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54-508: Rafiki may refer to: Cheeki Rafiki , English sailing yacht Rafiki, a mandrill in The Lion King Rafiki (film) , 2018 Kenyan film Rafiki Saïd (born 2000), Comorian footballer Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with the title Rafiki . If an internal link led you here, you may wish to change

108-571: A "light grounding": It is assumed that the structural damages in the hull of Cheeki Rafiki had not been sufficiently repaired after the previous groundings, such that the stability of the glued hull was compromised. It couldn't withstand the force of the increasing waves. The pictures show that the layers of the hull had separated. Some bolts could also have failed due to corrosion . The extensive report gives many recommendations for improvements. However, it does not ask for increased stability requirements for keel-to-hull constructions. Shortly after

162-500: A Doppler track is available. The COSPAS-SARSAT specifications say that a beacon location is not considered "resolved" unless at least two Doppler tracks match or a Doppler track confirms an encoded (GPS) track. One or more GPS tracks are not sufficient. An intermediate technology 406-MHz beacon (now mostly obsolete in favor of GPS-enabled units) has worldwide coverage, locates within 2 km (12.5 km search area), notifies kin and rescuers in 2 hours maximum (46 min average), and has

216-533: A GPS can only be localized to within 2 km (1.2 mi) by the COSPAS satellites and relied heavily upon the 121.5 MHz homing signal to pin-point the beacons location as they arrived on scene. The standard frequency of a modern EPIRB is 406 MHz. It is an internationally regulated mobile radiocommunication service that aids search-and-rescue operations to detect and locate distressed watercraft, aircraft , and people. The first form of these beacons

270-527: A beacon is about two hours. The first satellite constellation was launched in the early 1970s by the Soviet Union , Canada, France and the United States. Some geosynchronous satellites have beacon receivers. Since the end of 2003, there are four such geostationary satellites (GEOSAR) that cover more than 80% of the surface of the earth. As with all geosynchronous satellites, they are located above

324-425: A hex code. When the beacon is purchased, the hex code should be registered with the relevant national (or international) authority. After one of the mission control centers has detected the signal, this registration information is passed to the rescue coordination center, which then provides the appropriate search-and-rescue agency with crucial information, such as: Registration information allows SAR agencies to start

378-517: A model of international cooperation, even during the Cold War . SARSAT means search-and-rescue satellite-aided tracking. COSPAS ( КОСПАС ) is an acronym for the Russian words " COsmicheskaya Sistema Poiska Avariynyh Sudov " (Космическая Система Поиска Аварийных Судов), which translates to "space system for the search of vessels in distress". A consortium of USSR, the U.S., Canada, and France formed

432-800: A national police force, or a coast guard). These international search-and-rescue points of contact receive SAR alerts from the USMCC. The U.S. NOAA operates the U.S. Mission Control Center (USMCC) in Suitland, Maryland. It distributes beacon signal reports to one or more of these RCCs: (RCC Boston) (RCC Norfolk) (RCC Miami) (RCC New Orleans) (RCC Cleveland) (RCC Alameda and Pacific SAR Coordinator) (RCC Seattle) (RCC Honolulu; operated as JRCC with DOD) (RCC Juneau) (sub-sector of RCC Miami) The US Coast Guard web page for EPIRBs states: "You may be fined for false activation of an unregistered EPIRB. The US Coast Guard routinely refers cases involving

486-657: A precision of 100 m in the 70% of the world closest to the equator, and send a serial number so the responsible authority can look up phone numbers to notify the registrant (e.g., next-of-kin) in four minutes. The GPS system permits stationary, wide-view geosynchronous communications satellites to enhance the Doppler position received by low Earth orbit satellites. EPIRB beacons with built-in GPS are usually called GPIRBs, for GPS position-indicating radio beacon or global position-indicating radio beacon. However, rescue cannot begin until

