7th Space Warning Squadron


The 7th Space Warning Squadron, Beale Air Force Base, Calif., guards the U.S. West Coast against sea-launched ballistic missiles. The unit is a geographically separated unit of Space Delta 4, Buckley Space Force Base, Colo. 

THE 7th SWS...

Operates the $780 million Upgraded Early Warning Radar charged with Missile Warning, Missile Defense and Space Domain Awareness missions.

Detects sea-launched or inter-continental ballistic missiles, characterizes the trajectory, and predicts the probable destination.

Reports detection information to the Missile Warning Center, located within Cheyenne Mountain Air Force Station, Colo. and Alternate Missile Warning Center at Offutt AFB, Neb.

Relays trajectory information to the Joint Functional Component Commander-Integrated Missile Defense operations Center for Ground-Based Midcourse Defense cueing.

Detects, characterizes, and relays information of satellites operating in low-Earth orbit to the 18th Space Defense Squadron located at Vandenberg SFB, Calif.


The 7th SWS is primarily responsible for detecting sea-launched ballistic missiles fired from submarines in the Pacific Ocean. The unit then determines how many missiles were launched and their probable destination, and reports that to the Missile Warning Center, located within Cheyenne Mountain AFS and Alternate Missile Warning Center at Offutt AFB. This unit helps form a two-layered, worldwide network of missile warning systems that also detects ICBMs within its field of view.

The 7th SWS's corollary mission of Missile Defense supports the Ground-Based Midcourse Defense element of the Ballistic Missile Defense System. This program's objective is the defense of the United States against a threat of a limited strategic ballistic missile attack. The Upgraded Early Warning Radar (UEWR) detects, acquires, and tracks inbound missiles to provide the necessary data to classify and engage the target. This target data allows the GMD Fire Control and Communications element to generate a weapons task plan, allowing for the engagement, interception, and negation of threat of a ballistic missile reentry vehicle in the exoatmospheric region of space.

In addition, the squadron tracks earth-orbiting satellites and reports the information to the 18th Space Defense Squadron located at Vandenberg SFB. This information is combined with information from other global sensors to maintain the Department of Defense’s satellite catalog.

The 18th Space Defense Squadron uses the catalog to keep track of more than 21,000 objects in orbit. The catalog is also used to generate the United Nations Registry Report, so national and international agencies can make sure new satellites will safely launch and orbit.

Speed is a key factor in day-to-day squadron activities. Within 60 seconds after detecting a launch, the crew on duty must determine if the detection is valid, under investigation, or anomalous due to computer, mechanical or personnel error. After that, the crew determines the number of launched vehicles and provides impact predictions on North America. Once the information is determined, the unit passes updates to the appropriate authorities. 


The UEWR uses nearly 3,600 small active antenna elements coordinated by two computers. One computer is on-line at all times, while the second automatically takes control if the first fails. The computers control the distribution of energy to the antennas to form precise patterns, allowing the radar to detect objects moving at a very high speed since no mechanical parts limit the radar sweep.

The radar can change its point of focus in milliseconds, while conventional radars may take up to a minute to mechanically swing from one area to another. The main building is shaped like a pyramid with a triangular base 105 feet on each side. The two radiating faces are tilted back 20 degrees. UEWR beams reach outward for nearly 3,000 nautical miles in a 240-degree sweep. At its extreme range, it can detect an object the size of a small car. Smaller objects can be detected at closer range.


The Air Force finished construction of the PAVE PAWS site at Beale in October 1979. It attained initial operational capability in August 1980. The unit was originally part of Aerospace Defense Command's 26th Aerospace Division.

In December 1979, it became part of Strategic Air Command.

The unit transferred to Air Force Space Command in May 1983, eventually becoming the 7th Missile Warning Squadron.

When the Air Force reorganized in 1992, the 21st Space Wing activated at Peterson AFB. The 7th MWS moved to the 21st SW and was renamed the 7th SWS.

In 2007, 7th SWS completed the upgrade to UEWR.

In December 2019, the United States Space Force was established creating the first new branch of the armed services in 73 years.

In July 2020, the 21st Space Wing was inactivated and 7 SWS was reorganized under Space Delta 4, Buckley SFB, Colo. to consolidate ground-based missile warning units with overhead persistent infrared units.

Beale AFB is located in north-central California, midway between San Francisco and Reno, Nev. The closest cities to the base are Marysville and Yuba City, Calif., about 10 miles to the west. Sacramento, the state capital, is 40 miles south of the base.