- Inflatable liferaft in hard-shelled canister
- Open inflatable liferaft
- Proactive lifeboat, sailing. Note unzipped middle section of canopy and reefed sail.
- Sea Watch 2, of Sea-Watch, picking up refugees adrift on liferafts
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A lifeboat or liferaft is a small, rigid or inflatable boat carried for emergency evacuation in the event of a disaster aboard a ship. Lifeboat drills are required by law on larger commercial ships. Rafts (liferafts) are also used. In the military, a lifeboat may double as a whaleboat, dinghy, or gig. The ship's tenders of cruise ships often double as lifeboats. Recreational sailors usually carry inflatable liferafts, though a few prefer small proactive lifeboats that are harder to sink and can be sailed to safety.
Inflatable lifeboats may be equipped with auto-inflation (carbon dioxide or nitrogen) canisters or mechanical pumps. A quick release and pressure release mechanism is fitted on ships so that the canister or pump automatically inflates the lifeboat, and the lifeboat breaks free of the sinking vessel. Commercial aircraft are also required to carry auto-inflating liferafts in case of an emergency water landing; offshore oil platforms also have liferafts.
Ship-launched lifeboats are lowered from davits on a ship's deck, and are hard to sink in normal circumstances. The cover serves as protection from sun, wind and rain, can be used to collect rainwater, and is normally made of a reflective or fluorescent material that is highly visible. Lifeboats have oars, flares and mirrors for signaling, first aid supplies, and food and water for several days. Some lifeboats are more capably equipped to permit self-rescue, with supplies such as a radio, an engine and sail, heater, navigational equipment, solar water stills, rainwater catchments and fishing equipment.
The International Convention for the Safety of Life at Sea (SOLAS) and the International Life-Saving Appliance Code (LSA) requires certain emergency equipment be carried on each lifeboat and liferaft used on international voyages. Modern lifeboats carry an Emergency Position-Indicating Radio Beacon (EPIRB) and either a radar reflector or Search and Rescue Transponder (SART).
During the Age of Sail, the ship's boats were used as lifeboats in case of emergency.
In March 1870, answering a question at the House of Commons of the United Kingdom about the sinking of PS Normandy, George Shaw-Lefevre said that
...in the opinion of the Board of Trade, it will not be possible to compel the passenger steamers running between England and France to have boats sufficient for the very numerous passengers they often carry. They would encumber the decks, and rather add to the danger than detract from it.
— George Shaw-Lefevre [1]
In the late 1880s, Maria Beasley improved the design of life rafts. She patented a life-saving raft in both the United States and England in 1880. [2]
By the turn of the 20th century larger ships meant more people could travel, but safety rules regarding lifeboats remained out of date: for example, British legislation concerning the number of lifeboats was based on the tonnage of a vessel and only encompassed vessels of "10,000 gross register tons (grt) and over".
It was not until after the sinking of RMS Titanic on April 15, 1912, that a broader movement began to require a sufficient number of lifeboats on passenger ships for all people on board. Titanic's gross tonnage of 46,000 tonnes was almost five times that which the Board of Trade lifeboat regulations were based on. Even though the 1,178 person capacity of its 20 lifeboats slightly exceeded the required 1,060, it still fell over 2,000 shy of the ship's maximum carrying load of 3,330 people.
The need for so many more lifeboats on the decks of passenger ships after 1912 led to the use of most of the deck space available even on the large ships, creating the problem of restricted passageways. This attempted to be addressed by creating (or adding) separate lifeboat decks, and the wider use of collapsible lifeboats,[ citation needed ] a number of which had been carried on Titanic.
