While the cold war played out between the United States and the Soviet Union, Fort William and Port Arthur sat at the centre of continental shipping and right beside North America's largest fresh water supply. Canada allied itself with other Western nations through organizations such as NATO (the North Atlantic Treaty Organization) and worked with the United States on military defences through NORAD (the North American Aerospace Defense Command).

Strategies were needed to keep Thunder Bay's citizens and other Canadians safe in the event of any type of nuclear attack. Throughout the 1960's, information was distributed in the form of pamphlets and books, describing ways to survive nuclear attacks, protect oneself from nuclear fallout, and how to obtain and organize proper emergency supplies. 

The Aircraft Detection Corps in the Lakehead

Image depicts text and plane diagram from; TBA 4231-02 Aircraft detection handbook diagram (2)

 Figure 1.                              Plate I



1. Navigation Light                         16. Pilot Tube (shows Air Speed)

2. Upper Wing                                  17. Leading Edge of Wing

3. Upper Aileron                              18. Lower Wing

4. Wing Center Section                  19. Machine Gun

5. Pilot's Cockpit                             20. Wheel Pants

6. Fuselage                                      21. Landing Gear Strut

7. Fin                                                 22. Wheels 

8. Rudder                                         23. Engine Cowling

9. Tail Light                                     24. Engine 

10. Elevator                                     25. Propeller Spinner

11. Stabilizer                                   26. Lower Wing

12. Tail Wheel                                 27. Center Section Strut

13. Stabilizer Strut                         28. Forward Wing Strut

14. Lower Aileron                           29. Upper Wing

15. Rear Wing Strut

The Parts of an Aircraft

[ 29 ]

World War II and Threats to the Lakehead

During World War II, the cities of Fort William and Port Arthur were the home of the Bombardier plane manufacturing plant. This meant they were threatened by enemy aircraft. The Royal Canadian Air force partnered with Bell Telephone Company and Canadian National Telegraph, set up air raid siren towers and observation posts to keep the cities safe.

In 1943, D.W. Ferrier, the General Traffic Manager for the R.C.A.F, contacted the Public Utilities Commission in Port Arthur to arrange an area of Port Arthur that the Aircraft Detection Corps (A.D.C.) would operate out of and the system in which they would  operate.  The A.D.C. was a group of mainly volunteer civilians whose job was to report on any enemy aircraft or vessels seen around the Lakehead during World War II.3 Observation posts were set up in strategic areas of Port Arthur and detection handbooks were given to observers to know how and when to send over reports to Fort William, then from there reported to Winnipeg for action.

Observation posts covered 124.3 kilometres and each separate one was identified by a specific code name, such as “Baffin 10”.5 The observers were all  given handbooks that would aid them in identifying potential threats, including information like aircraft markings and shapes, to the cities but these handbooks were also given to all the assisting telephone company offices so they could also make a report when needed.6

Along with having A.D.C. observers, Fort William and Port Arthur also served as distribution centres, receiving and sending calls in a radius of 141.6 kilometres.7 The Bell Telephone Company and Canadian National Telegraph would have connection points, at Kaministiquia, Sunshine, Shabaqua, Shebandowan, along with connections to Cameron Falls by radio.8 With the help of radio circuits ran by the Hydro-Electric Power Commission in Cameron Falls, long distance calls were also sent from Beardmore, Geraldton, and Long Lac, allowing more reports to be sent from Fort William to the Winnipeg regiments for documentation and action.9

Thirty-seven years after the set up of the Air Raid Sirens and about fifteen years after their last use, the siren located at the Fort William Gardens went off unexpectedly in 1980.10 This caused the Provincial Warning Officer to look into a testing system for the old alarms since they had worn down over the years and they were never to be heard unless there was an attack or radioactive fallout within the city. It was then decided that Canadian Forces Base Winnipeg and the 73rd Communication Group would test the sirens annually by using a growl test.11 Growl tests were done by starting up the engine of the siren, but not putting it to full power, resulting in the siren making a low humming noise to not worry the public.12 The sirens did accidentally go off every now and again, but only six to nine of the five hundred sirens in Ontario were estimated to go off every year.13 In result systems were put in the place to quickly shut off the engines if the sirens did start to wail.14


No major attack did ever hit the two cities, but the procedures that were put in place were ready to keep the Lakehead safe if there ever was a threat, and sometimes even if there wasn’t.


1. City of Thunder Bay Archives (TBA), Series 88, TBA 4231-02, “Air Raid Detection,”, 1943.
2. Ibid. (See Figure 4).
3. Ibid. (See Figure 4).
4. Ibid. (See Figure 2, 3, and 5).
5. City of Thunder Bay Archives (TBA), Series 88, TBA 4231-02. “Air Raid Detection,” Official Handbook for the Aircraft Detection Corps, September 1943.
6. Ibid. (See Figure 5).
7. City of Thunder Bay Archives (TBA), Series 88, TBA 4231-02, “Air Raid Detection,”, 1943. (See Figure 6)
8. Ibid. (See Figure 6).
9. Ibid.
10. City of Thunder Bay Archives (TBA), Series 117, TBA 5170-33, “Communications Telephone Service Air Raid Sirens,” 1980-1981. (See Figure 7).
11. Ibid. (See Figure 8). 
12. Ibid. 
13. Ibid. (See Figure 9).
14. Ibid. (See Figure 9).

