Mid-Canada Line
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...
stations across the "middle" of Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
to provide early warning of a Soviet
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....
bomber
Bomber
A bomber is a military aircraft designed to attack ground and sea targets, by dropping bombs on them, or – in recent years – by launching cruise missiles at them.-Classifications of bombers:...
attack on North America. It was built to supplement the less-advanced Pinetree Line
Pinetree Line
The Pinetree Line was a series of radar stations located across the northern United States and southern Canada at about the 50th parallel north, along with a number of other stations located on the Atlantic and Pacific coasts. Run by NORAD , over half were manned by United States Air Force...
, which was located further south. The majority of Mid-Canada Line stations were used only briefly from the late 1950s to the mid-1960s, as the attack threat changed from bombers to ICBMs; the early warning role passed almost entirely to the more capable DEW Line further north.
Impetus
Construction of the Pinetree Line had only just started when air planners started to have concerns about its capabilities and siting. By the time it detected a potential attack by jetJet engine
A jet engine is a reaction engine that discharges a fast moving jet to generate thrust by jet propulsion and in accordance with Newton's laws of motion. This broad definition of jet engines includes turbojets, turbofans, rockets, ramjets, pulse jets...
-powered aircraft, there would be little time to do anything before the attack reached Canadian or northern U.S. cities. Additionally the Pinetree systems used "old" pulse-based radars that were fairly easy to jam and were unable to detect targets close to the ground due to scattering. Although expensive in terms of fuel use, it would be possible for Soviet bombers to evade detection by flying lower. They would eventually be seen as they approached the stations, but possibly so late that there would be no possibility of intercepting them. This made the Pinetree Line's usefulness somewhat suspect even before it had become operational.
Dr. W.B. Lewis, head of the AECL
Atomic Energy of Canada Limited
Atomic Energy of Canada Limited or AECL is a Canadian federal Crown corporation and Canada's largest nuclear science and technology laboratory...
Chalk River Laboratories
Chalk River Laboratories
The Chalk River Laboratories is a Canadian nuclear research facility located near Chalk River, about north-west of Ottawa in the province of Ontario.CRL is a site of major research and development to support and advance nuclear technology, in particular CANDU reactor...
and former Chief Superintendent of the UK Telecommunications Research Establishment
Telecommunications Research Establishment
The Telecommunications Research Establishment was the main United Kingdom research and development organization for radio navigation, radar, infra-red detection for heat seeking missiles, and related work for the Royal Air Force during World War II and the years that followed. The name was...
(TRE) had proposed to the Defence Research Board (DRB) a Doppler radar
Doppler radar
A Doppler radar is a specialized radar that makes use of the Doppler effect to produce velocity data about objects at a distance. It does this by beaming a microwave signal towards a desired target and listening for its reflection, then analyzing how the frequency of the returned signal has been...
system that avoided both of these problems. Known today as a "forward scatter bistatic radar
Bistatic radar
Bistatic radar is the name given to a radar system which comprises a transmitter and receiver which are separated by a distance that is comparable to the expected target distance. Conversely, a radar in which the transmitter and receiver are collocated is called a monostatic radar...
", it used two antennas, a transmitter and receiver, separated by about 60 km. Any aircraft flying between the antennas would be detected when it entered the beam and changed the received signal. Since the system relied on the speed of the aircraft to "shift" the frequency due to the Doppler effect
Doppler effect
The Doppler effect , named after Austrian physicist Christian Doppler who proposed it in 1842 in Prague, is the change in frequency of a wave for an observer moving relative to the source of the wave. It is commonly heard when a vehicle sounding a siren or horn approaches, passes, and recedes from...
, the radar could be aimed at static objects like the ground; although a signal would be reflected and received, since the ground is not moving this signal has no shift and can be easily filtered out.
Another advantage of the system is that it requires much less power to operate effectively. A conventional pulse radar spends most of its time turned off, listening for the reflections of its own signal. To ensure the reflections have enough energy to be detected, each pulse has to be extremely powerful. In a bistatic radar the signal is continually broadcasting and even tiny changes in the frequency can be seen and amplified, so a much smaller signal is needed. Compared to the existing Pinetree radars, Lewis' system would require much smaller sites and less power.
