Distant Early Warning Line
From Wikipedia, the free encyclopedia
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 It was set up to detect incoming Soviet bombers during the Cold War, a task which quickly became outdated when intercontinental ballistic missiles became the main delivery system for nuclear weapons.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.
Contents |
[edit] 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, 200 miles or 300 kilometers north of the Arctic Circle. The Americans agreed to pay for the line, and employ Canadian labor. 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 over 25,000 people. The line consisted of sixty-three 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 and was considered an engineering marvel. The following year, the line became a cornerstone of the new NORAD organization of joint continental air defence.
[edit] Operations
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 distractions. 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.
[edit] Radar system
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]
[edit] 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.
[edit] See also
[edit] References
- ^ McGrath, T.: "The Commissioner’s Award for Public Service". The Canadian Surveyor, September 1975.
- ^ North American Radar - DEW Line Radar Update
[edit] External links
- The DEW Line sites in Canada, Alaska and Greenland
- DEW Line in Cambridge Bay
- yourYukon: Cleaning up the DEW Line
- Canadian content - dew line doo doo?
- FactsCanada - Feature
- Defence Construction Canada
- Royal Military College of Canada DEW Line Cleanup Project - Environmental Sciences Group
- Troposcatter communication network maps