title: Bangui

text: Under pressure from a donor group called GIBAFOR (France, USA, Japan, Germany, EU, World Bank and the UN) Kolingba made moves to restore a degree of democracy in the country in 1991 with a multiparty government. Elections were held in 1993 and 1994. The first round was sabotaged by the government when it was clear they would lose. Under continued donor pressure elections were held again in 1994 as before with help from the UN electoral Assistance Unit. During these elections, Ange-Félix Patassé was elected to the post of president. Since he was from northern CAR, the southern group of Kolingba started a rebellion during 1996.


title: Bangui

text: In May 1996, about 200 soldiers of the Central African Republic mutinied in Bangui, demanding salary increases and the abdication of Ange-Félix Patassé. In the aftermath, the renegades plundered and killed more than 50 people. Following this, the French troops stationed in the country suppressed the rebellion and restored the dictatorial power. After being elected, President Patassé announced a national unity government in early 1997. The Patassé government, the opposition parties, and religious groups signed the Bangui Agreements in January 1997 which were a series of measures designed to reconcile competing political factions, reform and strengthen the economy. The same year, the rebel troops refused a military base in Bangui and in June a new revolt broke out.


title: Bangui

text: In view of frequent political unrest the city was named in 1996 as one of the most dangerous cities in the world. On 25 October 2002, several towns in the country and later Bangui itself were attacked by the forces of General François Bozizé, backed with international support. Bozizé refused to accept an arrest warrant and "defected with about a hundred troops, engaged in street battles in the northern neighborhoods of Bangui (traditionally supporting Patassé)" and went north. Bozizé went into exile in Chad but his troops returned to Bangui and fighting continued. Peace-keeping forces were ineffective, leaving Patassé isolated, and with support from Chad, Bozizé's troops were successful in removing Patassé's government. Patassé, who was returning from Niger after attending a conference, was not permitted to land in Bangui and he took asylum in Togo, and Bozizé seized power and suspended the constitution. An all-party National Transitional Government was set up which functioned as an interim legislative body. However, the "climate of distrust continued".


title: Bangui

text: In late 2012, the Séléka coalition rebelled against his autocratic rule and entered the city. After capturing Bria, Sibut, and other important towns, they were on the verge of capturing Damara, the last strategic town before Bangui. France and the US refused to support the president and neighbouring countries reinforced the Central African Multinational Force (Fomac).


title: Bangui

text: In January 2013, the rebels terminated their operations, hoping for a negotiated settlement. Following a ceasefire and a power-sharing agreement, Séléka and Bozizé agreed to honour the rebel's demands for the release of rebel prisoners and the expulsion of foreign troops from the country. The agreement allowed Bozizé to complete his term in office and to include members of Séléka in a new government. It was also agreed that fresh elections would be held in 2016. The agreement was not honoured and the rebels captured Bangui on 23 March 2013, forcing Bozizé to flee the capital.


title: Bangui

text: As of early January 2014, "around 500,000 have fled their homes" in Bangui, "almost half the city's population."


title: Bangui

text: Bangui, close to the country's southern border, lies on the northern banks of the Ubangi River just below a series of rapids that limit major commercial shipping upriver. The only major city located on the river, it covers an area of . The navigable Ubangi River, with the backdrop of lush green hills, turns sharply south below Bangui and connects to the Congo River just south of the equator near Brazzaville as its chief northern tributary. The Ubangi river marks the border between the Central African Republic and the Democratic Republic of the Congo. The Congolese town of Zongo is situated across the river from Bangui. The river flows to the east of downtown Bangui. During the rainy season the discharge in the river is three times higher than during the rest of the year. The city was also known as "La Coquette" (the beautiful city) in the 1970s.


title: Bangui

text: Close to the river, the city centre features a large arch dedicated to Bokassa as well as the presidential palace and the central market. Lying further north, the heart of the residential area has the largest market and most of the nightlife. Many of those in the suburbs live in houses known as Kodros, built of mud bricks with a thatched roof.


title: Bangui

text: The Bangui Magnetic Anomaly, one of the earth's largest crustal anomalies and the largest in Africa, has its centre in Bangui." It takes the form of a huge ellipse of x , with its central point at 6 degrees north and 18 degrees east. It consists of three parts or segments, which comprise the northern, the southern and the central anomalies. The magnetic equator passes through the feature's centre. Although it is well documented, the feature's origins are not fully understood.


