors may be based on the ground, at sea, in the air, and/or in orbit, typically using radar and infrared detection and tracking. The analytics interpret the sensor data, identifying attack missiles and determining their position and trajectory. The countermeasures may be interceptor missiles based on the ground or in the air, or directed energy beams in close proximity to the attack missiles. The countermeasures are meant to disable, disrupt, or destroy the attack missiles; and the type of BMD system developed and deployed, including sensors and countermeasures, is generally selected and designed to counter a particular type of attack missile, that is, short-range, intermediate-range, or intercontinental.

U.S. regional and Russian BMD systems, both current and planned for deployment, include space-based elements for launch detection and initial track determination, radar systems for midcourse tracking and final target point determination, and interceptors for inbound missile destruction. As described below, satellite systems operate from both geosynchronous and highly elliptical orbits. Radar systems and interceptors include both land- and sea-based elements. The deployed and planned interceptors are designed to disable intermediate- and medium-range missiles.

THE UNITED STATES’ REGIONAL BALLISTIC MISSILE DEFENSE SYSTEMS

Satellite Systems

Satellite systems consist of the satellites themselves, including the power, sensor, communication, and maneuvering systems onboard the satellites, and the ground-based infrastructure that sends and receives signals from the satellites and interprets the data collected. All of these elements are needed for a satellite system to be of use in regional BMD systems.

In designing sensor systems on satellites, there is a trade-off between resolution and coverage in space and time specifically to ensure adequate sensitivity and timely response to a threatening launch at any time from a wide variety of potential locations across the globe. Satellites

that image at high spatial resolution may not be suitable for providing wide-area coverage with rapid response, unless a large constellation of satellites is deployed. Large numbers of satellites imply large costs, unless satellite architectures are significantly changed, for example through deployment of small satellites. Such deployments have yet to be proven effective for the purposes of space surveillance being considered here, so there remains a technical tension between resolution and coverage.

The current constellation of U.S. early warning satellites is a mixture of the first elements of the Space-Based Infrared System (SBIRS)⁶⁴ and the remaining capabilities of the Defense Support Program (DSP) satellites.⁶⁵ The SBIRS constellation currently includes two geosynchronous (GEO)^* satellites and two SBIRS payloads in highly elliptical orbits; three more SBIRS GEO satellites should be in orbit and operational by 2020. The first of the 23 DSP satellites was launched in 1970, and the last was launched in 2007. The last DSP satellite and all but a handful of the others are in operation today, and all are beyond their designed operational lifetimes.

The SBIRS GEO payload includes scanning and staring sensors, providing improved infrared sensitivity and more-timely coverage than the legacy DSP satellites. SBIRS scanning sensors provide wide-area surveillance of missile launches and natural phenomena, while the staring sensors are used to observe smaller areas of interest with greater sensitivity.

In addition to these early warning systems, two Space Tracking and Surveillance System (STSS) satellites were launched in 2009 into low-Earth orbit (approximately 1,300 km), at a 58-degree inclination, with an orbital period of 120 minutes. These satellites have demonstrated the ability to hand off initial detection and tracking data to sea-based systems, and provide better angular resolution of initial tracking data than prior satellite systems. STSS satellites working with Aegis systems demonstrated “launch-on-remote” capability, providing additional time to intercept.^†

A planned follow-on program to STSS was known as the Precision Tracking Space System (PTSS),^‡ consisting of nine infrared satellites operating at an altitude of 1,550 km around Earth’s equator; it was cancelled in 2013. The planned system was criticized by the U.S. Government Accountability Office⁶⁶ and a study committee of the National Research Council⁶⁷ for being more expensive than alternatives that would be more effective. The U.S. Missile Defense Agency maintained that PTSS could provide useful cueing information to Aegis missile defense systems, but critics noted that (1) SBIRS can provide cueing at no additional cost, and (2) forward-based X-band radars would be more effective and less expensive for tracking. At various times, the agency has also stated that PTSS would provide midcourse discrimination,^§ but the National Research Council study concluded that it was inadequate for that mission. With the planned equatorial orbits and the limitations of the satellite sensors, PTSS would not provide discrimination and would only provide tracking near the equator. For full constant coverage worldwide from low--

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^* Geosynchronous orbits are a little less than 36,000 km above Earth’s surface.

^† Launch on remote refers to the ability to observe a threat using a sensor that is remote from an interceptor, transmit the relevant information for an initial target solution to the interceptor launch system, and launch the interceptor. Engage on remote, discussed below, refers to the ability to launch and direct an interceptor to the vicinity of a threat missile based on a sensor that is remote from the interceptor (i.e., without the intermediate launch-on-remote step of transmitting the sensor data to the interceptor site prior to launch).

^‡ Missile Defense Agency, U.S. Department of Defense, 2013, “Fact Sheet: Precision Tracking Space System,” available at https://www.mda.mil/global/documents/pdf/ptss.pdf, accessed on February 21, 2019.

^§ Discrimination is the ability to distinguish the target, which is the portion of the missile containing the warhead, from debris and decoys.