The major disadvantage of the system is that it did not indicate the aircraft's location within the beam, simply an indication of which beam had been "broken". Lewis proposed a system in which two overlapping lines of stations would be set up, forming a continuous "fence". This not only allowed one of the lines to cover the dead points directly over the antennas of the other, but also allowed for location within 30 km depending on which pair of beams were broken – a distance well within the detection ranges of interceptor aircraft
Interceptor aircraft
An interceptor aircraft is a type of fighter aircraft designed specifically to prevent missions of enemy aircraft, particularly bombers and reconnaissance aircraft. Interceptors generally rely on high speed and powerful armament in order to complete their mission as quickly as possible and set up...
radar. Lewis' design would be able to see any aircraft from ground level up to 65,000 ft.
Spider Web
The DRB decided to pursue Lewis’ idea in 1950-51 by directing a research contract to the Eaton Electronics Research Laboratories of McGill UniversityMcGill University
Mohammed Fathy is a public research university located in Montreal, Quebec, Canada. The university bears the name of James McGill, a prominent Montreal merchant from Glasgow, Scotland, whose bequest formed the beginning of the university...
, headed by Professor Garfield Woonton. Lewis suggested to DRB and Woonton that he put the project in the hands of Associate professor, Dr. J. Rennie Whitehead as project leader, working for the University on behalf of the Defence Research Board. Some preliminary tests were made in 1952 with 'breadboard' hardware, built by a graduate student, Hugh Hamilton, in order to confirm the validity of the idea.
In the meantime RCA Victor had been brought in by the DRB to design and produce the receivers, transmitters and antennae for tests on a substantial scale. The testing was performed in the summer of 1953, when Whitehead and his team of RCA Victor and RCAF personnel installed and operated a string of seven stations stretching from Ottawa
Ottawa
Ottawa is the capital of Canada, the second largest city in the Province of Ontario, and the fourth largest city in the country. The city is located on the south bank of the Ottawa River in the eastern portion of Southern Ontario...
to Mattawa
Mattawa, Ontario
Mattawa is a town in northeastern Ontario, Canada, at the confluence of the Mattawa and Ottawa Rivers in Nipissing District. Mattawa means "Meeting of the Waters" in Ojibwa...
along the Ottawa River
Ottawa River
The Ottawa River is a river in the Canadian provinces of Ontario and Quebec. For most of its length, it now defines the border between these two provinces.-Geography:...
valley. Known under the code name of "Spider Web", the tests were made with aircraft from Air Defence St. Hubert, near Montreal. All observations were transmitted to and made in the line HQ, which was set up in the equipment hut of one of the seven stations in Deep River
Deep River, Ontario
Deep River is a town in Renfrew County, Ontario, Canada. Located along the Ottawa River, it lies about north-west of Ottawa on the Trans-Canada Highway...
. Andrew Matthews of the 104 Communications Flight at RCAF St. Hubert arranged for a series of different aircraft to fly through the network, including an Auster
Auster
Auster Aircraft Limited was a British aircraft manufacturer from 1938 to 1961.-History:The company began in 1938 at the Britannia Works, Thurmaston near Leicester, England, as Taylorcraft Aeroplanes Limited, making light observation aircraft designed by the Taylorcraft Aircraft Corporation of...
light aircraft, a T-33 Shooting Star
T-33 Shooting Star
The Lockheed T-33 Shooting Star is an American-built jet trainer aircraft. It was produced by Lockheed and made its first flight in 1948, piloted by Tony LeVier. The T-33 was developed from the Lockheed P-80/F-80 starting as TP-80C/TF-80C in development, then designated T-33A. It was used by the...