Additional Images

Image depicts the wings and tail of a German aircraft with a label under the image saying "NATIONAL MARKINGS GERMAN AIRCRAFT". Label at the top describes the page as PLATE XI. Page number at the bottom is thirty-nine.


 Figure 2.                                   PLATE XI


Image depicts the wing and tail of a Russian aircraft with a label under the image saying "NATIONAL MARKINGS RUSSIAN AIRCRAFT". Label at the top describes the page as PLATE X and page number at the bottom is thirty-eight.

Image showing text from; TBA 4231-02 Air Commander Letter - Reduced

 National Markings 

German Aircraft

[ 39 ]














 Figure 3.                                   PLATE X


National Markings 

Russian Aircraft

[ 38 ]













 Figure 4.                 ROYAL CANADIAN AIR FORCE 



1.                     The Aircraft Detection corps of the Royal Canadian Air Force has been formed to provide prompt and reliable reports to our Defence Forces of the approach of hostile aircraft. Its personnel consists of volunteer civilian observers, who forward these reports through the normal communication facilities of the country.

2.                     Your company has patriotically granted the use of their facilities on a priority basis, to transmit these reports. However, the success of the plan depends on the speed and accuracy with which the reports are handled between the observer and the Defence Forces, and this link in the chain in the telephone operator. 


Image showing text from; TBA 4231-02 Bell Telephone Company Letter - Copy


Figure 5.     It was decided at that time that all "Aircraft Detection Corps" or "Army Flash" calls received at Port Arthur would be passed to Fort William for handling. Fort William, in turn, will route these calls to the Reporting Centre at Winnipeg, with the exception of calls received from Cameron Falls which will be routed to Sault Ste. Marie. In order that the Fort William operator will be able to recognize the calls from Cameron Falls, it was agreed that the Port Arthur operators would identify these calls in passing them to the Toll Centre. 

The decisions reached at Port Arthur have been incorporated in an Operating Practice, two copies of which are attached hereto. We are also sending a copy of this Practice to Mr. Mcdougall at Fort William, so that he can advise his operators what to expect on calls received from Port Arthur.

In addition to handling "Army Flash" calls from official observers, the R.C.A.F. have requested that telephone operators originate "Army Flash" calls themselves to report any matters which, in their judgement, should be reported and which, to their knowledge, have not already been reported by official observers. To assist them in rendering this help to the Aircraft Detection Corps, the R.C.A.F. are supplying each telephone office in the activated area a copy of the "Official Handbook for Aircraft Detection Corps", which was prepared for the use of their official observers. For your information, I am attaching a copy of this handbook, together with a letter from the Chief of Air Staff addressed to telephone operators. 

 Image showing text from; TBA 4231-02 Flying Officer Green Letter - Smaller CopyFigure 6. THAT after the recent incident concerning the siren alarm on the Fort William Gardens going off unexpectedly, it would seem appropriate to ask the City Clerk to investigate the channel and method of obtaining permission from the Federal Government to test the alarm sirens located throughout the City and to regularly do so with adequate public information being supplied as well. 


Image showing text from; TBA 4231-02 Flying Officer Green Letter - Smaller Copy

Figure 7. We confirm the suggested arrangement whereby Port Arthur and Fort William will be listed as distributing centres. In connection with warning centres contingent to Port Arthur, we beg to advise that we have long distance telephone points on the Canadian National Railways, a distance of approximately 88 miles west of Port Arthur, as follows: Sunshine, Kaministiquia, Shabaqua, Shebandowan, Kashabowie, and we expect later to have have long distance connection as far as Atikokan where the Steep Rock Mines will be located. These points are also accessible by Canadian National Telegraphs. 

We also have long distance connection to Cameron Falls, 88 miles east of Port Arthur on the Canadian National Railways. Cameron Falls is the location of the Hydro-Electric Power Commission's generating plants totalling 129,000 horsepower, with an invested capital of around ten million dollars and are the source of power supply for the entire Lakehead district including Port Arthur, Fort William and the mining centres around Beardmore, Geraldton, etc.

Image showing text from; TBA 5170-33 Deputy City Clerk ATTACK WARNING SIRENS- Copy

Figure 8. All of the sirens in Ontario are tested annually by teams from the nearest Military Base. The maintenance of the sirens in Thunder Bay are the responsibility of Canadian Forces Base Winnipeg and 73rd Communication Group. When a team is scheduled to go out in the field the Provincial Warning Officer (continues in Figure 9). 

Stamp in lower left reads: RECEIVED / Jan 29, 1981 / City of / Thunder Bay / City Clerks Dept.  

Image showing text from; TBA 5170-33 Deputy City Clerk ATTACK WARNING SIRENS page 2 Figure 9. is advised and he in turn then notifies the local radio stations and appropriate local authorities that siren testing will be carried out at a specified time and they are requested to advise the public of this fact. When audibly testing the sirens, they are given a growl test, that is they are started up to ensure the motor is working and shut down before they get up to speed. This is normally takes 3-5 seconds and the siren does not wail but rather gives a low tone that is not heard beyond the immediate vicinity.

Accidental soundings do unfortunately happen on occasion, caused by the environment, vandalism or line repair/maintenance, but then are the exception rather than the norm. Ontario which has in excess of 500 sirens average about 6-9 accidental soundings a year. We have effective procedures in place that can silence the offending siren in a relatively short period of time and get it back on line. 

I trust that this will satisfy your request, however if you require further information do not hesitate to contact me. 

Yours Truly / R. Lang / Major / Provincial Warning Officer




















































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