title: Bangui

text: The Central African Republic is situated just north of the Equator with daily temperatures normally reaching at least 30 degrees Celsius. Bangui, close to the Equator in the south of the country, is slightly hotter and wetter than the northern regions. It has a tropical savanna climate (Köppen: Aw) with dry winters. While the warm season is from 23 January to 18 March, the cold season lasts from 20 June to 27 August, when rainfall is frequently accompanied by thunderstorms. The city is bordered by thick tropical rainforests along the river banks. Several of its neighbourhoods are in low-lying areas prone to recurrent flooding. Severe rains in June and July 2009 left 11,000 people homeless.


title: Bangui

text: After the Central African Republic attained independence in 1960, developmental activities began, and the urbanization of Bangui ensued. This is evidenced by the population growth from 279,800 in 1975 to 427,435 in 1988 to 524,000 by 1994, and to 652,000 in 2001. Apart from the ethnic people of the country, the city is also home for a minority group of Greek, Portuguese and Yemeni traders, and also has a small community of French people. The Bangui resident community includes diamond traders from western Africa and Chad, traders from many African countries, and refugees from the Democratic Republic of the Congo and Nigeria.


title: Bangui

text: The official languages of the country are French and Sango; the latter (originally a language from the Ubangi River region) is spoken by 90% of the population. Some of the other languages spoken are Baya (Gbaya), Banda, Ngbaka, Sara, Mbum, Kare, and Mandjia. Sango was simplified by Christian missionaries and is widely used to this day.


title: Bangui

text: Bangui serves as an administrative, trade, and commercial centre. During the Second World War the country became wealthier as exports of rubber, cotton, coffee, uranium and diamonds increased. After the war, the employment of local people in mainstream administration led to the development of the country's infrastructure, which increased trade while slowing the national movement for independence.


title: Bangui

text: During David Dacko's presidency from 1960 to 1966, there was a significant increase in the production of diamonds. This occurred when the monopoly of the French concessionary companies was ended with a law allowing local citizens to dig for diamonds. After Dacko set up a diamond cutting factory at Bangui, diamonds became the country's leading export. But by the end of his five-year tenure, rampant corruption and financial indiscipline had resulted in workers being left unpaid and civil unrest ensued. Bokassa then seized power in a military coup in 1966.


title: Bangui

text: Concurrently, Bangui also became the key centre for social and cultural activity in the region, when new institutions were established in the city. However, political turmoil in the country, rampant corruption, and the dictatorial rule of President Bokassa centred in the city, brought in economic recession in the 1970s exacerbated by a fall in international prices for its major exports. This caused impoverishment of the people and severe conflict, further compounded by refugees migrating from troubled neighbouring countries.


title: Bangui

text: Bangui received its first bank in 1946 when a branch of the Bank of West Africa was established there. Arab sellers dominated the city, and it was historically an important centre for ivory trading. Bangui manufactures include textiles, food products, beer, shoes, and soap. The main exports are cotton, rubber, timber, coffee, and sisal. Because of the ongoing strife, unemployment hovered near 23% in the city . Ngaragba Central Prison, the national prison for men, is located in Bangui. , it had 476 inmates; prison conditions are reported to be poor.


title: Bangui

text: The old town of Bangui has retained its colonial town planning with wide boulevards leading towards central market square. Attractions in Bangui include Boganda Museum, Bangui Zoo, and the Presidential Palace, formerly the Bokassa Palace. Notre-Dame Cathedral is the seat of the Roman Catholic Archdiocese of Bangui. Boganda Museum ("Musée de Boganda") has displays of traditional musical instruments, weapons, rural architectural features, ancient hunting tools, pottery, and also many religious antiques. It has a collection of bark cloth, the material used to cover Bokassa's bed.


title: Bangui

text: There are several hotels up to international standards. The Ledger Plaza Bangui on the outskirts claims to be a five-star hotel, and has an outdoor swimming pool and tennis court. The National Hotel was established in 1970 with 30 rooms. Also of note are the Golf Palace Hotel, the Hotel du Centre with 72 rooms, JM Residence, the Oubangui Hotel, established in 1985, and Hotel Somba with 23 rooms.


title: Bangui

text: Polygamy is an accepted practice among men. When someone dies in Bangui, a representative from his or her village always attends the funeral. "This person is charged with indicating to the deceased the way back home so that the deceased may avenge himself and herself and demonstrate the power of the family". The representative who attends the funeral also carries a little dust from the grave to the village, and gives it to the village's holy medicine man so that he can ascertain the reasons for his death.


