The Coast Guard
The Coast Guard continued with the experimentation and adoption of new buoy technology. In the early 1940s, the service conducted experiments with more specialized buoys intended to withstand swift currents and still remain highly visible.
Plastic Buoys
Plastic buoys were the subject of experimentation in the 1940s, the 1950s, and again in the late 1970s and early 1980s. Color tests in 1979 and '80 proved green-colored buoys were more visible than the traditional black can buoys.
Ensign Peaceful Atom
The Coast Guard embraced the promise of atomic power with the induction of its "Ensign Peaceful Atom." This buoy, and its cartoon personification, was touted by the media and the Coast Guard as the new wave in powering navigational aids. It was tested in Baltimore Harbor in 1961 and was quietly removed in 1966 after reports that the nuclear generator failed to keep the buoy lit. Later reports on the atomic buoy experiment admitted that it was a dismal failure.
Monster Buoys
In 1966, the Coast Guard began investigating the possibility of replacing lightships with Large Navigational Buoys or LNBs.Far from being a minor navigational aid, these so-called "monster buoys" have hulls up to 40 feet in diameter with a depth of up to 7 1¦2 feet. The LNB prototype, constructed in 1969, had a steel hull subdivided by six bulkheads. These more cost-effective LNBs, along with "Texas Towers," huge, permanent platforms, served as the death knell of lightships in the United States.
Modern Tenders
Tenders used by the Coast Guard are divided into seven distinct classes based upon the size and tending capacity.- Seagoing tenders are 180 feet long and are capable of lifting up to 20 tons. They are equipped for long voyages, and have ice-breaking bows for winter tending.
- The second group of tenders are the coastal tenders. They are 133 and 175 feet long and are characterized by their 10-ton lifting capacity and their high degree of maneuverability. The 157-foot class is equipped with twin controllable-pitch screws, twin rudders and bow thrusters as well as a 10-ton boom.
- Inland tenders are divided into two classes
- Large (100 to 131 feet) used primarily in the sheltered waters of bays and harbors. Along with their 10-ton capacity booms, they sometimes come equipped with a pile driver. This enables them to double as construction and repair vessels. Their hulls are also characterized by broad flat bottoms, which usually draw about 3 feet when fully loaded.
- Small tenders (65 to 91 feet) are the pusher-tenders so familiar along U.S. rivers. The pusher-tender combination is comprised of a "living vessel" and a working barge complete with boom and pile driver. It is also characterized by its spuds. The spuds, two to four large timbers not unlike telephone poles, drop down through slots in the barge. This holds the barge in place, and is an effective mooring system in sheltered waters.
- River tenders are flat-bottomed, shallow-draft vessels that draw between 3 to 9 feet of water and have a 10-ton boom capacity. Crews on these tenders range from nine to 25 people.They are also divided into two classes
- large (104 to 115 feet) and
- Small (65 to 75 feet)
CGC Juniper & Ida Lewis
The CGC Juniper is the first of a new class of seagoing tenders. The cutter is 225 feet long, 46 feet at the beam, and has a draft of 13 feet. Launched in July 1995 and due for commissioning in the spring of 1996, the Juniper, along with the Ida Lewis - the first of the "Keeper" class, represents the new wave in buoy tending.The Juniper's twin diesel engine propulsion system supplies the speed and maneuverability necessary to tend coastal buoys and offshore exposed location buoys. Perhaps the most important advancement is the use of a new Dynamic Positioning System. DPS uses the Differential Global Positioning System to fix a position. Using this technology, the crew of the Juniper will be able to maintain the vessel's position within a 10-meter circle in conditions including winds of up to 30 knots with waves up to 8 feet. When setting buoys with this new technology, the Juniper's margin of error should be near zero percent.