540-575: A rescue effort. Cospas Sarsat Monitoring include: A transmission is typically detected and processed in this manner: Once the satellite data is received, less than a minute is needed to forward them to any signatory nation. The primary means of detection and location is by the COSPAS-SARSAT satellites. However, additional means of location are frequently used. For example, the FAA requires that all pilots monitor 121.500 MHz whenever possible, and

594-485: A rescue more quickly. For example, if a shipboard telephone number listed in the registration is unreachable, it could be assumed that a real distress event is occurring. Conversely, the information provides a quick and easy way for the SAR agencies to check and eliminate false alarms (potentially sparing the beacon's owner from significant false alert fines). An unregistered 406-MHz beacon still carries some information, such as

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648-472: A serial number to look up phone numbers, etc. This can take up to two hours because it has to use moving weather satellites to locate the beacon. To help locate the beacon, the beacon's frequency is controlled to 2 parts per billion, and its power is five watts. Both of the above types of beacons usually include an auxiliary 25-milliwatt beacon at 121.5 MHz to guide rescue aircraft. The oldest, cheapest beacons are aircraft ELTs that send an anonymous warble on

702-420: A ship sinking or medical emergency onboard, the transmitter is activated and begins transmitting a continuous 406 MHz distress radio signal, which is used by search-and-rescue teams to quickly locate the emergency and render aid. The signal is detected by satellites operated by an international consortium of rescue services, COSPAS-SARSAT , which can detect emergency beacons anywhere on Earth transmitting on

756-420: A suspended sentence whilst his bankrupt firm Stormforce was fined £ 50,000. Personal Locator Beacon An emergency position-indicating radiobeacon ( EPIRB ) is a type of emergency locator beacon for commercial and recreational boats, a portable, battery-powered radio transmitter used in emergencies to locate boaters in distress and in need of immediate rescue. In the event of an emergency, such as

810-682: A system with poor location detection abilities and long delays in detection of activated beacons. The satellite detection network was built after the ELT beacons were already in general use, with the first satellite not being launched until 1982, and even then, the satellites only provided detection, with location accuracy being roughly 20 km (12 mi). The technology was later expanded to cover use on vessels at sea (EPIRB), individual persons (PLB), and starting in 2016, maritime survivor locating devices (MSLD). All have migrated from using 121.500 MHz as their primary frequency to using 406 MHz, which

864-408: Is only accurate to 50 parts per million and the signals were broadcast using only 75–100 milliwatts of power. Coverage was partial because the satellite had to be in view of both the beacon and a ground station at the same time; the satellites did not store and forward the beacon's position. Coverage in polar and Southern Hemisphere areas was poor. False alarms were common, as the beacon transmitted on

918-538: The International Cospas-Sarsat Programme , the international satellite system for search and rescue (SAR). These beacons transmit a 406 MHz distress signal every 50 seconds, varying over a span of 2.5 seconds to avoid multiple beacons always transmitting at the same time. When manually activated, or automatically activated upon immersion or impact, such beacons send out a distress signal . The signals are monitored worldwide and

972-484: The USCG has a network of direction finder sites along the coastlines. The National Oceanic and Atmospheric Administration maintains a near-real-time map that shows SARSAT U.S. Rescues. Several systems are in use, with beacons of varying expense, different types of satellites, and varying performance. Carrying even the oldest systems provides an immense improvement in safety over carrying none. The types of satellites in

1026-561: The AIS location signal. The basic purpose of this system is to help rescuers find survivors within the so-called "golden day" (the first 24 hours following a traumatic event) during which the majority of survivors can usually be saved. The feature distinguishing a modern EPIRB, often called GPIRB, from other types of emergency beacon is that it contains a GPS receiver and broadcasts its position, usually accurate within 100 m (330 ft), to facilitate location. Previous emergency beacons without

1080-426: The accident. Furthermore, the crew could also not be blamed for the accident, because they were competent and the skipper was in the possession of all required certificates for such a voyage. At the time of the accident, the wind blew with force 7 , which is rough but still completely within the limits for which such boats are constructed. The accident investigation report points out though, that it's unclear whether