title: Bangui

text: Most of the holidays in Bangui are festivals related to the Christian and Muslim faiths and are the same as those observed in other parts of the world. National holidays include independence day and the birthdays of Boganda and several other national heroes.


title: Bangui

text: The cuisine of CAR is referred to as Centrafrican and the staple diet in Bangui includes cassava, rice, squash, pumpkins and plantains served with a sauce and grilled meat. Okra or "gombo" is a popular vegetable. Peanuts and peanut butter are widely used. Game is popular, as are the fish-based dishes "maboké" and "soussou". Manioc flour is used for preparing fufu.


title: Bangui

text: There are three types of restaurants in Bangui. Some focus on foreign cuisine, such as 'Relais des Chasses,' 'La Tentation' and 'L'Escale,' which are oriented towards French food, and 'Ali Baba' and 'Beyrouth,' which serve Lebanese food. There are a large number of African restaurants, such as the "Madame M'boka," a favorite of the locals. A number of bars and street food stalls complement Bangui's culinary scene. Alcoholic beverages served are locally brewed beer, palm wine and banana wine. Non-alcoholic beverages that are drunk include ginger beer.


title: Bangui

text: Bangui's artisans' market has traditional wares representing the art products from different regions of the country. Handicrafts include woven mats and baskets, wooden utensils of simple design, carved stools, pottery, musical instruments, tanned skins, and wood products. The balafon, similar to a xylophone, is made out of the horns of animals. Innovative designs include butterfly wings stuck with gum on paper, and ebony and hardwood carvings of wood from the tropical region. Artwork also covers carved animals and human figures. The crafts center in Bangui provides training to about 100 students in artistic crafting in leather, ivory and ebony wares.


title: Bangui

text: Bangui has a rich music tradition and showcases the country's music. Its musicians also perform in many countries abroad. The Bangui band groups were influenced by Zokela in the 1980s. The innovative music is based on dance bands who have adopted the Congolese music with electronic support. The music is rhythmic and blends with the Congolese rumba (soukous), which was influenced by son cubano, cha-cha-cha, and merengue. Popular Central African music groups or dance bands who perform in the city are Musiki, Zokela, Makembe, Cool Stars, Cannon Stars, and Super Stars. Bokassa, during his tenure as president, established a music recording studio in Bangui and employed musicians to sing his praise with songs extolling his qualities as an emperor and to develop his cult image among his people.


title: Bangui

text: The most popular sport is basketball. Bangui hosted the FIBA Africa Championship 1974, where the Central African Republic's national basketball team won one of its two continental titles.


title: Bangui

text: Football (soccer) is also popular. Both men and women from Bangui and throughout the country have participated in the Olympic Games since 1968 as well as in many international events. The locals also organize boat races with hundreds of participants on the Ubangi River, which is a significant attraction.


title: Bangui

text: The French system of education is the norm and French is the language of teaching, although the Sango language is promoted in schools. A substantial percentage of the population is literate. Schooling is compulsory for children ages 6 to 14.


title: Bangui

text: Bangui is home to the University of Bangui, founded in 1969 by President Jean-Bédel Bokassa who named it after himself; it started functioning in 1970. A public institution, the university provides non-agricultural education in the Central African Republic. Since 1981, the University Library has been in a separate building that houses its science, literature, and law collections. The medical school of the university has its own library.


title: Bangui

text: The other educational institutions are the National School of Arts and the Central School of Agriculture, in addition to many religious and technical schools.


title: Bangui

text: A school in the eastern part of the city, Lycée Charles de Gaulle, was established by the French and is named after President of France Charles de Gaulle. Several notable Africans, including writers such as Calixthe Beyala, have studied in the city. Beyala studied at the Lycée des Rapides.


title: Bangui

text: Among the places of worship, they are predominantly Christian churches and temples: Roman Catholic Archdiocese of Bangui (Catholic Church), Evangelical Lutheran Church of the Central African Republic (Lutheran World Federation), Evangelical Baptist Church of the Central African Republic (Baptist World Alliance). There are also Muslim mosques.


title: Bangui

text: Bangui is the transport hub of the Central African Republic. As of 1999, eight roads connected the city to other main towns in the country, Cameroon, Chad and South Sudan; of these, only the toll roads are paved. During the rainy season from March to November, some roads are impassable. The road network in the city emanates from the Palace de la Republique.