, an Avro Lancaster
Avro Lancaster
The Avro Lancaster is a British four-engined Second World War heavy bomber made initially by Avro for the Royal Air Force . It first saw active service in 1942, and together with the Handley Page Halifax it was one of the main heavy bombers of the RAF, the RCAF, and squadrons from other...
bomber and even a recently acquired de Havilland Comet
De Havilland Comet
The de Havilland DH 106 Comet was the world's first commercial jet airliner to reach production. Developed and manufactured by de Havilland at the Hatfield, Hertfordshire, United Kingdom headquarters, it first flew in 1949 and was a landmark in aeronautical design...
jet transport. The tests revealed a great deal about the spectral ‘signatures’ of aircraft crossing the line at different points, and demonstrated the capability to detect all sizes of aircraft from 100 ft to over 40,000 ft in altitude. During this time Dr. Ross Warren of RCA Victor and Dr. Whitehead jointly developed the theoretical background for the work in a major report to DRB.
The Spider Web trials were followed in 1954 by intensive tests on a single link, built in the Eastern Townships
Eastern Townships
The Eastern Townships is a tourist region and a former administrative region in south-eastern Quebec, lying between the former seigneuries south of the Saint Lawrence River and the United States border. Its northern boundary roughly followed Logan's Line, the geologic boundary between the flat,...
for Bell who had by this time been given the go-ahead for the implementation of the Mid-Canada Line. The trials on this prototype link were also conducted by Whitehead and a small team in collaboration with Air Defence Command, St. Hubert, this time on behalf of Bell. The trials involved the flyover of numbers of B-52 bombers by arrangement with Strategic Air Command
Strategic Air Command
The Strategic Air Command was both a Major Command of the United States Air Force and a "specified command" of the United States Department of Defense. SAC was the operational establishment in charge of America's land-based strategic bomber aircraft and land-based intercontinental ballistic...
and a local bombplot unit. They also had full-time use of an Avro Lancaster
Avro Lancaster
The Avro Lancaster is a British four-engined Second World War heavy bomber made initially by Avro for the Royal Air Force . It first saw active service in 1942, and together with the Handley Page Halifax it was one of the main heavy bombers of the RAF, the RCAF, and squadrons from other...
from CFB Greenwood
CFB Greenwood
Canadian Forces Base Greenwood , commonly referred to as "14 Wing Greenwood" or CFB Greenwood, is a Canadian Forces Base located in Greenwood, Nova Scotia. It is primarily operated as an air force base by the Royal Canadian Air Force and is one of two bases in the country using the CP-140 Aurora...
for the important low-level tests. The senior uniformed member of the team, Flight Lieutenant Andy Matthews, arranged and navigated all the Spider Web and Eastern Township flight tests.
Deployment studies
In February 1953 the Canada-U.S. Military Study Group (MSG) was asked "to study those aspects of the North American Air Defence System in general, and the early warning system in particular, which are of mutual concern to the two countries." The MSG then asked the air defence commanders of Canada and the United States to prepare independent briefs on the subject. By July 1953, RCAF Air Defense Command had completed its brief, followed shortly thereafter by its USAF counterpart. Both reports suggested building a Doppler fence farther north, along the 55th parallel north55th parallel north
The 55th parallel north is a circle of latitude that is 55 degrees north of the Earth's equatorial plane. It crosses Europe, Asia, the Pacific Ocean, North America, and the Atlantic Ocean....
, roughly at the entrance of James Bay
James Bay
James Bay is a large body of water on the southern end of Hudson Bay in Canada. Both bodies of water extend from the Arctic Ocean. James Bay borders the provinces of Quebec and Ontario; islands within the bay are part of Nunavut...
into Hudson Bay
Hudson Bay
Hudson Bay , sometimes called Hudson's Bay, is a large body of saltwater in northeastern Canada. It drains a very large area, about , that includes parts of Ontario, Quebec, Saskatchewan, Alberta, most of Manitoba, southeastern Nunavut, as well as parts of North Dakota, South Dakota, Minnesota,...
.
In October 1953 the MSG recommended to both governments "that there be established at the earliest practicable date, an early warning line located generally along the 55th parallel between Alaska and Newfoundland", and outlined their minimum operational requirements. By the end of November 1953, the Mid-Canada Line had been approved in principle. Unlike the jointly-operated Pinetree line and future DEW line, the Mid-Canada line would be funded and operated entirely by the RCAF. The DRB estimated that the system would cost about $69,700,000, while an independent RCAF report placed it at $85,000,000.
