WL Buoy Tenders
One mission of the U.S. Coast Guard (USCG) is to provide and service short range aids to navigation (ATON). ATON are used by mariners to navigate U.S. waterways in and around the continental U.S., Alaska, Hawaii, and U.S. territories, such as those in the Caribbean and the western Pacific. To service ATON, the USCG used a variety of resources ranging from four-person Aids to Navigation Teams to 55-person 180-foot seagoing buoy tender vessels. Federally owned ATON located throughout the U.S. waterway system fall into four categories: lighted buoys, unlighted buoys, lights, and day beacons. Buoy tenders perform four basic ATON services: aid inspection, battery recharge, mooring inspection, and buoy relief.
The U.S. Lighthouse Service [hereafter USLHS], one of the oldest agencies of the federal government at that time, merged with the U.S. Coast Guard under presidential order in 1939. Along with the Lighthouse Service bureaucracy and approximately 5,000 personnel came 39 lightships and a fleet of 64 vessels called lighthouse tenders.
Lighthouse Tenders were used for general duty which consisted mainly of servicing navigational aids and supplying necessities to lighthouses and lightships. In order to perform these duties the vessel must be able to carry personnel, cargo, fuel and water. In addition to the above, the vessel must have adequate deck space for working, storing and servicing buoys. In order to lift the buoys with their chains and sinkers, the vessels are equipped with derricks of a capacity commensurate with the size and duties of the vessel. In order that the buoys may be worked alongside, with reasonable safety to personnel, low freeboard is essential. The large tenders are equipped with booms approximately fifty feet long with a working capacity of twenty tons. The vessels are of medium speed, in general rather shoal draft, and are usually twin screw due to the draft limitation. The initial stability is of necessity quite high, due to the requirement of handling heavy weights over the side, coupled with a low freeboard requirement. The larger tenders are designed for open sea work, a smaller type being used for bays and sounds, and a still smaller type for protected waters. Vessels are powered with steam, diesel, and diesel-electric drives.
Each was manned by a full-time civilian crew of officers and men. Through years of service, including during times of war, these Lighthouse Service tenders and their crews had developed into a proud and professional maritime service. They were welcome additions to the Coast Guard and since that time, developing, building, laying, and tending maritime aids to navigation [hereafter ATON] has become a preeminent Coast Guard mission.
The Lighthouse Service constructed the majority of its tenders to work within specific geographic areas and each was therefore something of a "one-of-a-kind" vessel, although there were some standardized features built in to each of the larger tenders. But overall standardization was the wave of the future and the parsimonious Coast Guard accepted a tender design based generally on the 177-foot Juniper, modified it, and prepared to construct an entire fleet of tenders based on this single new design. With the clouds of war gathering on the horizon, national defense responsibilities became an important concern, as did the traditional duties of search and rescue [hereafter SAR] in addition to a tender's primary task of tending ATON. The final design was a highly versatile, single-screw vessel capable of tending ATON, conducting SAR operations, towing, carrying cargo, escorting convoys, fighting fires, conducting weather patrols, and limited icebreaking. In short, they were true Coast Guard cutters; vessels capable of carrying out the multitude of tasks assigned to the vessels of the nation's oldest sea-going service.
The Coast Guard continued with the Lighthouse Service's tradition of naming tenders after flora. During the war when the Coast Guard transferred to the U.S. Navy and adopted Navy classifications, the Coast Guard grouped all of the buoy tenders, be they sea-going, coastal, inland, river or construction tenders under the classification of "WAGL." By 1965, the service divided them by their area of operations and their capabilities. Thus the seagoing tenders were designated "WLBs" and those tenders that operated in coastal waters became "WLMs." These craft are the focus of this image gallery. The remaining types of tenders were classified as: river tenders were "WLRs," inland tenders became "WLIs," and inland construction tenders were designated "WLICs."
By the end of the Cold War there were 26 WLBs ser vicing approximately 4,450 ATON. WLBs are large, stable, heavy-lift vessels, and typically service the largest buoys in U.S. waterways located in the roughest waters, farthest from shore. The WLB is considered a multimission platform due to its endurance and offshore seakeeping capabilities. In the early 1990s, 59% of the underway time of the WLB fleet was devoted to servicing ATON and 27% is devoted to multi-mission activities, including enforcement of laws and treaties, search and rescue, ice breaking, and marine environmental response. The WLM class of coastal buoy tenders consists of 11 vessels servicing about 3,050 ATON. Since the WLM cannot withstand as severe an environment as the WLB, the aids it services are generally smaller, and it typically does not travel far offshore. The WLM is a focused mission vessel devoting about 88% of its underway hours to servicing ATON.
By the early 1990s the Coast Guard was in the process of acquiring new vessels to replace the capabilities of its aging seagoing and coastal buoy tender fleet. Thirty-two of the 37 buoy tenders in the two largest classes -- the seagoing buoy tenders, known as WLBs, and the coastal buoy tenders, known as WLMs -- were built in the 1940s and were beyond their design service lives. The remaining five tenders began reaching the end of their design service lives in 1995. Acquisition projects were underway for the design of the replacement WLBs (WLBRs) and replacement WLMs (WLMRs), with anticipated initial deliveries of these vessels in 1996. The replacement vessels will incorporate many improvements over the current vessels, including faster cruising speeds, automated chain in-haul systems, dynamic positioning systems, differential global positioning systems, and spilled oil recovery capabilities.
Compared to a WLMR, a WLBR can transit faster, carry more buoys on its deck, and stay at sea for longer periods of time. The WLBR's advantages, however, do not offset its greater cost and the relatively equal target ATON underway hours of the two platforms (1275 hours for the WLMR and 1260 hours for the WLBR). As a result, for every change in the baseline number of WLBRs there is a corresponding inverse change to the required number of WLMRs. The total number of ships required in the WLBR and WLMR fleet is a function of ATON requirements. The mix of WLBRs and WLMRs is driven by the WLBR baseline requirements.
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