During World War II and the Battle of the Atlantic with convoys going to northern Russia through the Arctic Ocean it was found that the chance of the crews of merchant ships surviving in open lifeboats was not very good unless they were rescued in a couple of hours. The US Navy asked various groups and manufacturers to suggest solutions. The result was the first enclosed, unsinkable, self-righting lifeboat, manufactured in Delanco, New Jersey; the first units were delivered in 1944. These radically new lifeboats were 24 feet (7.3 m) in length and weighed 5,000 lb (2,300 kg). They had two enclosed cabins (one at each end) which could hold a total of 25 persons. The space in between was designed to help persons in the water be pulled aboard, and could be enclosed with a canvas top. The new type lifeboat could be driven either by a small motor or sail. [3]
In 1943 the US developed a balsa wood liferaft that would not sink, irrespective of the number of holes (from enemy fire) in it. These balsa liferafts were designed to hold five to ten men on a platform suspended on the inside or fifteen to twenty-five hanging lines placed on the outsides. They were inexpensive, and during the war thousands were stored in any space possible on US warships and merchant ships. These liferafts were intended only for use during a short term before lifeboats or another ship in the convoy or group could bring them aboard. When USS Indianapolis, a cruiser operating alone, was sunk on 30 July 1945, none of its larger lifeboats were launched, and the survivors had to rely on balsa liferafts automatically released as the ship sank; many of the crew perished, but the balsa liferafts saved others; ultimately 316 of 1,196 crew survived. [4]
TEMPSC (Totally Enclosed Motor Propelled Survival Craft) are mandatory on all merchant vessels, tankers, MODUs, Floating Offshore Oil and Gas Platforms and some fixed offshore oil and gas platforms per 1983 Chapter III amendment to IMO SOLAS 1974. TEMPSC offer superior protection against fire on the water, poisonous gases and severe weather conditions (especially heat, cold and rough seas).[ citation needed ]
Merchant Vessels whose keels were laid on or before 1 January 1986 are required to have 200% evacuation capacity with one lifeboat fitted on the port side and one on the starboard side, so that a lifeboat is always available even if the ship is listing to one side. Lifeboat capacity is specified [5] and listed on the ship's "safety equipment certificate". Further details of the boats are found in "Form E" of this certificate.[ citation needed ]
Ships fitted with "free fall" lifeboats are an exception – they have only one boat, at the stern.[ citation needed ]
The Life Saving Appliance (LSA) requires that the following be provided; [6]
Liferafts in general are collapsible, and stored in a heavy-duty fiberglass canister, and also contain some high-pressure gas (in commercial models, usually compressed air) to allow automatic inflation to the operations size. SOLAS and military regulations require these to be sealed, never opened by the ship's crew; they are removed at set intervals (annually on merchant vessels) and sent to a certified facility to open and inspect the liferaft and contents. In contrast, a lifeboat is open, and regulations require a crew member to inspect it periodically and ensure all required equipment is present.[ citation needed ]
Modern lifeboats have a motor; liferafts usually do not. Large lifeboats use a davit or launching system (there might be multiple lifeboats on one), that requires a human to launch. Lifeboat launching takes longer and has higher risk of failure due to human factors. However lifeboats do not suffer from inflation system failures as inflatable liferafts do.[ citation needed ]
Since 2006 [7] smaller self-rescue lifeboats have been introduced for use by boats with fewer people aboard: these are rigid dinghies with carbon dioxide-inflated exposure canopies and other safety equipment. Like the lifeboats used before the advent of the petrol engine, these self-rescue dinghies are designed to let the passengers propel themselves to safety by sailing or rowing. In addition to their use as proactive lifeboats, these self-rescue dinghies are also designed to function as unsinkable yacht tenders.[ citation needed ] An example of a self-rescue dinghy/lifeboat is the Portland Pudgy.
The International Convention for the Safety of Life at Sea (SOLAS) makes it a requirement for merchant ships to have liferafts on each side of the ship, sufficient for all the people on board (the stated capacity of the lifeboat, irrespective of the fact that there may actually be fewer people on board). However, if the lifeboats are "easily transferable" (i.e. have an open deck between port and starboard lifeboat decks), the number of liferafts may be reduced to a total sufficient for the ship's capacity.[ clarification needed ]
The equipment carried in a liferaft is much less than a lifeboat. Unlike lifeboats, liferafts are not self-righting and have no motor.[ citation needed ]
Some ships have a freefall lifeboat stored on a downward sloping slipway normally on the stern of the vessel. These freefall lifeboats drop into the water when the holdback is released. Such lifeboats are considerably heavier as they are strongly constructed to survive the impact with water. Freefall lifeboats are used for their capability to launch nearly instantly, and high reliability in any conditions. Since 2006 they have been required [8] on bulk carriers that are in danger of sinking too rapidly for conventional lifeboats to be released. Seagoing oil rigs are also customarily equipped with this type of lifeboat.[ citation needed ]
Tankers are required to carry fireproof lifeboats, tested to survive a flaming oil or petroleum product spill from the tanker. Fire protection of such boats is provided by insulation and a sprinkler system which has a pipe system on top, through which water is pumped and sprayed to cool the surface while the boat is driven clear of the flames. This system, while not failsafe against engine failure, allows fireproof lifeboats to be built of fiberglass.[ citation needed ]