In December an effort started to try to understand what sort of problems would be encountered during construction. Several "trains" consisting of tractor-pulled sleighs set out cross-country. One, manned by the RCAF, set out eastward from Fort Nelson, BC in order to link up with a second moving west from Flin Flon, Manitoba, while a third crewed by the Army left Lake Nipigon
Lake Nipigon
Lake Nipigon is the largest lake entirely within the boundaries of the Canadian province of Ontario . It is sometimes described as the sixth Great Lake. Lying 260 metres above sea level, the lake drains into the Nipigon River and thence into Nipigon Bay of Lake Superior...
near Thunder Bay
Thunder Bay
-In Canada:Thunder Bay is the name of three places in the province of Ontario, Canada along Lake Superior:*Thunder Bay District, Ontario, a district in Northwestern Ontario*Thunder Bay, a city in Thunder Bay District*Thunder Bay, Unorganized, Ontario...
, Ontario
Ontario
Ontario is a province of Canada, located in east-central Canada. It is Canada's most populous province and second largest in total area. It is home to the nation's most populous city, Toronto, and the nation's capital, Ottawa....
for Lansdown House about 200 km further north. The missions proved that it was possible to build the new line, but only during the winter when the muskeg
Muskeg
Muskeg is an acidic soil type common in Arctic and boreal areas, although it is found in other northern climates as well. Muskeg is approximately synonymous with bogland but muskeg is the standard term in Western Canada and Alaska, while 'bog' is common elsewhere. The term is of Cree origin, maskek...
was frozen solid. These missions also inspired the U.S. Army to invest in purpose-built overland train
Overland train
In the 1950s the LeTourneau company developed several overland trains, essentially oversized semi-trailer trucks that could travel over almost any terrain. Their intention was to be able to handle logistics needs without being dependent on local road or rail systems, allowing them to operate in...
s which they experimented with in the 1960s but never put into production.
While that was taking place, efforts were underway to start primary siting studies. It quickly became clear that the areas in question, at least in eastern Canada, were so remote that there was no really accurate topographical information. A huge effort to map the area in a 15-mile wide strip across the entire country was started by Transport Command almost immediately, and ended by the spring of 1954. With this information in hand a construction division was set up, the Systems Engineering Group (SEG), in February 1954, tasked with producing a final report on the system to be submitted on June 1.
Finalizing the plans
As the experiments continued it became clear that the radar stations could be located further apart, up to 90 km, reducing the number of stations required. Nevertheless the price rose, now estimated at about $120,000,000. Although their final report was not yet ready, the SEG put in an interim report in June and it was approved by cabinet by the end of the month.In their report they outlined the system that would be built almost exactly. It called for eight major Sector Control Centres, numbered from 200 to 900, each of which control up to thirty unmanned radar sites for a total of 90 radar stations. Each of the radar stations consisted of a single tall mast with a number of small dishes in fixed positions on top (typically four, two pointed in either direction), with power and electronics located in a building below the mast.
The sector control centres were linked using an advanced microwave
Microwave
Microwaves, a subset of radio waves, have wavelengths ranging from as long as one meter to as short as one millimeter, or equivalently, with frequencies between 300 MHz and 300 GHz. This broad definition includes both UHF and EHF , and various sources use different boundaries...
communications system developed in part by CADRE, which scattered off the troposphere
Troposphere
The troposphere is the lowest portion of Earth's atmosphere. It contains approximately 80% of the atmosphere's mass and 99% of its water vapor and aerosols....
for long-distance communications. The southernmost site along the eastern portion of the line, at Cape Henrietta Maria on Hudson Bay
Hudson Bay
Hudson Bay , sometimes called Hudson's Bay, is a large body of saltwater in northeastern Canada. It drains a very large area, about , that includes parts of Ontario, Quebec, Saskatchewan, Alberta, most of Manitoba, southeastern Nunavut, as well as parts of North Dakota, South Dakota, Minnesota,...
