Sea-based X-band Radar
Encyclopedia
Radar
Radar is an object-detection system which uses radio waves to determine the range, altitude, direction, or speed of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. The radar dish or antenna transmits pulses of radio...
station designed to operate in high winds and heavy seas. It is part of the U.S. Defense Department Ballistic Missile Defense System.
The Sea-Based X-Band Radar is mounted on a fifth generation Norwegian-designed, Russian-built CS-50 semi-submersible
Semi-submersible
A semi-submersible is a specialised marine vessel with good stability and seakeeping characteristics. The semi-submersible vessel design is commonly used in a number of specific offshore roles such as for offshore drilling rigs, safety vessels, oil production platforms and heavy lift cranes.The...
twin-hulled oil-drilling platform. The hull was originally built at Vyborg
Vyborg
Vyborg is a town in Leningrad Oblast, Russia, situated on the Karelian Isthmus near the head of the Bay of Vyborg, to the northwest of St. Petersburg and south from Russia's border with Finland, where the Saimaa Canal enters the Gulf of Finland...
Shipyard, hull number 101. Conversion of the platform was carried out at the AmFELS yard in Brownsville, Texas
Brownsville, Texas
Brownsville is a city in the southernmost tip of the state of Texas, in the United States. It is located on the northern bank of the Rio Grande, directly north and across the border from Matamoros, Tamaulipas, Mexico. Brownsville is the 16th largest city in the state of Texas with a population of...
; the radar mount was built and mounted on the platform at the Kiewit yard in Ingleside, Texas
Ingleside, Texas
Ingleside is a town in Nueces and San Patricio Counties in the U.S. state of Texas. The population was 9,388 at the 2000 census.Ingleside is also home to Naval Station Ingleside. On August 24, 2005, the BRAC Committee voted to close the base. In 2010, the main base property was turned over to the...
, near Corpus Christi
Corpus Christi, Texas
Corpus Christi is a coastal city in the South Texas region of the U.S. state of Texas. The county seat of Nueces County, it also extends into Aransas, Kleberg, and San Patricio counties. The MSA population in 2008 was 416,376. The population was 305,215 at the 2010 census making it the...
. It is nominally based at Adak Island
Adak Island
Adak Island is an island near the western extent of the Andreanof Islands group of the Aleutian Islands in Alaska. Alaska's southernmost town, Adak, is located on the island...
in Alaska
Alaska
Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...
(though, as of August 2011, has never put into port at Adak) but can roam over the Pacific Ocean
Pacific Ocean
The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...
to detect incoming ballistic missiles. The platform is classed
Classification society
A classification society is a non-governmental organization that establishes and maintains technical standards for the construction and operation of ships and offshore structures...
by ABS
American Bureau of Shipping
The American Bureau of Shipping is a classification society, with a mission to promote the security of life, property and the natural environment, primarily through the development and verification of standards for the design, construction and operational maintenance of marine-related facilities...
and has the IMO
International Maritime Organization
The International Maritime Organization , formerly known as the Inter-Governmental Maritime Consultative Organization , was established in Geneva in 1948, and came into force ten years later, meeting for the first time in 1959...
number of 8765412.
Specifications
- Platform length: 116 meters (380 ft)
- Platform height: 85 meters (280 ft) from keel to top of radar dome
- Platform draft: approximately 10 meters when in motion or otherwise not on station; approximately 30 meters when on station
- Platform stability: remains within 10 degrees of horizontal on station (fully passive stabilization)
- Cost: $900 million
- Crew: Approximately 75-85 members, mostly civilian contractors
- Radar range: 2,000 km
- Displacement: 50,000 tons
Details
The platform is part of the Ground-Based Midcourse DefenseGround-Based Midcourse Defense
Ground-Based Midcourse Defense is the United States system for intercepting incoming warheads in space. Currently, it is a major component of the U.S. national missile defense strategy aimed against ballistic missiles, including intercontinental ballistic missiles...
(GMD) system being deployed by the MDA
Missile Defense Agency
The Missile Defense Agency is the section of the United States government's Department of Defense responsible for developing a layered defense against ballistic missiles. The agency has its origins in the Strategic Defense Initiative, which was established in 1983 and was headed by Lt...
. Being sea-based allows the platform(s) to be moved to areas where they are needed for enhanced missile defense. Fixed radars provide coverage for a very limited area due to the curvature of the Earth
Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...
. The primary task SBX will carry out is discrimination (identification) of enemy warheads from decoys, followed by precision tracking of the identified warheads.