Earth orbit, the system would need at least 24 satellites. Although these analyses found that PTSS had many shortcomings, the capabilities that the program sought to provide could be quite valuable, as discussed in Chapter 5. As of the publication of this report, no alternatives to the cancelled capabilities have been identified or funded.

Radar Systems

U.S. radar systems for long-range missile tracking are located at Clear Air Force Station and Eareckson Air Station, Alaska, United States; Royal Air Force Fylingdales Station, United Kingdom; Thule Air Base, Greenland; Joint Base Cape Cod, Massachusetts, United States; and Beale Air Force Base, California, United States. These are large, solid-state phased-array radar systems. Four of these systems (Fylingdales, Thule, Clear, and Cape Cod) specifically received upgrades to function in a ballistic missile defense mode, and are now referred to as Upgraded Early Warning Radar. Typical ranges for these radars are approximately 4,800 km, and they are stated as able to track hundreds of objects simultaneously. Only one of these radars, the one based in Fylingdales, is relevant to the U.S. regional BMD system.

The United States has a Sea-Based X-Band Radar (SBX-1) for the purpose of homeland missile defense and has been included in this description of the U.S. BMD systems for informational purposes. The SBX-1 is a radar array mounted on a converted mobile drilling rig based off of Alaska. The X-band phased array can detect small objects at a range of 4,000 km, although the field of view is limited. The United States has other transportable X-band and S-band radars that are a part of its regional BMD system. These include the AN/TPY-2 X-band radars, which can be deployed in forward-based mode for early detection and tracking or in terminal mode as part of Terminal High Altitude Area Defense missile deployments; and the AN/SPY-1 S-band radars, which are part of the Aegis Combat System. Terminal defenses attempt to intercept threat missiles close to their intended target in the last phase of flight.

Interceptors

Deployed defenses for U.S. regional BMD consist of sea- and land-based interceptors for both midcourse and terminal phases of flight.^* At sea, as of the end of the fiscal year 2018, the United States had deployed 38 Aegis ships bearing 193 interceptors. By the end of fiscal year 2024, the United States plans to increase these numbers to 59 Aegis ships, with 150 SM3-1/1A

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^* In addition to interceptors deployed as part of U.S. regional BMD, there are other assets associated with homeland defense. The National Missile Defense or Ground-based Midcourse Defense (GMD) system that the United States has deployed is intended to protect the U.S. homeland against “a limited intermediate and intercontinental ballistic missile attack from nations such as North Korea and Iran.” (Arms Control Association, updated 2019, “U.S. Missile Defense Programs at a Glance,” available at https://www.armscontrol.org/factsheets/usmissiledefense, accessed on January 22, 2019.) To counter such missile threats, the GMD system launches a ground-based interceptor (GBI) to destroy the threat warhead in midcourse, outside the atmosphere. The interceptors are silo-based, three-stage missiles with a “hit-to-kill” component called an exoatmospheric kill vehicle. The United States has deployed 40 GBIs based at Fort Greely, Alaska, and 4 at Vandenberg Air Force Base, California. (Missile Defense Agency, U.S. Department of Defense, 2018, “The Ballistic Missile Defense System,” available at https://www.mda.mil/system/system.html, accessed on October 24, 2018.) An additional 20 interceptors are planned for Fort Greely by 2020. (Judson, J., February 1, 2018, “Boeing Wins $6.6B Deal to Support Missile Defense System, Build More Interceptors,” DefenseNews, available at https://www.defensenews.com/land/2018/02/01/boeing-wins-66-billion-deal-to-support-missile-defense-system-build-more-interceptors/, accessed on October 24, 2018.)

interceptors, 253 SM3-1B interceptors, and 17 SM3-IIA interceptors, for a total of 420.⁶⁸ The 6.55m, three-stage SM-3 interceptors are intended to defend against short- to intermediate-range ballistic missiles.

NATO is currently deploying SM3 interceptors in the Aegis Ashore system as part of the European Phased Adaptive Approach. The Aegis Ashore site in Deveselu, Romania, with 24 SM31B interceptors, guided by the AN/SPY-1 radar, became operational in 2016. By 2020, a similar system is to be deployed at Redzikowo, Poland, with SM3-1B and SM3-2A interceptors and a slightly upgraded radar and control system.⁶⁹

MISSILE DEFENSE SYSTEMS OF THE RUSSIAN FEDERATION

The Russian Federation is embarking on an ambitious plan to upgrade all elements of its ballistic missile defense system by 2020.

For defense of Moscow, Russia brought the A135 system into operation in 1995. This system consists of 68 nuclear-armed interceptors for both intermediate- and medium-range ballistic missile threats, and a set of phased-array radar stations for missile tracking. The radar systems comprise long-, medium-, and short-range phased arrays. The A135 system was deployed when the Anti-Ballistic Missile Treaty was in force, which limited the deployed system to 100 interceptors. The treaty ceased to be in force when the United States formally withdrew in 2002. Some of the interceptors in the A135 system have been upgraded for the modernized A235 system. The whole system is to be further upgraded by 2020 with up to 100 interceptors.