Vessels that house saturation divers carry hyperbaric lifeboats which incorporate a hyperbaric chamber to allow the divers to escape without undergoing decompression. [9]
In the United States, the United States Coast Guard ensures the proper type and number of lifeboats are in good repair on large ships.[ citation needed ]
The United States Navy (USN) uses five types of custom inflatable liferafts as well as a number of commercially available Coast Guard approved liferafts. The 25-person MK-6 and MK-7 are used on surface ships, the 50-person MK-8 on aircraft carriers and LRU-13A and LRU-12A on aircraft and submarines respectively. Smaller combatant craft often use 6, 10 or 15-person commercial liferafts. [10] The number of liferafts carried on USN ships is determined based on the maximum number of personnel carried aboard plus 10% as a safety margin. Aircraft carriers carry either 254 MK7 liferafts or 127 MK8 life rafts. While both are similar to heavy-duty commercial liferafts, USN liferafts use breathable air as the inflation gas rather than carbon dioxide to ensure full inflation within 30 seconds in Arctic environments.[ citation needed ]
Base material used on MK7 life rafts is polyurethane coated fabric which has very high durability. Old MK6 and a few MK8 life rafts are manufactured of neoprene-coated fabric, however, the majority of MK8 liferafts are also manufactured of polyurethane fabric. The lifeboat is compact and made of separate compartments, or "tubes", as a redundancy against puncture. Two air cylinders containing dry, breathable compressed air provide initial inflation. Depending on the model liferaft, each cylinder may contain up to 5000 psi of compressed air. Each liferaft is equipped with an external, automatically actuated light beacon and internal lighting. Power is provided by lithium batteries.[ citation needed ]
USN liferafts are stowed in heavy-duty fiberglass canisters and can be launched manually or automatically should the ship begin to sink. Automatic launching and inflation is actuated by a change in pressure sensed by a hydrostatic release device should the ship begin to sink. A hand pump is provided to "top-off" pressure at night when temperatures drop and internal air pressure decreases. Relief valves are installed in each tube to prevent overpressure. Repairs to holes or rips up to six inches in length can be made using special sealing clamps. Occupants in USN liferafts are protected from wind, rain and sun by built-in canopies which automatically inflate. Hatches are sealable to prevent rain and seawater from entering the liferafts. Survival equipment includes: manual reverse osmosis desalinator (MROD), bottles of fresh water, individual food packets, fishing kit, signaling mirror, rocket and smoke flares, flashlight, spare sea anchor, first aid kit, paddles, spare batteries and bulbs, and aluminized mylar sheets ("space blankets") to aid in caring for victims of hypothermia.[ citation needed ]
USN inflatable liferafts are serviced every five years. Each liferaft is test inflated before repacking. The USN liferafts have a high reliability rate of inflation.[ citation needed ]
The first 19th-century shipboard lifeboat to make a transatlantic crossing was the Red, White and Blue , which made the crossing in 38 days between New York City and Margate, England, with a two-man crew in 1866. [11] In 1870 the yawl City of Ragusa became the second small lifeboat to cross the Atlantic Ocean, from Cork to Boston with a two-man crew, John Charles Buckley and Nikola Primorac (di Costa). They upgraded it with two masts and took advantage of favorable winds on the return journey. [12]
A boat is a watercraft of a large range of types and sizes, but generally smaller than a ship, which is distinguished by its larger size or capacity, its shape, or its ability to carry boats.
A dinghy is a type of small boat, often carried or towed by a larger vessel for use as a tender. Utility dinghies are usually rowboats or have an outboard motor. Some are rigged for sailing but they differ from sailing dinghies, which are designed first and foremost for sailing. A dinghy's main use is for transfers from larger boats, especially when the larger boat cannot dock at a suitably-sized port or marina.
An inflatable boat is a lightweight boat constructed with its sides and bow made of flexible tubes containing pressurised gas. For smaller boats, the floor and hull are often flexible, while for boats longer than 3 metres (9.8 ft), the floor typically consists of three to five rigid plywood or aluminium sheets fixed between the tubes, but not joined rigidly together. Often the transom is rigid, providing a location and structure for mounting an outboard motor.
Capsizing or keeling over occurs when a boat or ship is rolled on its side or further by wave action, instability or wind force beyond the angle of positive static stability or it is upside down in the water. The act of recovering a vessel from a capsize is called righting. Capsize may result from broaching, knockdown, loss of stability due to cargo shifting or flooding, or in high speed boats, from turning too fast.
The International Convention for the Safety of Life at Sea (SOLAS) is an international maritime treaty which sets out minimum safety standards in the construction, equipment and operation of merchant ships. The International Maritime Organization convention requires signatory flag states to ensure that ships flagged by them comply with at least these standards.
A personal flotation device is a flotation device in the form of a vest or suit that is worn by a user to prevent the wearer from drowning in a body of water. The device will keep the wearer afloat with their head and mouth above the surface – they do not have to swim or tread water in order to stay afloat and can even be unconscious.
A davit is any of various crane-like devices used on a ship for supporting, raising, and lowering equipment such as boats and anchors.
Canoe diving and Kayak diving are recreational diving where the divers paddle to a diving site in a canoe or kayak carrying all their gear in or on the boat to the place they want to dive. Canoe or kayak diving gives the diver independence from dive boat operators, while allowing dives at sites which are too far to comfortably swim, but are sufficiently sheltered.
