Distant Early Warning Line: Wikis


Note: Many of our articles have direct quotes from sources you can cite, within the Wikipedia article! This article doesn't yet, but we're working on it! See more info or our list of citable articles.


From Wikipedia, the free encyclopedia

A rough map of the three warning lines. From north to south: Distant Early Warning (DEW) Line, Mid-Canada Line, and Pinetree Line.

The Distant Early Warning Line, also known as the DEW Line or Early Warning Line, was a system of radar stations in the far northern Arctic region of Canada, with additional stations along the North Coast and Aleutian Islands of Alaska, in addition to the Faroe Islands, Greenland, and Iceland. It was set up to detect incoming Soviet bombers during the Cold War, a task which quickly became outdated when intercontinental ballistic missiles became the main delivery system for nuclear weapons.

The DEW Line was the northernmost and most capable of three radar lines in Canada; the joint Canadian-US Pinetree Line ran from Newfoundland to Vancouver Island, and the Mid-Canada Line ran somewhat north of this.


Early history

Improvements in Soviet technology rendered the Pinetree Line and Mid-Canada Line inadequate and on February 15, 1954, the Canadian and American governments agreed to jointly build a third line of radar stations, this time running across the high Arctic. The line would run roughly along the 69th parallel north, 200 miles or 300 kilometers north of the Arctic Circle. The United States agreed to pay for the line, and employ Canadian labour. The majority of Canadian DEW Line stations were the responsibility of the Royal Canadian Air Force (Canadian Forces after 1968) although some manned facilities were jointly staffed with the U.S. Air Force.

The construction project employed more than 25,000 people. The line consisted of 63 stations stretching from Alaska to Baffin Island, covering almost 10,000 km. The locations were mapped out by John Anderson-Thompson[1] The project was finished in 1957. The following year, the line became a cornerstone of the new NORAD organization of joint continental air defence.


Map of Distant Early Warning (DEW) Line

There were three types of stations: small unmanned "gap fillers" that were checked by aircrews only every few months during the summer; intermediate stations with only a chief, a chef, and a mechanic; and larger stations that had a variable number of employees and may have had libraries, movie projectors, and other accommodations. The stations used a number of long-range pulse radar systems known as AN/FPS-19. The "gaps" between the stations were watched by the directional AN/FPS-23 Doppler radar systems, similar to those pioneered only a few years earlier on the Mid-Canada Line. The stations were interconnected by a series of radio communications systems, often relying on tropospheric scattering.

Quite quickly after its completion, the line lost much of its purpose. It was useless against ICBMs and submarine-launched attacks. A number of stations were decommissioned, but the bulk were retained to monitor potential Soviet air activities and to assert Canada's sovereignty in the Arctic.

In 1985, the more capable of the DEW Line stations were upgraded and merged with newly-built stations into the North Warning System. Automation was increased and a number of additional stations were closed. In 1990, with the end of the Cold War and collapse of the Soviet Union, the United States withdrew all their personnel and turned full operation of the Canadian stations over to Canada, while retaining responsibility for NWS Stations located in Alaska and Greenland.

Radar system

DEW line station at Point Lay, Alaska.
A DEW station in western Greenland is visible in the distance beyond the snow-drifted equipment pallets in the foreground of this photograph.

In Point Lay, Alaska, the main AN/FPS-19 search radar is in the dome, flanked by two AN/FRC-45 lateral communications dishes (or AN/FRC-102, depending on the date). To the left are the much larger southbound AN/FRC-101 communications dishes. Not visible is the AN/FPS-23 "gap filler" Doppler antenna.

The DEW Line was upgraded with fifteen new FPS-117 phased-array radars between 1985 and 1994, and re-named the North Warning System.[2]

Deactivation and clean-up

A controversy also developed between the United States and Canada over the cleanup of deactivated Canadian DEW Line sites. The stations had produced large amounts of hazardous waste that had been abandoned in the high Arctic. Especially damaging were the large quantities of PCBs. While the United States insisted that it was Canada's responsibility to clean up the sites they had managed, the Canadian government disagreed. In 1996, an agreement was reached that saw the United States contribute $100 million to the estimated $600 million cleanup effort.

Atlantic and Pacific Barrier

The DEW line was supplemented by two "barrier" forces in the Atlantic and the Pacific Oceans which were operated by the United States Navy from 1956 to 1965. These barrier forces consisted of five surface picket stations each manned by radar destroyer escorts and an air wing of Lockheed WV-2 Warning Star aircraft that patrolled the picket lines at 1,000-2,000 m (3,000-6,000 ft) altitude in 12- to 14-hour missions. Their objective was to extend early warning coverage against surprise Soviet bomber and missile attack as an extension of the DEW Line.[3]

An Atlantic barrier WV-2 and the radar picket destroyer escort USS Sellstrom (DER-255) off Newfoundland in 1957.

The Atlantic Barrier (BarLant) consisted of two rotating squadrons, one based at Naval Station Argentia, Newfoundland, to fly orbits to the Azores and back; and the other training at NAS Patuxent River, Maryland. BarLant began operations on 1 July 1956, and flew continuous coverage until early 1965, when the barrier was shifted to cover the approaches between Greenland, Iceland, and the United Kingdom (GIUK barrier). Aircraft from Argentia were staged through NAS Keflavik, Iceland, to extend coverage times.

The Pacific Barrier (BarPac) began operations with one squadron operating from NAS Barbers Point, Hawaii, and a forward refueling base at Naval Station Midway, on 1 July 1958. Its orbits overlapped the radar picket stations of the ships of Escort Squadron Seven (CORTRON SEVEN), from roughly Kodiak Island to Midway. Normally 4 or 5 WV-2s were required at any single time to provide coverage over the entire line.

Barrier Force operations were discontinued by September 1965 and their EC-121K (WV-2 before 1962) aircraft placed in storage.

See also


  1. ^ McGrath, T.: "The Commissioner’s Award for Public Service". The Canadian Surveyor, September 1975.
  2. ^ North American Radar - DEW Line Radar Update
  3. ^ Bouchard, Capt. Joseph F. (USN). "Guarding the Cold War Ramparts." dean-boys.com. Retrieved: 13 March 2009.

External links



Got something to say? Make a comment.
Your name
Your email address