What you see in these images is the PINE TREE LINE - the MID CANADA LINE - and the DEW LINE. The top two images also show the coastal defense and off shore warning systems.
The third image shows the DEW LINE in more detail. NOTE the triangle extending above the Dew Line on the right side. The top of the triangle is the Thule Greenland Air Force Base and the Nike Missile defense location.
To Defend and Deter
Science NORAD: DEFENSE OF A CONTINENT Monday, Nov. 25, 1957
ACROSS the North American continent from the edge of the polar icecap to the Mexican border lies a vast and wondrously intricate system of aerial defenses. A defense in depth, it was designed to-and will-limit to a minimum the breakthroughs of Soviet long-range bombers coming to pour nuclear destruction on the U.S.
The system that guards the North American continent today and is a hope for protection in the future includes: The 9,000-mile fence of the DEW (Distant Early Warning) line and its extensions, composed of air, sea and ground radar elements, circling the far approaches of the continent. A second warning system (the Mid-Canada line) of automatic and semiautomatic radar stations running across the wilderness of Central Canada. An intricate "interior zone" warning and control complex of offshore air and sea picket lines, continent-wide networks of radar stations, identification and interception centers, ground and air combat commands, from Labrador and British Columbia to Florida and Southern California.
Nerve center of the system is Ent Air Force Base in Colorado Springs, where some 700 Air Force, Army, Navy and Marine Corp officers and 1,500 enlisted men, along with about 40 Canadians, work in a precisely knit NORAD command. In a two-story, windowless operations center at Ent, a ganglion of more than 600 miles of electronic communications wire feeds information to markers of huge Plexiglas plotting boards, which show the air situation over every part of the continent at any given moment.
To carry out both functions without delay, NORAD must rely on the almost instantaneous coordination of all its parts, beginning with the outlying alarm bells of the newly completed, $600 million Arctic portion of the DEW line. Stretching for 3,000 miles along the northern rim of the continent, this line includes more than 50 stations whose surveillance radars interlock like an electric warning fan twelve miles high, from Alaska's Cape Lisburne to Canada's Baffin Island.
Dug in for their first winter of blizzards and long, lonely nights, 600 Americans and Canadians man the isolated DEW line stations, watching luminescent oscilloscopes in darkened rooms. Without the ability to intercept or even to defend themselves, they have a single mission: to detect penetration of the radar fence by unidentified aircraft.
Once this occurred, warning would be flashed southward within seconds through the system to the Alaskan Air Command in Anchorage or Pepperrell Air Force Base in Newfoundland, R.C.A.F. headquarters at St. Hubert near Montreal and NORAD at Colorado Springs. From there, over "hot line" red telephones, the alert would be relayed to SAC headquarters in Omaha and the Joint Chiefs of Staff in Washington for immediate consultation with President Eisenhower, whose decision to give SAC's bombers the "go ahead" could be made and dispatched within five minutes from the time the warning came from the DEW line.
Protecting the flanks of North America are DEW line extensions far out to sea, maintained by relays of radar-equipped Navy destroyer escorts and WV2 Super Constellations. These mid-ocean lines stretch from the Aleutians to the mid-Pacific and from Newfoundland to the mid-Atlantic. Backing them up will be chains of underwater "listening" lines, now being built parallel to the coasts, to detect and intercept missile-launching submarines several hundred miles out at sea. In addition, a ground DEW line extension is also under construction across the arc of the Aleutian Islands; other holes are plugged by the Alaskan Air Command, by SAC's own forward installations in Greenland and Iceland, and by AC&W (aircraft control and warning) stations along the northeastern Canadian coast.
Mid-Canada Line. With SAC bombers warned and on their way, electronically guided elements behind the DEW lines -interceptor fighters and guided missiles, already in place-would take on NORAD's second function, the interception and destruction of the attackers. Some 600 miles south of the Arctic DEW line, the mid-Canada line's double fence of warning stations would pick up the invaders, plotting information on course for their interception in the air north of settled areas. Aircraft control and warning stations of the Pinetree system along both sides of the U.S.-Canadian border would be brought into action, pinpointing the targets in the sky with their radar, and directing their destruction by antiaircraft fire, guided missiles or interceptor planes, now in the process of being armed with nuclear-warhead rockets. Behind the Pine-tree posts, watching for breakthroughs or for flank attacks from the sea, are a host of additional AC&W units, including lines of offshore picket ships, Air Force RC-121 Super Constellations, Navy ZPG-2W blimps and, in the Atlantic off Cape Cod, a Texas Tower (two others are under construction, off Nantucket and New Jersey).
Helping to speed interception are newly developed SAGE (SemiAutomatic Ground Environment) system units, now being installed at direction centers of Air Divisions into which Canada and the U.S. are divided for defensive action. Into SAGE computers will be fed information about aircraft anywhere within the Air Division's radar area. This information will instantaneously be translated into symbols on TV-like picture tubes, showing current air situations, and automatically calculating correct employment of defense weapons.
As air battle commanders watch the picture, they can direct interception by remote control, automatically ordering "scrambles" by interceptor planes at nearby bases, or fire from antiaircraft and Nike guided-missile batteries in the area. In either case, the interceptors or missiles will be steered to the targets by directions from SAGE. As the battle moves, information will be automatically transferred to computers and picture tubes in the adjacent Air Division area.
All of this deterrence to a manned bomber attack must have a raising of sights against missiles. Columbia University's Electronics Research Laboratories and the Air Force have developed a 3,000-mile, anti-missile radar-detection system, but huge appropriations and long months of testing are needed before it can be superimposed on NORAD's present defenses. Nike-Zeus and Wizard anti-missile missile systems, and an Air Force Special Weapons Center's proposal to use nuclear explosions as defense weapons against ICBMs in outer space, are similarly far from test stage.
The article below is followed by images that show the DEW Line, the MID Canada Line and the Pinetree Line. In addition to these radar picket lines facing north, the article speaks of the "flank" protection down the coastal lines.
The article does not mention, in name, the "Texas Towers" off the Alantic Coast. One of the images below does show an icon of a "Texas Tower". That icon is pointed out beside the image.
This icon is a "Texas Tower" Air Force radar picket station off shore.