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Motor life boat

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The Motor Life Boat (MLB) is an integral part of a Coast Guard fleet, built to withstand the most severe conditions at sea. Designed to be self-bailing, self-righting and practically unsinkable, lifeboats are used as a heavy weather surf rescue response platform.

US Coast Guard Motor Life Boat CG-36535 off Nehalem River MLB Station, c. 1975
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US Coast Guard Motor Life Boat CG-36535 off Nehalem River MLB Station, c. 1975

The United States Coast Guard (USCG) and the British and Irish Royal National Lifeboat Institution (RNLI) have a long history with MLB's, from the early sail and oar driven lifeboats to the high speed modern MLBs introduced in the 1990s.

The sailors of the MLBs are called "surfmen", after the name given to the volunteers of the original United States Life Saving Service (USLSS).

Contents

Background

The first lifeboat is credited to Lionel Lukin, an Englishman who modified 20-foot Norwegian yawl in 1784 that was fitted with water-tight chambers filled with cork for additional buoyancy and a cast iron keel to make the boat self-righting.

These lifeboats were manned by 6 to 10 volunteers of organizations such as the USLSS and the RNLI who rowed out from shore when a ship was in distress and risked their lives in order to save the lives of the unfortunate souls on board.

A 2 cylinder 12 hp (9 kW) engine was fitted to a 34 foot (10 m) lifeboat in 1899 by Lake Shore Engine Company at the behest of the Marquette Life Saving Station on Lake Superior in Michigan. Its successful operation saw the introduction of the first Motor Life Boat and soon more and more lifeboat stations fitted their lifeboats with engines.

While provisions for sails and rowing would remain onboard, by 1909, 44 boats would be fitted with engines and power increased to 40 hp. The USLSS and the Revenue Cutter Service would merge in 1915 to form the United States Coast Guard as early predecessors of the 36 MLB would begin to take shape.

Early motor life boats

The 36 foot T model was introduced in 1929. At 36 ft 10 in length overall, 10 ft 9 in beam and with a 2 ton lead keel, she was powered by a 90 hp (67 kW) Sterling gas engine and had a speed of 9 knots (17 km/h). From the early days of the 20th century the 36 MLB was the mainstay of coastal rescue operations for over 30 years until the 44 MLB was introduced in 1962.
USCG MLB CG-44581
44 Motor Life Boat
First built: 1962
Last built: 1972
Number built: 110 by USCG, 52 under license
Builder: Coast Guard Yard, Curtis Bay, Baltimore, MD
General Characteristics
Displacement: 18,500 lb (8400 kg)
Length: 44 ft 1 in (13.4 m)
Beam: 12 ft 7 in (3.8 m)
Hull: Steel
Propulsion: Two 205 to 250 hp (153 to 186 kW) GM diesel engines
Speed: 15.5 knots (29 km/h)
Range: 190 nautical miles (350 km)
Righting capability: Rollover in under 30 seconds
Complement: 4 crew
Built at the Coast Guard Yard in Curtis Bay, Maryland, 218 36 T, TR and TRS MLB's were built between 1929 to 1956. Based on a hull design from the 1880s, the 36 TRS and her predecessors remain the longest active hull design in the Coast Guard, serving the Coast Guard and the Life Saving Services faithfully for almost 100 years, the last one, CG-36535, serving Depoe Bay MLB Station in Oregon until 1987.

The crews manning these boats typically had experience on local waters and had leadership from seasoned veterans whose boat handling skills were passed on directly to each new crewmember.

Localized training conducted at each unit allowed these crews to share their experiences and techniques. During the 1960s the Coast Guard replaced the 36-foot (11 m) MLB with the newly designed 44 foot (13 m) boat. These steel-hulled boats were more capable and more complicated than the wooden lifeboats they replaced.

While some coxswains resisted the new boat, holding on to their old 36s for as long as possible, claiming her canoe stern and aft cockpit to be favorable to the rounded stern and center helm station of the 44s, the 44 design is still in use today as many decommissioned models have been transferred to foreign maritime services.

