July 24, 1957 – Western Electric Builds the DEW Line

On this day in engineering history, Western Electric finished work on the first part of the Distant Early Warning (DEW) Line, a series of radar stations that were designed to detect incoming Soviet bombers armed with nuclear weapons. When the DEW Line was completed in 1961 with an eastern segment to Iceland, the New York Times called it "one of the modern wonders of the world".

North American Air Defenses

A joint project of the U.S. and Canadian governments, the DEW Line was an engineering marvel that pitted man against nature on the coldest battlefront of the Cold War. Built 200 miles above of the Arctic Circle and across the 69th parallel, DEW was the northernmost of three early-warning radar lines. The pulsed-radar Pinetree Line ran along Canada's 50th parallel while the Mid-Canada Line (MCL) or "McGill Fence" used Doppler-detection and spanned the 55th parallel.

Dog Sleds and Airlifts

As general contractor, Western Electric built the first part of the Distant Early Warning Line in just two short Artic summers. During the winter of 1954 - 1955, siting crews who traveled by snowmobiles and dog sleds identified the best locations for radar stations. According one historian, "Western Electric men wore 30 pounds of clothing and carried twenty-pound sleeping bags whenever going out for a stroll".

When the siting work was complete, Canadian subcontractors built the roads, docks, airfields and hangars needed for receiving and storing supplies in one of the most isolated parts of North America. In history's largest commercial airlift, 81 airlines delivered 120,300 tons in 45,000 flights in 32 months. Naval convoys that waited for warmer months delivered the majority of DEW Line supplies, however, transporting 281,600 of a total 460,000 tons.

Searching for Signs of Armageddon

The main DEW Line radar stations in Canada used the AN/FPS-19, a magnetron-type search radar built by Raytheon. With a peak power of 137 kW and a pulse repetition frequency of 400 Hz, the AN/FPS-19 was a high-power, L-band, search radar with two identical radar sets that fed a back-to-back antenna.

Auxiliary DEW Line radar stations used a Motorola-built Fluttar radar that operated at frequencies from 475 to 525 MHz. Designated as the AN/FPS-23, these Doppler-effect detection systems filled the low-altitude gaps between the AN/FPS-19 radars located at main stations. Both types of search radars served as a "tripwire" to alert DEW Line operators that an airborne intruder had passed through the transmit/receive path.

Decline of the DEW Line

Designed to detect Soviet bombers, the DEW Line declined in usefulness when North America's Cold War adversary developed intercontinental ballistic missiles (ICBMs) and submarine launched ballistic missiles (SLBMs). In 1985, the United States and Canada agreed to upgrade or replace (depending on one's perspective) the DEW Line with the North Warning System (NWC). Completed in 1992, the NWC includes ground-based stations and incorporates air warning and control aircraft (AWACs).

Resources:

http://en.wikipedia.org/wiki/DEW_Line

http://pubs.aina.ucalgary.ca/aina/DEWLineBib.pdf

http://www.porticus.org/bell/pdf/dewlinestats.pdf

http://www.lswilson.ca/mcl.htm

http://www.factscanada.ca/friday/friday-2000-07-10-06.shtml

http://www.lswilson.ca/dewline.htm