title: Bangui

text: River ferries sail from the river port at Bangui to Brazzaville and Zongo. The river can be navigated most of the year between Bangui and Brazzaville. From Brazzaville, goods are transported by rail to Pointe-Noire, Congo's Atlantic port. The river port handles the overwhelming majority of the country's international trade and has a cargo handling capacity of 350,000 tons; it has length of wharfs and of warehousing space.


title: Bangui

text: The first airstrip in Bangui was built between 1920 and 1925. Bangui M'Poko International Airport is located on of deforested land off the Avenue of Martyrs to the north of the old town, between the Koudoukou Avenue and the University of Bangui.


title: Bangui

text: A general hospital is located in the eastern side of the city. Modern health care facilities exist only in Bangui but are poor, providing only minimal care. Wealthier citizens make use of private clinics. The risk of catching HIV in the city is reportedly high, and many truck drivers stopping in the city for sexual services pose a major risk of spreading the disease to other parts of the country. The risk of catching malaria in Bangui and pygmy camps is also much higher than in the rest of the country.


title: Bangui

text: A conference of public health officials including representatives of the Centers for Disease Control and the World Health Organization was held in Bangui in October 1985. The conference evolved a diagnostic definition of AIDS which came to be known as the Bangui definition for AIDS. The conference defined symptoms of AIDS in Africa as "prolonged fever for a month or more, weight loss of over 10% and prolonged diarrhea". The Bangui definition proved problematic as immune suppression can also be caused by malnutrition.


title: Bangui

text: Several periodicals and three daily newspapers are published in Bangui: "E le Songo", the country's first newspaper, began publication in 1982. The other main newspapers are "Le Novateur", "Le Citoyen" and "L’Echo de Centrafrique". Most of the country's institutions have offices in Bangui, including French ones such as Électricité de France (EDF).


title: Bangui

text: Radio stations operating in Bangui include "Radio Centrafrique", Radio Nehemie, Radio Notre-Dame, Radio Voix de la paix, Radio Ndeke Luka, RFI, Radio Voik de la grace, Radio Linga FM, Africa no.1, and Tropic FM. BBC World Service is the only English broadcasting station that is heard in the city on 90.2 FM, as all other local channels broadcast in either French and/or Sango. For reliable news, the channel of UN run Radio Ndeke Luka is on 100.8 FM.


title: Camp Speicher massacre

text: The Camp Speicher massacre occurred on 12 June 2014, when the Islamic State killed between 1,095 to 1,700 Iraqi cadets in an attack on Camp Speicher in Tikrit, Iraq. At the time of the massacre, there were between 5,000 and 100,000 unarmed cadets in the camp, and ISIL fighters selected the Shias and non-Muslims for execution. It is the second deadliest act of terrorism in history, only surpassed by the September 11 attacks.


title: Camp Speicher massacre

text: Several survivors later testified that their senior officers in the camp had forced them to leave the camp. Hassan Khalil, one survivor, who managed to escape by pretending to be dead under another corpse and fleeing at night, said: "Our chief officers are the reason behind the killings. They forced us to leave Speicher. They assured us there was a safe passage, that it was guarded by the tribes, and told us not to wear uniforms." "They sold us to ISIS" he added. The Iraqi government and national television denied that story. They said the cadets forced their way out of the camps after the military had already dispatched special forces to the dangerous camps' area to secure them, and that they'd been warned against leaving.


title: Camp Speicher massacre

text: 400 cadets ordered to leave Camp Speicher before the attack were arrested by government forces and are missing.


title: Camp Speicher massacre

text: Peter Bouckaert, the emergencies director for Human Rights Watch (HRW), stated: "The photos and satellite images from Tikrit provide strong evidence of a horrible war crime that needs further investigation. [ISIS] and other abusive forces should know that the eyes of Iraqis and the world are watching".


title: Camp Speicher massacre

text: The photos show masked ISIL fighters tying up the cadets and loading them up on trucks, with other photographs showing ISIL fighters killing dozens of the cadets with assault rifles while they are lying down. ISIL propaganda videos show them shooting at hundreds of men lined up in mass graves in the desert. Some cadets faked their death, covering themselves with blood and escaping at night. Survivor Ali Hussein Kadhim told his story to "The New York Times" following his escape from the massacre.


title: Camp Speicher massacre

text: ISIL released footage of the massacre as part of their propaganda video "Upon the Prophetic Methodology". The cadets are seen being crammed into trucks, some of them wearing civilian clothes to hide their military uniforms. Most of them are lying on the ground, with their jeans stripped to reveal camouflage uniforms underneath. Some of the prisoners were forced to defame Iraq's prime minister, Nouri al-Maliki, while others were forced to shout "long live the Islamic State". Some of them were beaten to death with a rifle. The killing methods varied, from shooting the cadets one by one to shooting them while lying down many times to ensure death. Some cadets were shot and dumped into the Tigris river.