A survival suit, more accurately and currently referred to as an immersion suit, is a type of waterproof dry suit intended to protect the wearer from hypothermia if immersed in cold water or otherwise exposed after abandoning a vessel, especially in the open ocean. Immersion suits usually have integral footwear, and a hood, and either built-in gloves or watertight wrist seals. Suits manufactured by several manufacturers also include an inflatable pillow which is permanently attached high on the back, or an inflatable tube that is attached with zippers at two points on the chest, each side of the main zipper, and circles the back. When inflated, both of these devices provide enhanced stability to the wearer, which, if conscious, allows them to keep the head above water, and to keep wind and seas from striking the face. The inflation tube is routed from the inflatable pillow over the left shoulder of the user, and secured in a loop on the chest.
An able seaman (AB) is a seaman and member of the deck department of a merchant ship with more than two years' experience at sea and considered "well acquainted with his duty". An AB may work as a watchstander, a day worker, or a combination of these roles. Once a sufficient amount of sea time is acquired, then the AB can apply to take a series of courses/examinations to become certified as an officer.
An ordinary seaman (OS) is a member of the deck department of a ship. The position is an apprenticeship to become an able seaman, and has been for centuries. In modern times, an OS is required to work on a ship for a specific amount of time, gaining what is referred to as "sea time". For centuries, the term ordinary seaman was used to refer to a seaman with between one and two years' experience at sea, who showed enough seamanship to be so rated by their captain. Historically, in some navies and the merchant marine, a sailor with less experience was called a landsman.
A marine evacuation system (MES) is a lifesaving device found on many modern passenger ships or oil rigs consisting of an inflatable slide or escape chute where a passenger can evacuate straight into waiting life rafts. Developed in 1979 by RFD, a New Zealand–based company that distributes safety equipment; MES is replacing traditional davit-launched life rafts used on ships.
Steven Callahan is an American author, naval architect, inventor, and sailor. In 1981, he survived for 76 days adrift on the Atlantic Ocean in a liferaft. Callahan recounted his ordeal in the best-selling book Adrift: Seventy-six Days Lost at Sea (1986), which was on The New York Times best-seller list for more than 36 weeks.
The Carley float was a form of invertible liferaft designed by American inventor Horace Carley (1838–1918). Supplied mainly to warships, it saw widespread use in a number of navies during peacetime and both World Wars until superseded by more modern rigid or inflatable designs. Carley was awarded a patent in 1903 after establishing the Carley Life Float Company of Philadelphia.
The sinking of the Titanic resulted in the following changes in maritime policy: This includes an increase in life boats and life vests in case of emergency.
Airborne lifeboats were powered lifeboats that were made to be dropped by fixed-wing aircraft into water to aid in air-sea rescue operations. An airborne lifeboat was to be carried by a heavy bomber specially modified to handle the external load of the lifeboat. The airborne lifeboat was intended to be dropped by parachute to land within reach of the survivors of an accident on the ocean, specifically airmen survivors of an emergency water landing. Airborne lifeboats were used during World War II by the United Kingdom and on Dumbo rescue missions by the United States from 1943 until the mid-1950s.
The vessel MV Blythe Star was a coastal freighter which foundered off south-western Tasmania in October 1973. The crew of 10 successfully took to a small inflatable liferaft but drifted undiscovered. A search for the ship and its crew led to the largest maritime search operation conducted in Australia to that time.
Life-saving appliances are those appliances that protect human life at sea. The devices are documented as part of the International Convention for the Safety of Life at Sea, or SOLAS Convention.
MS Estonia sank on Wednesday, 28 September 1994, between about 00:50 and 01:50 (UTC+2) as the ship was crossing the Baltic Sea, en route from Tallinn, Estonia, to Stockholm, Sweden. The sinking was one of the worst maritime disasters of the 20th century. It is one of the deadliest peacetime sinkings of a European ship, after the Titanic in 1912 and the Empress of Ireland in 1914, and the deadliest peacetime shipwreck to have occurred in European waters, with 852 lives stated at the time as officially lost.
Submarine rescue is the process of locating a sunk submarine with survivors on board, and bringing the survivors to safety. This may be done by recovering the vessel to the surface first, or by transferring the trapped personnel to a rescue bell or deep-submergence rescue vehicle to bring them to the surface. Submarine rescue may be done at pressures between ambient at depth, and sea level atmospheric pressure, depending on the condition of the distressed vessel and the equipment used for the rescue. Self-rescue of submarine personnel by buoyant free ascent at ambient pressure is considered submarine escape. Survivors may require recompression treatment for decompression illness.
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