The platform has many small radome
Radome
A radome is a structural, weatherproof enclosure that protects a microwave or radar antenna. The radome is constructed of material that minimally attenuates the electromagnetic signal transmitted or received by the antenna. In other words, the radome is transparent to radar or radio waves...
s for various communications tasks and a central, large dome that encloses and protects a phased-array, 1,800 tonne (4,000,000 pound) X band
X band
The X band is a segment of the microwave radio region of the electromagnetic spectrum. In some cases, such as in communication engineering, the frequency range of X band is rather indefinitely set at approximately 7.0 to 11.2 gigahertz . In radar engineering, the frequency range is specified...
radar antenna. The small radomes are rigid, but the central dome is not - the flexible cover is supported by positive air pressure amounting to a few inches of water. The amount of air pressure is variable depending on weather conditions.
The radar antenna itself is described as being 384 square meters. It has a large number of solid-state transmit-receive modules mounted on a octagonal flat base which can move ±270 degrees in azimuth and 0 to 85 degrees elevation (although software currently limits the maximum physical elevation to 80 degrees). The maximum azimuth and elevation velocities are approximately 5-8 degrees per second. In addition to the physical motion of the base, the beam can be electronically steered off bore-sight (details classified).
There are currently 22,000 modules installed on the base. Each module has one transmit-receive feed horn and one auxiliary receive feed horn for a second polarization, so there are 44,000 feedhorns. The base is roughly 2/3 populated and so there is room for installation of additional modules. The current modules are concentrated towards the center, so as to minimize grating lobes. This configuration allows it to support the very-long-range target discrimination and tracking that GMD
Ground-Based Midcourse Defense
Ground-Based Midcourse Defense is the United States system for intercepting incoming warheads in space. Currently, it is a major component of the U.S. national missile defense strategy aimed against ballistic missiles, including intercontinental ballistic missiles...
's midcourse segment requires. The array requires over a megawatt of power.
In addition to the power consumed by the radar, the thrusters which make the platform self-propelled are all electric and require substantial power (maximum platform speed is in the neighborhood of 8 knots). To support this and all other electrical equipment, the platform currently has six 3.6 megawatt generators (12 cylinder Caterpillar diesels). The generators are in two compartments, one port and one starboard. The maximum power currently drawn is roughly 12 megawatts, and there are plans to expand the number of generators to eight, so that one entire compartment could be lost and the platform would still continue to operate at full capability.
Active Electronically Scanned Array
An Active Electronically Scanned Array , also known as active phased array radar is a type of phased array radar whose transmitter and receiver functions are composed of numerous small solid-state transmit/receive modules . AESAs aim their "beam" by broadcasting radio energy that interfere...
radar is derived from the radar used in the Aegis combat system
Aegis combat system
The Aegis Combat System is an integrated naval weapons system developed by the Missile and Surface Radar Division of RCA, and now produced by Lockheed Martin...
, and is a part of the layered ballistic missile defense (BMDS) program of the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
Missile Defense Agency
Missile Defense Agency
The Missile Defense Agency is the section of the United States government's Department of Defense responsible for developing a layered defense against ballistic missiles. The agency has its origins in the Strategic Defense Initiative, which was established in 1983 and was headed by Lt...
(MDA). One important difference from Aegis is the use of X band in the SBX. Aegis uses S band
S band
The S band is defined by an IEEE standard for radio waves with frequencies that range from 2 to 4 GHz, crossing the conventional boundary between UHF and SHF at 3.0 GHz. It is part of the microwave band of the electromagnetic spectrum...
, and Patriot
MIM-104 Patriot
The MIM-104 Patriot is a surface-to-air missile system, the primary of its kind used by the United States Army and several allied nations. It is manufactured by the Raytheon Company of the United States. The Patriot System replaced the Nike Hercules system as the U.S. Army's primary High to Medium...
uses the higher-frequency C band. The X band frequency is higher still, so its shorter wavelength enables finer resolution of tracked objects. The radar is designed and built by Raytheon
Raytheon
Raytheon Company is a major American defense contractor and industrial corporation with core manufacturing concentrations in weapons and military and commercial electronics. It was previously involved in corporate and special-mission aircraft until early 2007...
Integrated Defense Systems for Boeing
Boeing
The Boeing Company is an American multinational aerospace and defense corporation, founded in 1916 by William E. Boeing in Seattle, Washington. Boeing has expanded over the years, merging with McDonnell Douglas in 1997. Boeing Corporate headquarters has been in Chicago, Illinois since 2001...
, the prime contractor on the project for MDA.
The radar has been described by Lt. Gen
Lieutenant General
Lieutenant General is a military rank used in many countries. The rank traces its origins to the Middle Ages where the title of Lieutenant General was held by the second in command on the battlefield, who was normally subordinate to a Captain General....