, was used as the main communications point, and three additional repeater stations transferred data from the line southward to the NORAD command center in North Bay, Ontario
North Bay, Ontario
North Bay is a city in Northeastern Ontario, Canada. It is the seat of Nipissing District, and takes its name from its position on the shore of Lake Nipissing.-History:...
. The easternmost station at Hopedale, Labrador
Hopedale, Newfoundland and Labrador
Hopedale is a town located in the North of Labrador, the mainland portion of the Canadian province of Newfoundland and Labrador. Hopedale is the legislative capital of the Inuit Land Claims Area Nunatsiavut, and where the Nunatsiavut Assembly meets...
was co-located with an existing Pinetree Line station in order to save construction costs.
All aircraft transiting the line would have to file a flight plan through the Mid Identification Zone, or MIDIZ, centred on the fence. The plans also called for the construction of several airbases known as Line Clearance Aerodromes just to the north of the line, where interceptor aircraft
Interceptor aircraft
An interceptor aircraft is a type of fighter aircraft designed specifically to prevent missions of enemy aircraft, particularly bombers and reconnaissance aircraft. Interceptors generally rely on high speed and powerful armament in order to complete their mission as quickly as possible and set up...
could operate in times of heightened alert.
At about this time another huge civil engineering
Civil engineering
Civil engineering is a professional engineering discipline that deals with the design, construction, and maintenance of the physical and naturally built environment, including works like roads, bridges, canals, dams, and buildings...
project was underway in Canada, the construction of a cross-Canada microwave relay telephone system. Since many of the logistics
Logistics
Logistics is the management of the flow of goods between the point of origin and the point of destination in order to meet the requirements of customers or corporations. Logistics involves the integration of information, transportation, inventory, warehousing, material handling, and packaging, and...
problems were similar, the construction group, led by Bell Canada
Bell Canada
Bell Canada is a major Canadian telecommunications company. Including its subsidiaries such as Bell Aliant, Northwestel, Télébec, and NorthernTel, it is the incumbent local exchange carrier for telephone and DSL Internet services in most of Canada east of Manitoba and in the northern territories,...
, was selected as a major contractor for the base construction. Detailed site selection started in 1955, with a major surveying effort running across Canada at the 55th parallel. The sites were so remote that the RCAF had to form up its first all-helicopter squadron in order to provide flight support for the survey teams.
Construction and service
Construction started in 1956 and proceeded quickly. By April 1957 the eastern half was operational, and the line was declared fully operational on January 1, 1958. Operations were shortly integrated into the newly-formed NORAD. Even the SEG's revised estimates turned out to be too low, and the fence's final cost is estimated at $224,566,830.It was not long before the RCAF started to have reservations about the costs of maintaining the Line. Although technically more capable than Pinetree, the MCL gave little information in terms of planning a response or vectoring interceptors to their targets, these tasks still required the Pinetree radars much further south. The extra time offered by the MCL was not considered worth the trouble of keeping the line operational. Even before the line became operational, in a repeat of earlier history, a new and more capable line was already under study that would combine the plotting capability of the Pinetree system with the line-breaking capabilities of the MCL, and located much further north to dramatically improve the detection and response times. Emerging as the Distant Early Warning Line
Distant Early Warning 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...
, or DEW, construction started before the MCL had become operational.
When the DEW line became operational in 1957 the value of the MCL was eroded, and the RCAF started pressing for it to be dismantled. The USAF disagreed, but the western half of the line was shut down in January 1964, leaving the eastern half to help defend the industrial areas of Canada and the US. However as the Soviet Union
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....
moved their offensive capability to ICBMs it became clear that both the MCL and Pinetree systems were of limited use, and the entire Mid-Canada line was shut down in April 1965.The operations site located at Cranberry Portage, Manitoba
Cranberry Portage, Manitoba
Cranberry Portage, located in the Rural Municipality of Kelsey, Manitoba, was an important part of the pre-European contact trade routes of the Cree and Assiniboine peoples...
, for example, has been converted into a high school and residence since active operations at the site closed in the mid-1960s.
Interestingly the MIDIZ remains administratively operational, although transit across it is not enforced.
External links
- The Mid-Canada Line: includes maps and photos from most of the stations