title: Camp Speicher massacre

text: The Iraqi government said that 57 members of the Arab Socialist Ba'ath Party had taken part in the massacre. Although pictures showed that every armed man was from ISIS, the government stated "Without any doubts and suspicion, all of these criminals are from the banned Ba'ath Party." The Minister of Defense, Sa'dun al-Dulaimi, stated that the massacre was not sectarian in nature. Although the spokesman of the Iraqi Armed Forces, Qasim Atta, stated that there were almost 11,000 cadets and soldiers missing from Camp Speicher; he also stated that thousands were executed in or near the presidential palaces, the al-Bu Agail region, and the Badoush prison by sectarian violence.


title: Camp Speicher massacre

text: On 2 September, more than 100 members of the families of the killed and missing cadets and soldiers broke into the Iraqi Parliament and hit three of the security guards. After a day, a session started in the parliament with the attendance of representatives of the families and Sa'dun al-Dulaimi, along with other military officials to discuss the massacre.


title: Camp Speicher massacre

text: On 16 September, the Kurdish Asayish arrested four people suspected to be involved in the massacre in southern Kirkuk. An unnamed security source stated, "The operation was executed by relying on intelligence information to arrest them."


title: Camp Speicher massacre

text: On 18 September, the Iraqi Human Rights ministry stated that as of 17 September, the total number of missing soldiers and cadets was 1,095, denying the most popular figure of 1,700 soldiers having been killed. The ministry added, "The ministry relied in its statistics on spreading forms on the families of the missing people in Baghdad and the other governorate within its quest to document the crimes and violations that the terrorist group of the Islamic State is committing towards our people." The Iraqi government ordered them to pay 10 million Iraqi dinar (equivalent to US$8,600) to the families of the missing cadets.


title: Camp Speicher massacre

text: Following the Iraqi forces' victory over ISIL in Tikrit in early April 2015, mass graves containing some of the murdered cadets were located and the decomposed corpses began to be exhumed. Two of the alleged perpetrators of the massacre were arrested in Forssa, Finland, in December 2015. The suspects were identified from ISIL propaganda videos in which the executions of 11 men took place. Police did not disclose whether the men had made applications for asylum in Finland. On 13 December 2016, the 24-year-old twins were charged with murder and committing a war crime for allegedly killing unarmed cadets, as well as "aggravated assault with terrorist aims". They were acquitted by the Pirkanmaa District Court in May 2017. After the prosecution appealed the ruling they were again acquitted by the Turku Court of Appeal in February 2020 due to lack of evidence for the involvement of the brothers in the massacre.


title: Camp Speicher massacre

text: In August 2016, 36 men were executed by hanging for their part in the massacre. On 6 September 2016, three mass graves were found by the Kata’ib al-Imam Ali brigade containing the remains of over 30 people killed in the massacre. In August 2017, 27 people were sentenced to death for their involvement in the massacre, and another 25 men were released due to lack of evidence.


title: Extraordinary rendition

text: Extraordinary rendition is a euphemism for state-sponsored forcible abduction in another jurisdiction and transfer to a third state. The phrase usually refers to a United States-led program used during the War on Terror, which had the purpose of circumventing the source country's laws on interrogation, detention, extradition and/or torture. Extraordinary rendition is a type of extraterritorial abduction, but not all extraterritorial abductions include transfer to a third country.


title: Extraordinary rendition

text: The administration of President George W. Bush abducted hundreds of "illegal combatants" for U.S. detention, and transported detainees to U.S.-controlled sites as part of an extensive interrogation program that included torture. Extraordinary rendition continued under the Obama administration, with targets being interrogated and subsequently taken to the U.S. for trial. A 2018 report by the Intelligence and Security Committee of Parliament found the United Kingdom, specifically MI5 and MI6, to be complicit in many of the renditions carried out by the U.S., by helping to fund them, by supplying intelligence, and by knowingly allowing the abductions to happen.


title: Extraordinary rendition

text: In July 2014, the European Court of Human Rights condemned the government of Poland for participating in CIA extraordinary rendition, ordering Poland to pay restitution to men who had been abducted, taken to a CIA black site in Poland, and tortured.