Trey Obering (director of MDA) as being able to track an object the size of a baseball
Baseball (object)
A baseball is a ball used primarily in the sport of the same name, baseball. The ball features a rubber or cork center, wrapped in yarn and covered in leather. It is in circumference . The yarn or string used to wrap the baseball can be up to one mile in length...
over San Francisco in California from the Chesapeake Bay
Chesapeake Bay
The Chesapeake Bay is the largest estuary in the United States. It lies off the Atlantic Ocean, surrounded by Maryland and Virginia. The Chesapeake Bay's drainage basin covers in the District of Columbia and parts of six states: New York, Pennsylvania, Delaware, Maryland, Virginia, and West...
in Virginia, approximately 2900 miles (4,667.1 km) away. The radar will guide land-based missiles from Alaska and California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
, as well as in-theatre assets.
The CS-50 semi-submersible platform on which the radar is mounted was built as the "Moss Sirius" at the Vyborg shipyard in Russia for Moss Maritime (now part of the Saipem
Saipem
Saipem S.p.A. is an Italian oil and gas industry contractor. It is a subsidiary of Italian energy company Eni, which owns approximately 43% of Saipem's shares. Saipem has contracted for designing and constructing several pipelines, including Blue Stream, Greenstream, Nord Stream and South...
offshore company). It was purchased for the Sea-based X-band Radar project by the Boeing company, outfitted with propulsion, power and living quarters at the AmFELS shipyard in Brownsville, Texas, and integrated with the radar at the Kiewit yard in Ingleside, Texas.
Adak Island
Adak Island is an island near the western extent of the Andreanof Islands group of the Aleutian Islands in Alaska. Alaska's southernmost town, Adak, is located on the island...
, Alaska
Alaska
Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...
, part of the Aleutian Islands. From that location it will be able to track missiles launched toward the US from both North Korea
North Korea
The Democratic People’s Republic of Korea , , is a country in East Asia, occupying the northern half of the Korean Peninsula. Its capital and largest city is Pyongyang. The Korean Demilitarized Zone serves as the buffer zone between North Korea and South Korea...
and China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
. Although her homeport is in Alaska, she will be tasked with moving throughout the Pacific Ocean
Pacific Ocean
The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...
to support her mission. The name given to the SBX platform, "SBX-1", indicates the possibility of further units of the class; in circumstances when a vessel is required to be continually on duty over a long period of time, common naval practice is to have at least three units of the type available to allow for replenishment, repair and overhaul. Three further platforms of the CS-50/Moss Sirius design were under construction or contract at the Severodvinsk shipyard in Russia as of early 2007, but were configured for oil production. On May 11, 2011, Col. Mark Arn, the SBX project manager for MDA, said that SBX is only one of its kind and there are no current plans for another one. In July 2011, a Missile Defense Agency spokesman explained that other, smaller radars in the Pacific will "pick up the slack" while SBX is in port with its radar turned off.
The SBX failed during an flight test on January 31, 2010, designated FTG-06. The test was a simulation of a North Korean or Iranian missile launch. The failure arose from two factors, the first being that algorithms in the SBX radar software which are designed to filter out extraneous information from the target scene were left disengaged for the test, and the second was a mechanical failure in a thruster on the kill vehicle.
During flight test FTG-06a on December 15, 2010, the SBX performed as expected, but intercept of the target missile was again not achieved.
Operational history
The SBX deployed in 2006. The ship has spent time for maintenance and repair at Pearl Harbor, Hawaii several times, including 170 days in 2006, 63 days in in 2007, 63 days in 2008, 177 days in 2009, and 51 days in 2010. When not at Hawaii, the SBX has been on operational deployments in the Pacific, including traveling to waters off Alaska. The ship has not moored at Alaska, in spite of the construction of a $26 million, eight-point mooring chain system installed in 2007 in AdakAdak Island
Adak Island is an island near the western extent of the Andreanof Islands group of the Aleutian Islands in Alaska. Alaska's southernmost town, Adak, is located on the island...
's Kuluk Bay. On June 23, 2009, the SBX was moved to offshore Hawaii in response to a potential North Korean missile launch. Between 2009 and 2010, the platform spent 396 continuous days at sea. In May 2011 the SBX-1 entered Vigor Shipyard (formerly the Todd Pacific Shipyard) in Seattle for a $27 million upgrade and maintenance work by contractor Boeing.
External links
- Sea-Based X-Band Radar (SBX) Sourcebook, July 2007 (24M PDF) via Federation of American Scientists
- Sea-Based X-Band Radar (SBX) Sourcebook Volume II, via Federation of American Scientists
- Sea-Based Ballistic Missile Defense -- Background and Issues for Congress, Congressional Research Service, June 2007, via Federation of American Scientists
- United States Missile Defense Agency
- Boeing Multimedia Sea-Based X-band Radar Image Gallery
- Sea-Based X-Band Radar Arrives in Pearl Harbor, 2006-01-10
- – MDA announces arrival of SBX at Pearl Harbor, Hawaii (PDF)
- About Raytheon IDS