Pinetree Line

A rough map of the three warning lines. From north to south: Distant Early Warning (DEW) Line, Mid-Canada Line, and 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 (after its creation), 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early detection of a Soviet bomber attack on North America, but before the early 1950s radar technology quickly became outdated and the line was in full operation only for a short time.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 Defence (PJBD), 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 (potentially) 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 (to offer coverage of major Canadian cities) 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 "classic" pulsed mode 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 Doppler radar stations somewhat further north, which would develop into the Mid-Canada Line, and just over a year after MCL, a more advanced system in the extreme north was built which would be known as the DEW Line.

The Pinetree stations were kept operational during this period, and most underwent modifications as a part of the deployment of SAGE. 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

Site Number	Name	Province	Location	Unit	Service	Activated	Inactivated
C-53	CFS Alsask	SK		44 Aircraft Control and Warning (later Radar) Squadron	RCAF	1953	1986
C-15	CFS Armstrong	ON		914th Aircraft Control and Warning Squadron 38 Aircraft Control and Warning (later Radar) Squadron	USAF RCAF	1952	1974
C-20	CFS Baldy Hughes	BC		918th Aircraft Control and Warning Squadron 54 Aircraft Control and Warning (later Radar) Squadron	USAF RCAF	1953	1988
C-102	CFS Barrington	NS	}	672d Aircraft Control and Warning Squadron 23 Aircraft Control and Warning (later Radar) Squadron	USAF RCAF	1957	1990
C-17	CFS Beausejour	MB		916th Aircraft Control and Warning Squadron 48 Aircraft Control and Warning (later Radar) Squadron	USAF RCAF	1953	1988
C-11	RCAF Beaverbank	NS		22 Aircraft Control and Warning (later Radar) Squadron	RCAF	1954	1964
C-21	RCAF Saskatoon Mountain CFS Beaverlodge	AB		919th Aircraft Control and Warning Squadron 57 Aircraft Control and Warning (later Radar) Squadron	USAF RCAF	1953	1988
N-28A	Cape Makkovik Air Station	NL		923d Aircraft Control and Warning Squadron	USAF	1957	1961
N-27	Cartwright Air Station	NL		922d Aircraft Control and Warning Squadron	USAF	1953	1968
C-42	CFS Chibougamau	QC		10 Aircraft Control and Warning (later Radar) Squadron	RCAF	1962	1988
C-36	CFB Cold Lake	AB		42 Aircraft Control and Warning (later Radar) Squadron	RCAF	1954	1991
C-35	CFB Comox	BC		51 Aircraft Control and Warning (later Radar) Squadron	RCAF	1954	1958
N-27A	Cut Throat Island Air Station	NL		922d Aircraft Control and Warning Squadron	USAF	1957	1961
C-52	CFS Dana	SK		45 Aircraft Control and Warning (later Radar) Squadron	RCAF	1964	1987
C-4	CFS Edgar	ON		31 Aircraft Control and Warning (later Radar) Squadron	RCAF	1953	1964
N-22B	Elliston Ridge Air Station	NL		642d Aircraft Control and Warning Squadron	USAF	1957	1961
C-9	CFS Falconbridge	ON		33 Aircraft Control and Warning (later Radar) Squadron	RCAF	1952	1986
N-27C	Fox Harbour Air Station	NL		922d Aircraft Control and Warning Squadron	USAF	1957	1961
C-3	CFS Foymount	ON		32 Aircraft Control and Warning (later Radar) Squadron	RCAF	1952	1974
N-31	Frobisher Bay AB	NU		926th Aircraft Control and Warning Squadron	USAF	1953	1961
N-25	CFB Gander	NL		226 Aircraft Control and Warning (later Radar) Squadron	RCAF	1953	1990
C-24	Goose Air Force Base	NL		Goose Air Defense Sector 64th Air Division 37th Air Division	USAF	1953	1971
C-49	CFS Gypsumville	MB		47 Aircraft Control and Warning (later Radar) Squadron	RCAF	1962	1987
