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 North American Aerospace Defense Command , over half were manned by United States Air Force personnel with the balance operated by the Royal Canadian Air Force. The line was the first coordinated system for early detection of a Soviet bomber attack on North America, but before the early 1950s radar technology quickly became outdated and the line was in full operation only for a short time.

History

Plans for what would become the Pinetree Line were underway as early as 1946 within the Permanent Joint Board on Defense, a Canadian-U.S. organization. However, the costs of running such a system in the post-war era was too high, and instead Canada concentrated on the areas around Ontario and Quebec, while the United States set up stations in the Midwest and along the eastern seaboard.
With the successful test of an atomic bomb in the USSR, plans changed considerably. In 1949 Congress agreed to a $161 million construction program in co-operation with the RCAF, for a continuous line of stations across southern Canada. The USAF's Continental Air Command and the RCAF met in October 1950 to start planning, and in January 1951 the PJBD presented Recommendation 51/1 for the Extension of the Continental Radar Defence System. The USAF later requested an additional set of six mobile stations to provide low-level coverage. It was later learned that the original radar systems performed better than expected, and a number of the mobile sites were never deployed.
The system was eventually deployed as a series of 33 main stations and 6 smaller "gap fillers". The majority of these ran in a line at about the 53rd parallel in the west and about the 50th parallel in the east. A second line ran up the eastern seaboard from the southern tip of Nova Scotia to the southern tip of Baffin Island. Of these, 22 of the main stations and all of the gap fillers were paid for by the USAF, leaving 11 to the RCAF. However 16 of the main stations were manned by RCAF personnel. On 1 January 1955, the system was officially handed over to RCAF command, and over time an additional 10 stations were added.
The Pinetree Line had several technical problems that limited its usefulness almost immediately. For one, the system used a pulse-Doppler radar, which made it unable to detect targets close to the ground due to "clutter". Another was that its location near population centres meant it offered only a "last minute" warning, and as the USSR moved to jet-powered bombers the warning time was falling. Studies were already underway in 1951 to build a much smaller series of much more capable Dopplar bistatic radar stations somewhat further north, which would develop into the Mid-Canada Line. By 1957, just over a year after the Mid-Canada Line was operational, a more advanced long-range search radar, mainly in the Canadian north and Alaska were deployed comprising the Distant Early Warning Line.
The Pinetree stations were kept operational during this period, and most underwent modifications as a part of the deployment of the Semi-Automatic Ground Environment. SAGE dramatically reduced the workload at the stations, cutting staff requirements by well over half. By the later 1950s some were being mothballed as newer systems came on line to the north. Nevertheless, many of the Pinetree stations were kept operational into the 1980s, particularly on the Atlantic and Pacific coasts.

