USCG seagoing buoy tender

The USCG seagoing buoy tender is a type of United States Coast Guard cutter originally designed to service aids to navigation throughout the waters of the United States, and wherever American shipping interests require. The U.S. Coast Guard has maintained a fleet of seagoing buoy tenders dating back to its origins in the U.S. Light House Service (USLHS). These ships originally were designated with the hull classification symbol WAGL, but in 1965 the designation was changed to WLB, which is still used today.

Two classes of the WLB cutters have been produced. The older class, the 180 ft-class cutters, were 180 feet (55 m) long. Thirty-nine of these vessels were built from 1942–1944. All but one were constructed in the shipyards of Duluth, Minnesota. The 180 fleet, many of which served for more than 50 years, all went through different mid-life modifications that essentially resulted in three different classes of ship. All of the 180s are now retired and have been replaced with the new 225-foot (69 m) Juniper-class cutters. The last 180-foot cutter, USCGC Acacia, was decommissioned on 7 June 2006.

The Jonquil class of 189-foot (58 m) buoy tenders were U.S Army built mine planters acquired by the Coast Guard after World War II. Built around 1942, these vessels were designed for diesel engines but low pressure steam plants were installed instead.

The new Juniper buoy tenders are designed and operated as multi-mission platforms. While the 180s also performed other Coast Guard missions, they lacked the speed, communications, navigation and maneuverability of the new Junipers. Today, the Junipers conduct almost as much law enforcement as aid to navigation work; they are also outfitted to handle oil spill recovery, search and rescue, homeland security, and some ice breaking operations.

Six U.S. Army Mine Planters built 1917—1919 were transferred to the U.S. Light House Service during a reduction in Army in the early 1920s. These, after absorption into the U.S. Coast Guard, became that service's "Speedwell class":

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