1134-431: The area in question, sent out a HC-130 Long Range Surveillance Aircraft. They were looking for a disabled yacht and persons in the water, since two PLB devices had sent emergency signals. The aircraft crew identified only debris at the expected position. On May 17, more than 24 hours after the last contact with the ship, the container vessel Maersk Kure identified Cheeki Rafiki ' s hull, upside-down. The keel

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1188-451: The aviation band distress frequency at 121.5 MHz. The frequency is often routinely monitored by commercial aircraft, but has not been monitored by satellite since Feb. 1, 2009. These distress signals could be detected by satellite over only 60% of the earth, required up to 6 hours for notification, located within 20 km (12 mi) (search area of 1200 km ), were anonymous, and could not be located well because their frequency

1242-401: The aviation emergency frequency, with interference from other electronic and electrical systems. To reduce false alarms, a beacon was confirmed by a second satellite pass , which could easily slow confirmation of a 'case' of distress to as much as 4 hours (although in rare circumstances, the satellites could be positioned such that immediate detection becomes possible.) The Cospas-Sarsat system

1296-505: The beacon and the orbit. If the beacon's frequency is more precise, it can be located more precisely, saving search time, so modern 406-MHz beacons are accurate to 2 parts per billion, giving a search area of only 2 km , compared to the older beacons accurate to 50 parts per million that had 200 km of search area. To increase the useful power, and handle multiple simultaneous beacons, modern 406-MHz beacons transmit in bursts, and remain silent for about 50 seconds. Russia developed

1350-435: The crew alive was in vain. The maximum time somebody can survive in water of 16 °C (61 °F) is about 15.5 hours. The accident resulted in heated discussion amongst yachtsmen over the safety of sailboats and particularly over the construction and dimensioning of the connection between keel and hull, which had obviously failed in this case, but is of utmost importance for a sailing vessel. There were speculations whether

1404-588: The customer in December 2006, who planned to enter her in charter regattas around Great Britain. In 2011, Stormforce Coaching took over the management of the yacht, but not her ownership. Subsequently, they entered the yacht twice into the Atlantic Rally for Cruisers (ARC), in 2011 and 2013. After each of these crossings, she stayed in the Caribbean Sea for a few months. The disaster happened during

1458-425: The distress frequency of 406 MHz. The satellites calculate the position or utilize the GPS coordinates of the beacon and quickly passes the information to the appropriate local first responder organization, which performs the search and rescue. As Search and Rescue approach the search areas, they use Direction Finding (DF) equipment to locate the beacon using the 121.5 MHz homing signal, or in newer EPIRBs,

1512-475: The equator. The GEOSAR satellites do not cover the polar caps. Since they see the Earth as a whole, they see the beacon immediately, but have no motion, and thus no Doppler frequency shift to locate it. However, if the beacon transmits GPS data, the geosynchronous satellites give nearly instantaneous response. Emergency beacons operating on 406 MHz transmit a unique 15-, 22-, or 30-character serial number called

1566-515: The hull. Many were broken and it had been like that for months. The yacht was therefore unsound, broken, and unsafe before the men left from Antigua." Innes pleaded not guilty . The jury at Winchester Crown Court acquitted Innes of manslaughter, but they did find him and the company guilty of unsafe operation of the vessel and of failing to fulfill the requirements of the Merchant Shipping Act . On May 11, 2018 Innes received

1620-400: The journey home in early 2014. Central to the later investigation was the construction of the hull and especially the link between the hull and the so-called "matrix", an inner layer that was embedded in the lower part of the hull to give it the necessary stability and stiffness. The keel was secured to the hull by ten bolts; nine of them 24mm in diameter and one 14mm. They were laminated into

1674-513: The keel actually separated, even though technically, computationally and based on the weather at the place of incident there was no obvious reason for this. The wreck of the Cheeki Rafiki was not available for investigation, as it has not been found yet. So the MAIB had to find their conclusions from the few pictures of the rescue crews, the history of the boat and reports from sister ships. It