title: Extraordinary rendition

text: By 2004, critics alleged that torture was used against subjects with the knowledge or acquiescence of the United States, where the transfer of a person for the purpose of torture is unlawful. In addition, some former detainees, such as the Australian citizen Mamdouh Habib, claimed to have been transferred to other countries for interrogation under torture. In December 2005, then Secretary of State Condoleezza Rice insisted:


title: Extraordinary rendition

text: The United States has not transported anyone, and will not transport anyone, to a country when we believe he will be tortured. Where appropriate, the United States seeks assurances that transferred persons will not be tortured.


title: Extraordinary rendition

text: Between 2001 and 2005, CIA officers captured an estimated one hundred fifty people and transported them around the world.


title: Extraordinary rendition

text: Under the Bush administration, rendered persons were reported to have undergone torture by receiving countries. Journalists, civil and constitutional rights groups, and former detainees have alleged that this occurred with the knowledge or cooperation of the administrations of the United States and the United Kingdom.


title: Extraordinary rendition

text: Such revelations prompted several official investigations into alleged secret detentions and unlawful interstate transfers involving Council of Europe members. A June 2006 report estimated that one hundred people had been kidnapped by the CIA on European Union soil with the cooperation of Council of Europe members and rendered to other countries, often after having transited through secret detention centers ("black sites"), some located in Europe. According to the separate European Parliament report of February 2007, the CIA has conducted 1,245 flights, many of them to destinations where suspects could face torture, in violation of Article 3 of the United Nations Convention Against Torture. A large majority of the European Union Parliament endorsed the report's conclusion that many member states tolerated illegal actions by the CIA, criticizing several European governments and intelligence agencies for their unwillingness to cooperate with the investigation.


title: Extraordinary rendition

text: Within days of his 2009 inauguration, Barack Obama signed an executive order opposing rendition torture and established a task force to provide recommendations about processes to prevent rendition torture. His administration distanced itself from some of the harshest counterterrorism techniques but permitted the practice of rendition to continue, restricting transport of suspects to countries with jurisdiction over them for the purpose of prosecution after diplomatic assurances "that they [would] not be treated inhumanely" had been received.


title: Extraordinary rendition

text: Rendition, in law, is a transfer of persons from one jurisdiction to another, and the act of handing over, both after legal proceedings and according to law. "Extraordinary rendition," however, is a rendition that is extralegal, i.e. outside the law (see: kidnapping). Rendition refers to the transfer; the apprehension, detention, interrogation, and any other practices occurring before and after the movement and exchange of extrajudicial prisoners do not fall into the strict definition of "extraordinary rendition". In practice, the term is widely used to describe such practices, particularly the initial apprehension. This latter usage extends to the transfer of suspected terrorists by the US to countries known to torture prisoners or employ harsh interrogation techniques that may rise to the level of torture.


title: Extraordinary rendition

text: The Bush administration freely admitted to this practice; stating, among other provisions, that they have specifically asked that torture not be used. However, torture can still occur despite these provisions, and much documentation exists alleging that it has happened in many cases. In these instances, the initial captor allows the possibility of torture by releasing the prisoner into the custody of nations that practice torture.


title: Extraordinary rendition

text: The next distinction of degree is that of intent, where much of the search for evidence continues. It has been alleged that some of those detainees have been tortured with the knowledge, acquiescence, or even participation of US agencies. A transfer of anyone to anywhere for torture would be a violation of US law. New York attorney Marc D. Falkoff stated that such evidence, i.e. transfer for the purposes of torture, was an operational practice. In a court filing, Falkoff described a classified prisoner transfer memo from Guantanamo as noting that information could not be retrieved, as torture could not be used, and recommending that the prisoner be sent to a nation that practiced torture.


title: Extraordinary rendition

text: The American Civil Liberties Union alleges that extraordinary rendition was developed during the Clinton administration. CIA officials in the mid-1990s were trying to track down and dismantle militant Islamic organizations in the Middle East, particularly Al Qaeda.


title: Extraordinary rendition

text: Both the Reagan and Clinton cases involved apprehending known terrorists abroad, by covert means if necessary. The Bush administration expanded the policy after the 9/11 attacks.


title: Extraordinary rendition

text: In a "New Yorker" interview with CIA veteran Michael Scheuer, an author of the rendition program under the Clinton administration, writer Jane Mayer noted:


title: Extraordinary rendition

text: In 1995, American agents proposed the rendition program to Egypt, making clear that it had the resources to track, capture, and transport terrorist suspects globally — including access to a small fleet of aircraft. Egypt embraced the idea ... 'What was clever was that some of the senior people in Al Qaeda were Egyptian,' Scheuer said. 'It served American purposes to get these people arrested, and Egyptian purposes to get these people back, where they could be interrogated.' Technically, U.S. law requires the CIA to seek 'assurances' from foreign governments that rendered suspects won't be tortured. Scheuer told me that this was done, but he was 'not sure' if any documents confirming the arrangement were signed.