Designed to return to an upright position in 30 seconds or less and with twin GM Diesel engines making 15 knots, she was bigger, faster and stronger than her wooden predecessors. Gold Lifesaving Medal recipient Boatswain's Mate First Class Bernie Webber who rescued 32 men from the tanker Pendleton with CG-36500 in 1952 had this to say about the 44 MLB in his book "Chatham: The Lifeboatmen":

"This new 44-footer was in sharp contrast to the old 36-footers like the CG36500. She was built of steel and powered by two GM diesel engines. She had two heated compartments for survivors, with settees and seat belts to hold them in safely during a rough passage. Unlike CG36500, which had only a compass for navigational equipment, the new 44-footer had an array of electronic aides. She was equipped with radar, direction finding equipment, depth finding equipment, and several radios with various range and frequencies. The boat had an enclosed pilot station, and a seat for the helm with a safety belt attached. It was also designed to roll over and come upright again."

Her range of stability was in excess of 175 degrees and rated for surf conditions up 20 feet (6 m), seas up to 30 feet (10 m) and winds up to 50 knots (93 km/h). Her crew of four could comfortably travel over 50 miles (80 km) offshore and tow vessels up to 125 gross tons.

In all 110 vessels would be built by the Coast Guard Yard in Curtis Bay between 1962 and 1972 with an additional 52 built by the RNLI, Canadian Coast Guard and others under license from the USCG.

Still in active service, the 44 MLB can be found in many third world countries and faithfully serving the Royal Volunteer Coastal Patrol in Australia, the Royal New Zealand Coastguard Federation, and even the US Coast Guard Station Chatham in Chatham, Massachusetts where CG44301 (the first production 44) is still in active service.

Modern motor life boats

A USCG 47 MLB
47 Motor Life Boat
First built: 1990 (prototype)
Last built: Still in Production
Number built: currently 117;
200 scheduled
Builder: Textron Marine
General Characteristics
Displacement: 40,000 lb (18,000 kg)
Length: 47 ft 11 in (15 m)
Beam: 14 ft (4.3 m)
Draft: 4 ft 6 in (1.4 m)
Hull: 5456 marine aluminium
Propulsion: Two 435 hp (324 kW) Detroit Diesel engines
Speed: 25 knots (46 km/h) max; 22 knots (41 km/h) cruise
Range: 200 nautical miles (370 km) cruise
Righting capability: Rollover in under 10 seconds
Complement: 4 crew, 5 passengers
The USCG has since designed and built new aluminum 47 foot lifeboats, with Textron Marine and Land Systems awarded the contract to design and build the US model, which was delivered in 1990. After 2 years of testing and evaluation, 5 more were built between 1992 and 1994 incorporating improvements from the prototype model for further testing and evaluation around the country. The first production boat was delivered to the USCG in 1997.

The 47 MLB is the most sophisticated MLB ever built, able to withstand impacts of three times the acceleration of gravity, she can survive a complete roll-over, self-righting in less than 10 seconds with all machinery remaining fully operational. Powered by twin Detroit Diesels producing 435 hp (324 kW) each, the 47 MLB can travel at 25 knots (46 km/h) to reach her destination.

There are currently 117 operational with a total of 200 scheduled to be delivered to the USCG. A further 27 models are being built by MetalCraft Marine under license to the Canadian Coast Guard.

In Britain, the RNLI design and build several types of all-weather motor lifeboats, the Arun class kept permanently afloat, the Tyne class slipway-launched boat and the Mersey class carriage-launched boat. More recently the Arun replacement Trent and Severn class prototype models were delivered in 1992 with the first production Trent arriving in 1994 and the Severn in 1996. The first production Tamar class, replacement for the Tyne went into service in December 2005 and the FCB2 class replacement for the Mersey is being developed for deployment in 2007.

References

Early Lifeboats 36 MLB 44 MLB 47 MLB Coast Guard Agencies Books

 

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