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1728-586: The keel, and put through the outer hull, the matrix, and a steel washer , and then secured with nuts. The building process and the construction fulfilled the CE-seaworthiness Classification of category A (ocean), in the version valid at the time of building. Additionally, the construction process had been surveyed by Bureau Veritas . Cheeki Rafiki had participated in the Antigua Sailing Week event in spring 2014 and

1782-643: The link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Rafiki&oldid=1252282148 " Category : Disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages Cheeki Rafiki Cheeki Rafiki was a Bénéteau First 40.7, which had been built 2006 in Bénéteau's shipyard in Saint-Hilaire-de-Riez , France. She had been delivered to

1836-483: The location of the distress is detected by non- geostationary satellites using the Doppler effect for trilateration , and in more recent EPIRBs, also by GPS . Loosely related devices, including search and rescue transponders (SART), AIS-SART , avalanche transceivers , and RECCO do not operate on 406 MHz, thus are covered in separate articles. Cospas-Sarsat is an international organization that has been

1890-574: The manufacturer and serial number of the beacon, and in some cases, an MMSI or aircraft tail number / ICAO 24-bit address . Despite the clear benefits of registration, an unregistered 406-MHz beacon is very substantially better than a 121.5-MHz beacon, because the hex code received from a 406-MHz beacon confirms the authenticity of the signal as a real distress signal. Beacons operating on 121.5 MHz and 243.0 MHz only simply transmit an anonymous siren tone, thus carry no position or identity information to SAR agencies. Such beacons now rely solely on

1944-439: The manufacturer to remove the keel completely was considered best practice, its cost-effectiveness was questioned though. The report concludes that the most probable cause for the accident was a failure of the glued link between the "matrix" (inner skeleton) and the outer hull. Similar damages could be observed in sister ships which were involved in groundings, too. Different repair yards said that they could only hardly determine

1998-500: The network are: When one of the COSPAS-SARSAT satellites detects a beacon, the detection is passed to one of the program's roughly 30 Mission Control Centers , such as USMCC (in Suitland, Maryland), where the detected location and beacon details are used to determine to which rescue coordination centre (for example, the U.S. Coast Guard's PACAREA RCC, in Alameda, California) to pass the alert. The 406-MHz beacons with GPS track with

2052-435: The organization in 1982. Since then, 29 other countries have joined. The satellites used in the system include: Cospas-Sarsat defines standards for beacons, auxiliary equipment to be mounted on conforming weather and communication satellites, ground stations, and communications methods. The satellites communicate the beacon data to their ground stations, which forward it to main control centers of each nation that can initiate

2106-417: The original system, and its success drove the desire to develop the improved 406-MHz system. The original system was a brilliant adaptation to the low-quality beacons, originally designed to aid air searches. It used just a simple, lightweight transponder on the satellite, with no digital recorders or other complexities. Ground stations listened to each satellite as long as it was above the horizon. Doppler shift

2160-418: The path of the satellite in space and the rotation of the earth. This triangulates the position of the beacon. A faster change in the Doppler indicates that the beacon is closer to the satellite's orbit . If the beacon is moving toward or away from the satellite track due to the Earth's rotation, it is on one side or other of the satellite's path. Doppler shift is zero at the closest point of approach between

2214-542: The report was published operating company Stormforce and its director Douglas Innes were charged, with Innes facing four counts of manslaughter by gross negligence . He was accused of insufficient maintenance to cut costs. The yacht was, according to the Crown Prosecution Service , not seaworthy for an ocean passage, as several bolts of the keel were corroded or broken even before the voyage: "A number of keel bolts had broken, causing it to detach from

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2268-514: The second satellite pass almost doubled the average time before notification of the rescuing authority. However, the notification time was much less than a day. Receivers are auxiliary systems mounted on several types of satellites. This substantially reduces the program's cost. The weather satellites that carry the SARSAT receivers are in "ball of yarn" orbits, inclined at 99 degrees. The longest period that all satellites can be out of line-of-sight of

