Lifeboat (shipboard)
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A lifeboat or liferaft is a small, rigid or inflatable
Inflatable lifeboats may be equipped with auto-inflation (
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
Origins
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
...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,
Titanic sinking
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the turn of the 20th century larger ships meant more people could travel, but safety rules regarding lifeboats remained out of date: for example,
It was not until after the sinking of
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.
World War II
During
In 1943 the US developed a
Totally enclosed lifeboat
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
Ships fitted with "free fall" lifeboats are an exception – they have only one boat, at the stern.[citation needed]
Equipment to be carried on lifeboats and liferafts
The Life Saving Appliance (LSA) requires that the following be provided;[6]
For lifeboats
- A complement of buoyant oars, sufficient to make headway in calm seas (except for free-fall lifeboats).
- Two boat hooks.
- A buoyant bailer and two buckets.
- A survival manual.
- Illuminated compass.
- Sea anchor.
- Two painters.
- Two hatchets (one at each end of the lifeboat).
- Watertight container with 3 liter of fresh water for each person the lifeboat is designed to hold.
- A rustproof dipper (with lanyard).
- A rustproof graduated drinking vessel.
- A food ration with an energy value of at least 10,000 kJ (2390 Calories) for each person the lifeboat is designed to hold, packed in airtight and waterproof packaging.
- Four red rocket parachute flares.
- Six red hand flares.
- Two buoyant orange smoke signals.
- One electric torch suitable for Morse signalling with spare batteries and bulb (in a waterproof container).
- One daylight signalling mirror.
- One copy of life saving signals on waterproof paper.
- One whistle or equivalent sound signal.
- One first aid kit in a resealable waterproof container.
- Anti-seasickness medication sufficient for each person for 48 hours.
- One jack knife attached by a lanyard.
- Three tin openers.
- Two rescue quoits with 30 meters of floating line.
- Manual pump suitable for bailing (if lifeboat not self bailing).
- One set of fishing tackle.
- Tools for adjustments.
- Fire extinguishing equipment suitable for liquid fires.
- A searchlight.
- A radar reflector.
- Thermal protective aids, two or for 10% of occupants, whichever is greater.
For liferafts
- One rescue quoit with 30 meters of floating line.
- One buoyant rescue knife with lanyard (two if liferaft holds more than 13 persons).
- One buoyant bailer (two if liferaft holds more than 13 persons).
- Two sponges.
- Two sea anchors.
- Two buoyant paddles.
- Three tin openers and a pair of scissors.
- One first aid kit in a resealable waterproof container.
- One whistle or equivalent sound signal.
- Four red rocket parachute flares.
- Six red hand flares.
- Two buoyant orange smoke signals.
- One electric torch suitable for Morse signalling with spare batteries and bulb (in a waterproof container).
- One radar reflector
- One daylight signalling mirror.
- One copy of life saving signals on waterproof paper.
- One set of fishing tackle.
- A food ration with an energy value of at least 10,000 kJ (2,400 Cal) for each person the liferaft is designed to hold, packed in airtight and waterproof packaging.
- Watertight container with 1.5 litres of fresh water for each person the liferaft is designed to hold. (0.5 litre per person may be replaced with desalination equipment).
- One graduated rustproof drinking vessel.
- Anti-seasickness medication sufficient for each person for 48 hours.
- Survival instructions.
- Immediate action instructions.
- Thermal protective aids, two or for 10% of occupants, whichever is greater.
Liferaft versus lifeboat
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
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]
-
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
Specialized lifeboats
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]
Vessels that house
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.
]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]
Transatlantic crossings
The first 19th-century shipboard lifeboat to make a transatlantic crossing was the
See also
- Airborne lifeboat
- Carley float
- Equipment of the United States Coast Guard
- Escape pod
- Lifeboat ethics - an ethical dilemma of resource distribution
- Lifeboats of the Titanic
- Marine evacuation system (MES)
- Poon Lim
- Royal National Lifeboat Institution
- Search and Rescue
- Steven Callahan
- Apollo XIII Lunar module
References
- ^ The Parliamentary debates (Authorized edition), Volume 200, 21 March 1870, p.323-324 H. M. Stationery Office, 1870
- ISBN 0813521971.
- ^ Corporation, Bonnier (1 April 1944). "Popular Science". Bonnier Corporation – via Google Books.
- ^ Magazines, Hearst (1 March 1943). "Popular Mechanics". Hearst Magazines – via Google Books.
- ^ McCall Pate (1918). The naval artificer's manual: (The naval artificer's handbook revised) text, questions and general information for deck. United States. Bureau of Reconstruction and Repair. p. 198.
- ^ "RESOLUTION MSC.48(66)" (PDF). International Maritime Organization. 4 June 1996. Archived from the original (PDF) on 2020-03-31. Retrieved 2020-05-14.
- ^ Riedmann, Meagan S. (October 19, 2010). "Portland company builds locally sourced life boats". The Working Waterfront. Archived from the original on 2014-03-24.
- SOLAS. May 2006. Retrieved 2007-02-27.[permanent dead link]
- ^ Self Propelled Hyperbaric Lifeboats, thrustm.com
- ^ "18". JOINT FLEET MAINTENANCE MANUAL - REV B. Vol. VI. United States Navy. Archived from the original on 2008-03-06. Retrieved 2009-05-08.
- ^ "Nautical archive, ship horn of the Red White & Blue". liveauctioneers.com. Live Auctioneers. 13 July 2019. Retrieved 19 September 2020.
- ISBN 9780071413060
External links
Media related to lifeboats at Wikimedia Commons
- "Luxury Liner" Life Raft For Bomber Crews At Sea April 1943 article, very detailed with drawings