title: Extraordinary rendition

text: Scheuer testified in 2007 before Congress that no such assurances were received. He acknowledged that treatment of prisoners may not have been "up to U.S. standards":


title: Extraordinary rendition

text: This is a matter of no concern as the Rendition Program's goal was to protect America. The rendered fighters delivered to Middle Eastern governments are now either dead or in places from which they cannot harm America. Mission accomplished, as the saying goes.


title: Extraordinary rendition

text: Thereafter, with the approval of President Clinton and a presidential directive (PDD 39), the CIA elected to send suspects to Egypt, where they were turned over to the Egyptian Mukhabarat.


title: Extraordinary rendition

text: The CIA was granted permission to use rendition of indicted terrorists to American soil in a 1995 presidential directive signed by President Bill Clinton, following a procedure established by George H. W. Bush in January 1993.


title: Extraordinary rendition

text: The United States has since increasingly used rendition as a tool in the "war on terror", ignoring the normal extradition processes outlined in international law. Suspects taken into United States custody are delivered to third-party states, often without ever having been on United States soil, and without involving the rendering countries.


title: Extraordinary rendition

text: Critics have accused the CIA of employing rendition for the purpose of circumventing American laws mandating due process and prohibiting torture, labeling the practice "torture flights". Sociological comparisons have been drawn between extraordinary rendition and the death flights implemented, most notably, by Argentina during the 1960s and 1970s. Defenders of the practice argue that culturally informed and native-language interrogations are more successful in gaining information from suspects.


title: Extraordinary rendition

text: Hundreds of documents retrieved from Libyan foreign ministry offices in Tripoli following the 2011 Libyan civil war show that the CIA and MI6 rendered suspects to Libyan authorities knowing they would be tortured.


title: Extraordinary rendition

text: In a number of cases, such as those of Khalid El-Masri and Maher Arar, suspects caught up in the procedure suffered lengthy detentions, despite ultimately being found innocent. The CIA reportedly launched an investigation into such incidents of "erroneous rendition".


title: Extraordinary rendition

text: Following the 11 September 2001 attacks the United States, in particular the CIA, has been accused of rendering hundreds of people suspected by the government of being terrorists—or of aiding and abetting terrorist organizations—to third-party states such as Egypt, Jordan, Morocco, and Uzbekistan. Such "ghost detainees" are kept outside judicial oversight, often without ever entering US territory, and may or may not ultimately be transferred to the custody of the United States.


title: Extraordinary rendition

text: Members of the Rendition Group follow a simple but standard procedure: Dressed head to toe in black, including masks, they blindfold and cut the clothes off their new captives, then administer an enema and sleeping drugs. They outfit detainees in a diaper and jumpsuit for what can be a day-long trip. Their destinations: either a detention facility operated by cooperative countries in the Middle East and Central Asia, including Afghanistan, or one of the CIA's own covert prisons—referred to in classified documents as "black sites", which at various times have been operated in eight countries, including several in Eastern Europe.


title: Extraordinary rendition

text: Following mounting scrutiny in Europe, including investigations held by the Swiss senator Dick Marty who released a public report in June 2006, the US Senate, in December 2005, was about to approve a measure that would include amendments requiring the Director of National Intelligence to provide regular, detailed updates about secret detention facilities maintained by the United States overseas, and to account for the treatment and condition of each prisoner.


title: Extraordinary rendition

text: Media reports describe suspects as being arrested, blindfolded, shackled, and sedated, or otherwise kidnapped, and transported by private jet or other means to the destination country. The reports also say that the rendering countries have provided interrogators with lists of questions.


title: Extraordinary rendition

text: On 4 October 2001, a secret arrangement was made in Brussels by all members of NATO. Lord George Robertson, British defense secretary and later NATO's secretary-general, would later explain NATO members agreed to provide "blanket overflight clearances for the United States and other allies' aircraft for military flights related to operations against terrorism."


