Monday, September 7, 2009

Shades of Light



Lightships


From 1898 to 1971, lightships were important elements in the system of navigation aids along Washington’s coast. On May 22, 1898, Light Vessel No. 67 became the first on Washington’s coast. She arrived at Umatilla Reef, 11 miles south of Cape Flattery. In 1909, Light Vessel No. 93 became Washington’s second lightship by taking station on Swiftsure Bank, 14 miles northwest of Cape Flattery. Thus, Washington had two of the Pacific Coast’s five lightships. Today lightships survive only as museum exhibits.



From Cape Mendecino to Cape Flattery


Maritime traffic bound for or departing Washington’s Columbia River ports also made use of Oregon’s only lightship, which was stationed off the Columbia River Bar. This made the Columbia Bar in one sense a "Washington" station because Columbia Bar lightships frequently served as relief vessels at Umatilla Reef and Swiftsure Bank.


The United States Lighthouse Service, which operated the lightships, placed the remaining two Pacific Coast light vessels at the San Francisco Bar and at Blunt’s Reef north of San Francisco. The lightships in California, Oregon, and Washington complemented the service’s lighthouses on the Pacific Coast. In Washington, these were at Cape Disappointment, North Head, Willapa Bay, Grays Harbor, Destruction Island, and Cape Flattery. They completed a chain of coastal beacons that stretched from California’s Cape Mendocino to Washington’s Cape Flattery. The arcs of the principal lights overlapped except for three short intervals.



Origin and Purpose of Lightships


The first world’s lightship went into operation in 1732 at the Nore, a sandbank in the estuary of England’s Thames River. Thereafter, in locations needing navigation aids but where lighthouse construction proved impossible or exorbitantly expensive, authorities, often reluctantly, substituted lightships. Officials responsible for navigation aids soon learned to prefer lighthouses to the floating beacons. Lightships, they learned, cost more to operate and maintain, and storms could drive them off station.


Lightship locations were usually approaches to ports or bays, or the outer limits of off-lying dangers such as reefs. In addition to their adaptability to localities inappropriate for lighthouses, lightships had the advantage of providing light and fog signals for which vessels could steer directly without fear of running aground. Early United States Coast Pilots even encouraged ships to run close aboard lightships. But following this advice had its hazards. In United States waters, ships have rammed lightships more than 100 times. In five instances, the lightships sank.


The first lightship in American waters began operation on Chesapeake Bay in 1820. Between 1820 and 1983, when the Coast Guard decommissioned the last American lightship, 179 of the vessels entered American service. At the peak of the lightship era in 1909, 56 lightships were in United States service.



Characteristics and Capabilities


American experience with lightships by the end of the nineteenth century led to a uniform design. Standard features included a length of about 135 feet, flat bottoms, rounded bows, bilge keels intended to reduce rolling, mushroom anchors weighing up to 7,800 pounds, and decks designed to allow water runoff. Lantern galleries with primary and standby lights on double masts permitted the ships’ beacons to be constantly illuminated. Radios became standard equipment for offshore lightships after 1901.


In 1912 the Light House Service assigned to its lightships visual call signs based on the International Code of Signals. These call signals, displayed through signal flags, added to the ways in which mariners could identify particular lightships. Until the 1920s, daymarks or distinctive round hoops mounted to one or both mastheads further identified each lightship.


Radios permitted not only ship-to-shore and ship-to-ship communication. They also enabled lightships to ask immediately for help for themselves or other craft, transmit critical weather bulletins, and report if blown off station. The U.S. Navy first assigned two-letter radio call signs for lightships. Three- and four-letter call signs developed by the U.S. Bureau of Standards soon replaced them. After 1921, lightships began to broadcast radio beacons that mariners could use to plot their location relative to the lightship.


When the Coast Guard took over the duties of the Light House Service in 1939-1940, it assigned new visual and radio call signs to lightships. The same radio call and flag hoist identified each lightship station with a separate call sign and hoist used by light vessels when they were off station. No. 113’s radio and visual call sign from 1940 to 1968 at Swiftsure Bank was, for example, NMJA. Submarine bells went into regular use in 1906. Suspended beneath some light vessel to a depth of 25 to 35 feet and operated by compressed air, the bells exhibited distinctive tones audible to distances of 10 miles or more to ships equipped with appropriate listening devices. In 1891, the U.S. Light House Service introduced its first self-propelled lightships. Prior to 1923, steam engines were universal. After 1923, diesel and diesel-electric power gradually replaced steam plants.


Lightships usually had straw-colored or red hulls. Either side of the hull bore the station’s name painted in large letters. After 1940, the U.S. Coast Guard standardized its lightships’ paint schemes. Red hulls featured six-and-one-half-foot white letters announcing the light station’s name. White paint distinguished deckhouses and boats, and mast and trim were buff. The ships became known by the names of their stations.


On November 28, 1899, gale force winds broke the heavy chains linking No. 50 to her anchors and drove the helpless ship onto Cape Disappointment on the Washington side of the Columbia River entrance. Six months’ effort at hauling her off the beach came to naught. In June 1900, three contractors suggested moving No. 50 overland to Baker’s Bay. This cove on the north shore of the Columbia, just inside the river entrance, lay about 700 yards from the grounding site. After laying No. 50 up at Astoria in 1909, the Light House Service had her surveyed and condemned in 1915. The service then sold her at public auction for $1,667.99 on April 27, 1915. Subsequent owners used her as a freighter in Alaskan waters under the name of San Cosmo and Margaret until 1935.



Umatilla Reef Station


Umatilla Reef Lightship Station was located offshore from the small Indian village of Ozette, 11 miles south of Cape Flattery. About four miles seaward from Cape Alva, and 2.5 miles south of Umatilla Reef, the station aided mariners transiting the coast or making landfall after transoceanic voyages. In Washington, No. 83 (later WLV 508) found a final resting place as a museum ship at Seattle’s Northwest Seaport. She had spent time at all five Pacific Coast light stations between 1905 and 1960, when she concluded her career as a relief ship for the Thirteenth Coast Guard District in Seattle.


The end of the lightship era in America began when a 1957 study estimated the annual cost of a lightship station at $1.32 million and determined that each station required 1.32 vessels. Seeking to cut costs, the U.S. Coast Guard began to replace the lightships with either offshore light structures similar to oil platforms or the new Large Navigation Buoys (LNBs). The steel 60-ton LNBs with 35-foot tower masts topped with 35-foot radio beacon antenna replaced deepwater lightship stations. Radio circuits provided remote control of navigation aids on the buoys. These included lights, sound signals, and radio beacons.



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