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Coast Guard District narrative histories 1945

59

59

BLACKOUT

"Blackout" entered the universal vocabulary with the advent of World War II, although, it had, in some degree, been used in all previous wars. The blacking out of municipal lights became the activity of the Civilian Defense Organization, but the problem of extinguishing lights on river and railroad bridges and the blacking out and silencing of navigational aids fell to the Coast Guard. Accordingly, The Commandant advised all Districts in October, 1940, that plans for the extinguishment of lighted aids and the silencing of sound signals were to be prepared in the event of a serious national emergency. In the 13th Naval District, a Board was immediately organized for the purpose of making a study of meeting any emergency which called for the purpose of interruption of the operation of navigational aids in the Seattle District, including all Canadian aids in the Strait of Juan de Fuca. The District Coast Guard Officer ordered this Board to study the Strategic areas of the Columbia River entrance, to study several bar harbor entrances, San Juan Islands and the Puget Sound Area, and to formulate a Blackout Plan. The Plan was submitted to the Commandant, 13th Naval District for approval, as the Coast Guard operated its blackout through the Senior Naval Officer of the District.

This Blackout Plan, as approved in September, 1941, divided the District into seven areas, designated as Blacks One to Seven, and each Black was further subdivided into seven sections indicated by letter so that any part of any area could be blacked out separately. The "S" Code, developed previously by Communications for exclusive use in this District, was enlarged to accommodate blackout activities in all communication between Coast Guard units. For example, if all aids in the District were to be blacked out, the "S" signal was "Signal 26"; if the lights were to be blacked out and the sound signals silenced, the "S" signal was "Signal 138". If a blackout was designated in Black One Area, the signal was "Signal 26-1A", etc. An "S" Code Signal Book was published for issuance to all units. Appropriate "S" signals were also prepared for the relighting of all aids.

Radiobeacons were not silenced under the general blackout but were covered by individual instructions to the Commanding Officers as required. Although an effort was made to cover all aids, it was understood that aids omitted or aids established after the Plan was distributed were to

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Last edit almost 3 years ago by Wjhoward
65

65

ANRAC

The enforcement of blackout in the United States at the outbreak of the war necessitated that, in addition to the blackout of municipal lights, the navigational aids in continental waters had also to be extinguished or silenced. (See blackout). To perform this action by manual labor consumed far too much valuable time and so it became expedient that a more swift method be devised. By 1942, Headquarters developed a radio control system for aids to navigation intended primarily for blacking out unattended lighted aids by means of radio signal. This system consisted of a control station transmitting specially coded ultra high frequency signals with a special receiver mounted on the buoys or other aids which responded to code signals and operated relays of gas valves to extinguish or relight gas lights or to turn off or on other types of aids. The system was designated by the coined word "RACAN" which was later changed to ANRAC to avoid confusion with RADAR beacons or RACONS.

The receiving control, in combination with an electric relay, was used to operate an electric bell signal to notify light keepers at outlying stations, lamplighters or buoy patrols that aids were to be extinguished. Such installations at certain visual vantage points permitted the person notified to observe the extinguishment procedure and to take the necessary action in those cases where receiving equipment proved faulty. This system of notification was considered as a means of relieving commercial communications facilities and was carefully planned in order to avoid serious results in case of testing operations. Weekly operational tests were made and all failures were reported in detail to Headquarters.

A transmitter and a keying unit were required for each control station, together with an emergency standby. A single control transmitter operated all receiving controls within its working radius of approximately 7 miles even though it was not within visual range of the receiving station. (The working radius of the control transmitter beyond its visual range depended on the size and nature of the obstruction; ordinary obstacles did not materially affect the working radius of a control transmitter.)

After a thorough study of the use of ANRAC, the District Coast Guard Officer, 13th Naval District, requested Headquarters' authority to install the equipment with Cape Disappointment Light Station as the control unit and the following buoys to be equipped with receivers:

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