Radar stations

Initial sort is based on longitude from east to west.
Site numberNameProvinceLocationUnitServiceActivatedDeactivated
N-22Red Cliff Air Station
St. Johns Air Station		NL 642d Aircraft Control and Warning SquadronUSAF19531961
N-22BElliston Ridge Air StationNL 642d Aircraft Control and Warning SquadronUSAF19571961
N-25CFB GanderNL 226 Aircraft Control and Warning SquadronRCAF19531990
N-26BLa Scie Air StationNL 921st Aircraft Control and Warning SquadronUSAF19571961
N-26Saint Anthony Air StationNL 921st Aircraft Control and Warning SquadronUSAF19531968
N-27CFox Harbour Air StationNL 922d Aircraft Control and Warning SquadronUSAF19571961
N-27BSpotted Island Air StationNL 922d Aircraft Control and Warning SquadronUSAF19571961
N-27Cartwright Air StationNL 922d Aircraft Control and Warning SquadronUSAF19531968
N-27ACut Throat Island Air StationNL 922d Aircraft Control and Warning SquadronUSAF19571961
N-23Stephenville Air StationNL 105th Aircraft Control and Warning Squadron
640th Aircraft Control and Warning Squadron		USAF19521971
N-28ACape Makkovik Air StationNL 923d Aircraft Control and Warning SquadronUSAF19571961
C-34CFS SydneyNS 221 Aircraft Control and Warning SquadronRCAF19541991
N-28Hopedale Air StationNL 923d Aircraft Control and Warning SquadronUSAF19531968
C-24Goose Air Force BaseNL Goose Air Defense Sector
64th Air Division
37th Air Division		USAF19531971
N-24Melville Air StationNL 107th Aircraft Control and Warning Squadron
641st Aircraft Control and Warning Squadron
641 Aircraft Control and Radar Squadron		USAF
RCAF		19531988
N-29CFS SaglekNL 924th Aircraft Control and Warning SquadronUSAF19531970
C-11RCAF BeaverbankNS 22 Aircraft Control and Warning SquadronRCAF19541964
N-30CFS Resolution IslandNT 920th Aircraft Control and Warning SquadronUSAF19511961
C-5CFS St. MargaretsNB 21 Aircraft Control and Warning SquadronRCAF19531988
C-102CFS BarringtonNS 672d Aircraft Control and Warning Squadron
23 Aircraft Control and Warning Squadron		USAF
RCAF		19571990
C-33CFS MoisieQC 211 Aircraft Control and Warning SquadronRCAF19531988
N-31Frobisher Bay Air BaseNT 926th Aircraft Control and Warning SquadronUSAF19531961
C-6RCAF St. SylvestreQC 13 Aircraft Control and Warning SquadronRCAF19551964
C-1CFS Mont ApicaQC 12 Aircraft Control and Warning SquadronRCAF19521990
C-2CFS Lac St. DenisQC 11 Aircraft Control and Warning SquadronRCAF19521986
C-42CFS ChibougamauQC 10 Aircraft Control and Warning SquadronRCAF19621988
C-7RCAF ParentQC 14 Aircraft Control and Warning SquadronRCAF19541964
C-8CFS SenneterreQC 34 Aircraft Control and Warning SquadronRCAF19531988
C-3CFS FoymountON 32 Aircraft Control and Warning SquadronRCAF19521974
C-4CFS EdgarON 31 Aircraft Control and Warning SquadronRCAF19531964
C-10CFS RamoreON 912th Aircraft Control and Warning Squadron
35 Aircraft Control and Warning Squadron		USAF
RCAF		19531974
C-44CFS MoosoneeON 15 Aircraft Control and Warning SquadronRCAF19611975
C-9CFS FalconbridgeON 33 Aircraft Control and Warning SquadronRCAF19521986
C-119CFS LowtherON 639th Aircraft Control and Warning Squadron
36 Aircraft Control and Warning Squadron		USAF
RCAF		19571987
C-14RCAF Station PagwaON 913th Aircraft Control and Warning Squadron
37 Aircraft Control and Warning Squadron		USAF
RCAF		19521966
C-15CFS ArmstrongON 914th Aircraft Control and Warning Squadron
38 Aircraft Control and Warning Squadron		USAF
RCAF		19521974
C-16CFS Sioux LookoutON 915th Aircraft Control and Warning Squadron
39 Aircraft Control and Warning Squadron		USAF
RCAF		19531987
C-17CFS BeausejourMB 916th Aircraft Control and Warning Squadron
48 Aircraft Control and Warning Squadron		USAF
RCAF		19531988
C-49CFS GypsumvilleMB 47 Aircraft Control and Warning SquadronRCAF19621987
C-51CFS YorktonSK 46 Aircraft Control and Warning SquadronRCAF19631986
C-52CFS DanaSK 45 Aircraft Control and Warning SquadronRCAF19641987
C-53CFS AlsaskSK 44 Aircraft Control and Warning SquadronRCAF19531986
C-36CFB Cold LakeAB 42 Aircraft Control and Warning SquadronRCAF19541991
C-54CFS PenholdAB 43 Aircraft Control and Warning SquadronRCAF19641986
C-21RCAF Saskatoon Mountain
CFS Beaverlodge		AB 919th Aircraft Control and Warning Squadron
57 Aircraft Control and Warning Squadron		USAF
RCAF		19531988
C-153CFS KamloopsBC 825th Aircraft Control and Warning Squadron
56 Aircraft Control and Warning Squadron		USAF
RCAF		19571988
C-20CFS Baldy HughesBC 918th Aircraft Control and Warning Squadron
54 Aircraft Control and Warning Squadron		USAF
RCAF		19531988
C-19RCAF Station Puntzi MountainBC 917th Aircraft Control and Warning Squadron
55 Aircraft Control and Warning Squadron		USAF
RCAF		19521966
C-35CFB ComoxBC 51 Aircraft Control and Warning SquadronRCAF19541958
C-36RCAF TofinoBC 52 Aircraft Control and Warning SquadronRCAF19551957
C-18CFS HolbergBC 501 Aircraft Control and Warning Squadron
53 Radar Squadron		RCAF19541991