Satellites

The Russian Unified Air Defense System includes the Missile Early Warning System (MEWS) and the Outer Space Defense System. MEWS has space- and ground-based components.

Current Russian space-based missile warning satellites include residual capability from highly elliptical orbiting Oko satellites, with limited coverage (hours per day). Russia also has geosynchronous satellites providing coverage over the continental United States, but these older infrared systems reportedly have ceased normal operation.

The Russian committee reported that Russian plans call for a constellation of 12 next-generation Edinaia Kosmicheskaia Sistema (EKS, or Unified Space System) satellites in both geosynchronous and highly elliptical orbits to replace the Oko satellites. The first satellite of this system was launched in 2015 and the second was launched in 2017.^* The new infrared sensing satellite system is to be closely integrated with ground-based early warning radars to provide an extensive picture of global missile launches, reportedly able to detect intermediate-range and medium-range missile launches in addition to intercontinental ballistic missiles (ICBMs). The EKS satellites are also to serve as a key element of the command and control system, thereby aiding strategic stability.

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^* In a 2019 report, CNA cited TASS reporting that two early warning satellites would be launched annually beginning in 2018 and that 10 satellites would be launched by 2022, but no launches took place in 2018 or in the beginning of 2019. See Zak, A., 2019, “Russian Military and Dual-Purpose Spacecraft: Latest Status and Operational Overview,” available at https://www.cna.org/CNA_files/PDF/IOP-2019-U-020191-Final.pdf, accessed on August 6, 2019, 15.

Radars

As of 2015, Russia had put into operation six Voronezh early warning radar installations on Russian territory along its periphery. The radar systems are located in Irkutsk, Eniseysk, Barnaul, Kaliningrad, St. Petersburg, and Krasnodar. Voronezh radars are highly modular and more quickly constructed than previous radar facilities. They are reported to have a ballistic target detection range of between 4,500 and 6,000 km (see Table 3-1) and are part of the S-400 and S-500 anti-aircraft, anti-missile systems.

In addition, the capabilities of the fixed ground-based MEWS element may be enhanced with the deployment of mobile radar stations on sea-borne, motor vehicle, and rail platforms. These will utilize the modular, prefabricated radar station technologies that are the basis of the new advanced containerized assets.

Interceptors

The S-400 is the most advanced anti-aircraft/anti-missile system deployed by the Russian Federation. Although primarily an anti-aircraft system, the S-400 is also designed to intercept ballistic and cruise missiles at ranges of up to 400 km at an altitude of up to 30 km. The system is capable of launching different types of interceptors with a variety of ranges. By 2020, the Russian Federation plans to deploy 28 regiments of the S-400. The interceptors in the S-400 system include the 48N6DM, which operates within a range of 250 km; the 40N6, with a range of 400 km; and the 9M96E and 9M96E2, with a range of 120 km. The 40N6 has an onboard active radar system.

The Russian Federation is developing and plans to deploy 10 regiments of the S-500 system (up to 480 missile interceptors) by 2020 as a complement to, and ultimately a replacement for, the S-400. Each regiment will consist of three battalions, each having one missile interceptor package that includes eight launchers that can be equipped with four interceptors per launcher. The Russian Federation has not disclosed detailed features but has indicated that the new system is designed to be effective against ICBMs in addition to other threats.

The Russian Federation plans, by 2020, to integrate the S-400 and S-500 systems with the Voronezh-type radar systems currently used only for early warning and tracking. This will allow for discrimination of decoys at an earlier stage when the attack missiles can be tracked by the radar system. The S-500 is capable of engaging targets outside of the atmosphere, and could receive its initial firing solution from the Voronezh-type radar systems. Interceptor missiles utilize infrared sensors to target the attack missiles.

Finally, by 2020 the separate planned Moscow defense system will include up to 84 silo launchers with upgraded missile interceptors equipped with both nuclear and conventional warheads (other components of the 2020 Russian system are expected to be deployed only with conventional warheads). These interceptors (designated 53T6 by Russia) are estimated by Russian experts to be capable of intercepting ballistic targets at ranges up to 150 km and altitudes between 5 and 80 km.

SIGNIFICANT CONCEPTUAL DIFFERENCES

It is important to recognize the conceptual differences between Russian- and U.S.-deployed ballistic missile defenses. Russian defenses are deployed to defend Russian territory, while the United States also deploys systems to defend its allies, especially those in NATO.^* This difference has caused some Russian analysts to raise concerns about the ability of such systems, deployed for defense of U.S. allies, including NATO, to have some capability to defend against Russian strategic forces.

Even with regard to defense of national territory, there are conceptual differences. The United States seeks to defend its entire territory against very small attacks by future first-generation North Korean or Iranian ICBMs. In contrast, the Russian system is designed to defend a specified number of military-industrial centers each covering an area of 10,000 km², as well as the national capital (using a separate system). This approximate area corresponds to 100 km-by-100 km, which is the anticipated effective defended area of the S-500 system. These conceptual differences complicate the ability to make direct comparisons between the ballistic missile defense deployments of the two countries.

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^* As noted previously, the analysis in this report excludes battlefield defenses.