C-18	CFS Holberg	BC		501 Aircraft Control and Warning (later Radar) Squadron 53 Radar Squadron	RCAF	1954	1991
N-28	Hopedale Air Station	NL	}	923d Aircraft Control and Warning Squadron	USAF	1953	1968
C-153	CFS Kamloops	BC		825th Aircraft Control and Warning Squadron 56 Aircraft Control and Warning (later Radar) Squadron	USAF RCAF	1957	1988
C-2	CFS Lac St. Denis	QC		11 Aircraft Control and Warning (later Radar) Squadron	RCAF	1952	1986
N-26B	La Scie Air Station	NL		921st Aircraft Control and Warning Squadron	USAF	1957	1961
C-119	CFS Lowther	ON		639th Aircraft Control and Warning Squadron 36 Aircraft Control and Warning (later Radar) Squadron	USAF RCAF	1957	1987
N-24	Melville Air Station	NL		107th Aircraft Control and Warning Squadron 641st Aircraft Control and Warning Squadron 641 Aircraft Control and Radar Squadron	USAF RCAF	1953	1988
C-33	CFS Moisie	QC		211 Aircraft Control and Warning (later Radar) Squadron	RCAF	1953	1988
C-1	CFS Mont Apica	QC		12 Aircraft Control and Warning (later Radar) Squadron	RCAF	1952	1990
C-44	CFS Moosonee	ON		15 Aircraft Control and Warning (later Radar) Squadron	RCAF	1961	1975
C-14	RCAF Station Pagwa	ON		913th Aircraft Control and Warning Squadron 37 Aircraft Control and Warning (later Radar) Squadron	USAF RCAF	1952	1966
C-7	RCAF Parent	QC		14 Aircraft Control and Warning (later Radar) Squadron	RCAF	1954	1964
C-54	CFS Penhold	AB		43 Aircraft Control and Warning (later Radar) Squadron	RCAF	1964	1986
C-19	RCAF Station Puntzi Mountain	BC		917th Aircraft Control and Warning Squadron 55 Aircraft Control and Warning (later Radar) Squadron	USAF RCAF	1952	1966
C-10	CFS Ramore	ON		912th Aircraft Control and Warning Squadron 35 Aircraft Control and Warning (later Radar) Squadron	USAF RCAF	1953	1974
N-30	CFS Resolution Island	NU		920th Aircraft Control and Warning Squadron	USAF	1951	1961
N-29	Saglek Air Station	NL		924th Aircraft Control and Warning Squadron	USAF	1953	1970
C-8	CFS Senneterre	QC		34 Aircraft Control and Warning (later Radar) Squadron	RCAF	1953	1988
C-16	CFS Sioux Lookout	ON		915th Aircraft Control and Warning Squadron 39 Aircraft Control and Warning (later Radar) Squadron	USAF RCAF	1953	1987
N-27B	Spotted Island Air Station	NL		922d Aircraft Control and Warning Squadron	USAF	1957	1961
N-26	Saint Anthony Air Station	NL		921st Aircraft Control and Warning Squadron	USAF	1953	1968
N-22	Red Cliff Air Station St. Johns Air Station	NL		642d Aircraft Control and Warning Squadron	USAF	1953	1961
C-5	CFS St. Margarets	NB		21 Aircraft Control and Warning (later Radar) Squadron	RCAF	1953	1988
C-6	RCAF St. Sylvestre	QC		206 Aircraft Control and Warning (later Radar) Squadron	RCAF	1955	1964
N-23	Stephenville Air Station	NL		105th Aircraft Control and Warning Squadron 640th Aircraft Control and Warning Squadron	USAF	1952	1971
C-34	CFS Sydney	NS		221 Aircraft Control and Warning (later Radar) Squadron	RCAF	1954	1991
C-36	RCAF Tofino	BC		52 Aircraft Control and Warning Squadron	RCAF	1955	1957
C-51	CFS Yorkton	SK		46 Aircraft Control and Warning (later Radar) Squadron	RCAF	1963	1986

See also

• List of Royal Canadian Air Force stations
• List of USAF Aerospace Defense Command General Surveillance Radar Stations

References

 This article incorporates public domain material from websites or documents of the Air Force Historical Research Agency.

• A Handbook of Aerospace Defense Organization 1946 – 1980, by Lloyd H. Cornett and Mildred W. Johnson, Office of History, Aerospace Defense Center, Peterson Air Force Base, Colorado
• The Pinetree Line
• Pinetree Line Database

External links

[http://www.trackingdistance.com 1997 video documentary by Greg Marshall - Personal stories from Canada's role in the Cold War and NORAD]