2322-413: The severity of such damages. Also, a skipper cannot easily determine whether a "light" grounding had caused any damage. The report states that "Almost all [yacht owners and professional yacht skippers asked] agreed that groundings can occur when racing, and that if, in their opinion, it was a ‘light’ grounding, no inspection for damage was necessary", while at the same time, there are several definitions for

2376-567: The ship was even allowed to set to sea under applicable laws. This because, as a professionally skippered boat, there are extensive rules concerning equipment, crewing and yearly safety inspections. The latter was overdue, but the operator was intending to postpone the inspection until the boat was back in England, so that he could avoid the costs of having to fly an inspector to the Caribbean . The investigation report then tries to evaluate why

2430-513: The shipyard had fallen below the margins for required hull stability to cut costs as a measure to win customers in the highly competitive market for affordable yachts. The report of the British Marine Accident Investigation Branch showed that the construction did satisfy the relevant construction specifications available at the time of construction. It even almost passed the revised ones at the time of

2484-616: The terrestrial or aeronautical monitoring of the frequency. RCCs are responsible for a geographic area, known as a "search-and-rescue region of responsibility" (SRR). SRRs are designated by the International Maritime Organization and the International Civil Aviation Organization . RCCs are operated unilaterally by personnel of a single military service (e.g. an air force, or a navy) or a single civilian service (e.g.

2538-539: Was designed for satellite detection and location. Since the inception of Cospas-Sarsat in 1982, distress radio beacons have assisted in the rescue of over 50,000 people in more than 7,000 distress situations. In 2010 alone, the system provided information used to rescue 2,388 persons in 641 distress situations. The several types of emergency locator beacons are distinguished by the environment for which they were designed to be used: Distress alerts transmitted from ELTs, EPIRBs, SSAS, and PLBs are received and processed by

2592-414: Was known that she had had a few groundings prior to the accident – experts investigated by the MAIB said that this was not uncommon for ships participating in races. The connection between hull, matrix and keel had been repaired several times already. Even experts are not normally capable of telling how such a repair would be properly done and how to tell that it was acceptably fixed. The recommendation from

2646-414: Was made possible by Doppler processing. Local-user terminals (LUTs) detecting nongeostationary satellites interpret the Doppler frequency shift heard by LEOSAR and MEOSAR satellites as they pass over a beacon transmitting at a fixed frequency. The interpretation determines both bearing and range. The range and bearing are measured from the rate of change of the heard frequency, which varies both according to

2700-494: Was missing, but the rudder was still in place. Due to bad weather conditions, the wreck could not be investigated further. Only about one week later could a ship of the United States Navy send a diver to the still-floating wreck. This confirmed the life raft was still secured to its storage location; the crew had not had the time to bring it out. Consequently, the search was terminated, because any hope of finding

2754-427: Was not much wind, but it was constantly increasing after May 10. On May 16, the wind blew with Force 7 and a considerable sea had built up. The skipper reported to shore that the ship was taking on significant amounts of water for no apparent reason. A later phone call was incomprehensible, such that the director called MRCC Falmouth for help. A search-and-rescue operation was started. RCC Boston , responsible for

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2808-404: Was supposed to return to Southampton , England afterwards, to be available as charter yacht the following season. She left Antigua on May, 4 with a crew of four men on board. The voyage was expected to take about 30 days. During the voyage, the skipper exchanged emails with the director of Stormforce over satellite phone , especially about route suggestions and weather reports. Initially, there

2862-404: Was the 121.5 MHz ELT, which was designed as an automatic locator beacon for crashed military aircraft. These beacons were first used in the 1950s by the U.S. military, and were mandated for use on many types of commercial and general-aviation aircraft beginning in the early 1970s. The frequency and signal format used by the ELT beacons was not designed for satellite detection, which resulted in

2916-401: Was used to locate the beacon(s). Multiple beacons were separated when a computer program analysed the signals with a fast Fourier transform . Also, two satellite passes per beacon were used. This eliminated false alarms by using two measurements to verify the beacon's location from two different bearings. This prevented false alarms from VHF channels that affected a single satellite. Regrettably,

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