47-foot Motor Lifeboat
Encyclopedia
The 47-foot MLB is the standard lifeboat
Lifeboat (rescue)
A rescue lifeboat is a boat rescue craft which is used to attend a vessel in distress, or its survivors, to rescue crewmen and passengers. It can be hand pulled, sail powered or powered by an engine...
of the United States Coast Guard
United States Coast Guard
The United States Coast Guard is a branch of the United States Armed Forces and one of the seven U.S. uniformed services. The Coast Guard is a maritime, military, multi-mission service unique among the military branches for having a maritime law enforcement mission and a federal regulatory agency...
(USCG). The 47′ MLB is the successor to the 44′ MLB.
The 47' MLB is designed to weather hurricane force winds and heavy seas, capable of surviving winds up to 50 knots (98 km/h), breaking surf up to 6 m and impacts up to three G's. If the boat should capsize
Capsize
Capsizing is an act of tipping over a boat or ship to disable it. The act of reversing a capsized vessel is called righting.If a capsized vessel has sufficient flotation to prevent sinking, it may recover on its own if the stability is such that it is not stable inverted...
, it self-rights in less than fifteen seconds with all equipment fully functional.
The boat's hull
Hull (watercraft)
A hull is the watertight body of a ship or boat. Above the hull is the superstructure and/or deckhouse, where present. The line where the hull meets the water surface is called the waterline.The structure of the hull varies depending on the vessel type...
and superstructure are constructed entirely from 5456 marine grade aluminum. Designed with a hard chined
Chine (boating)
A chine in boating refers to a sharp angle in the hull, as compared to the rounded bottoms of most traditional boat hulls. The term hard chine indicates an angle with little rounding, where a soft chine would be more rounded, but still involve the meeting of distinct planes. Chine log...
deep "V" planing hull
Planing (sailing)
Planing is the mode of operation for a waterborne craft in which its weight is predominantly supported by hydrodynamic lift, rather than hydrostatic lift .-History:...
, the 47' MLB exceeds its displacement speed. The frame is composed of 17 vertical bulkhead frames, each of which is welded to the deck and hull, and five of which are watertight.
Employing fly-by-wire control systems, the boat can be operated from four different locations: two from the enclosed bridge, and two amidships from an open bridge.
Situated less than 1 ft (30.5 cm) from the water line are recessed retrieval wells, allowing for easier recovery of persons and jetsam, and easier boardings. A watertight survivor's compartment is equipped for comprehensive first aid. It is situated at the combined center of rotation of the ship.
See also
- Cape class motor life boatCape class motor life boatThe Canadian Coast Guard maintains a fleet of Cape-class motor lifeboats, based on a motor lifeboat design used by the United States Coast Guard....
(the 47′ MLB in service with the Canadian Coast GuardCanadian Coast GuardThe Canadian Coast Guard is the coast guard of Canada. It is a federal agency responsible for providing maritime search and rescue , aids to navigation, marine pollution response, marine radio, and icebreaking...
) - Response boat-mediumResponse boat-mediumThe response boat-medium is a 45-foot utility boat used by the United States Coast Guard. It is intended as a replacement for the Coast Guard’s fleet of 41′ utility boats , which have been in use by the Coast Guard since the 1970s. The Coast Guard plans to acquire 180 of these RB-Ms over a 6–10...
- 44-foot motor lifeboat44-foot motor lifeboatThe 44-foot motor lifeboat was the standard workhorse of the United States Coast Guard rescue boat fleet. The 44′ MLB has been replaced by the 47′ MLB....
- 41-foot utility boat
External links
- US Coast Guard Datasheet on the 47 MLB
- Textron Marine contractor for the USCG 47 MLB
- MetalCraft Marine contractor for the CCG 47 MLB
- military.com