title: Extraordinary rendition

text: On 23 October 2006, the "New Yorker" reported that Jeppesen, a subsidiary of Boeing, handled the logistical planning for the CIA's extraordinary rendition flights. The allegation is based on information from an ex-employee who quoted Bob Overby, managing director of the company as saying "We do all of the extraordinary rendition flights—you know, the torture flights. Let's face it, some of these flights end up that way. It certainly pays well." The article went on to suggest that this may make Jeppesen a potential defendant in a lawsuit by Khaled El-Masri. Jeppesen was named as a defendant in a lawsuit filed by the ACLU on 30 May 2007, on behalf of several other individuals who were allegedly subject to extraordinary rendition.


title: Extraordinary rendition

text: The suit was dismissed on 8 September 2010 by a federal appeals court because "going forward would reveal state secrets".


title: Extraordinary rendition

text: In 2005, "The Washington Post" and Human Rights Watch (HRW) published revelations concerning CIA flights and "black sites", covert prisons operated by the CIA and whose existence is denied by the US government. The European Parliament published a report in February 2007 concerning the use of such secret detention centers and extraordinary rendition ("See below"). These detention centers violate the European Convention on Human Rights (ECHR) and the UN Convention Against Torture, treaties that all EU member states are bound to follow.


title: Extraordinary rendition

text: According to ABC News two such facilities, in countries mentioned by Human Rights Watch, have been closed following the publicity. CIA officers say the captives were relocated to the North African desert. All but one of these 11 high-value al Qaeda prisoners were subjected to torture by the CIA, sometimes referred to as "enhanced interrogation techniques" authorized for use by about 14 CIA officers.


title: Extraordinary rendition

text: In January 2005, Swiss senator Dick Marty, representative at the Council of Europe in charge of the European investigations, concluded that 100 people had been kidnapped by the CIA in Europe—thus qualifying as ghost detainees—and then rendered to a country where they may have been tortured. Marty qualified the sequestration of Hassan Mustafa Osama Nasr (aka "Abu Omar") in Milan in February 2003 as a "perfect example of extraordinary rendition." (See below: The European investigation and its June 2006 report)


title: Extraordinary rendition

text: "The Guardian" reported on 5 December 2005, that the British government is "guilty of breaking international law if it knowingly allowed secret CIA "rendition" flights of terror suspects to land at UK airports, according to a report by American legal scholars."


title: Extraordinary rendition

text: According to "Raw Story", the Polish site identified by reporter Larisa Alexandrovna and Polish intelligence officer David Dastych is Stare Kiejkuty. In response to these allegations, former Polish intelligence chief, Zbigniew Siemiatkowski, embarked on a media blitz and claimed that the allegations made by Alexandrovna and Dastych were "...part of the domestic political battle in the US over who is to succeed current Republican President George W Bush," according to the German news agency Deutsche Presse Agentur."


title: Extraordinary rendition

text: The United States has also been accused of operating "floating prisons" to house and transport those arrested in its "War on Terror", according to human rights lawyers. They have claimed that the US has tried to conceal the numbers and whereabouts of detainees. Although no credible information to support these assertions has ever come to light, the alleged justification for prison ships is primarily to remove the ability for jihadists to target a fixed location to facilitate the escape of high value targets, commanders, operations chiefs etc.


title: Extraordinary rendition

text: Khalid El-Masri (born 1963) is a German citizen who was mistakenly abducted by the Macedonian police, and handed over to the U.S. CIA. While in CIA custody, he was flown to Afghanistan, where he was allegedly held in a black site, interrogated, beaten, strip-searched, sodomized, and subjected to other inhuman and degrading treatment, which at times escalated to torture, though none of those claims can be verified. After El-Masri held hunger strikes, and was detained for four months in the "Salt Pit", the CIA finally admitted his arrest was a mistake and released him. He is believed to be among an estimated 3,000 detainees, including several key leaders of al Qaeda, whom the CIA captured from 2001 to 2005, in its campaign to dismantle terrorist networks.


title: Extraordinary rendition

text: In 2003, Hassan Mustafa Osama Nasr (aka "Abu Omar") was kidnapped by the CIA in Milan (Italy), and deported to Egypt. His case has been characterized by the Swiss senator Dick Marty as a "perfect example of extraordinary rendition". Abu Omar was kidnapped as he walked to his mosque in Milan for noon prayers. He was transported on a Learjet (using the call sign SPAR 92) to Ramstein, Germany. SPAR (Special Air Resources) is the call sign used by US senior military officers and civilian VIPs for airlift transport. A second plane took him to Cairo, where he was imprisoned and, he claims, tortured.


title: Extraordinary rendition

text: In 2005, the Italian judge Guido Salvini issued a warrant for the arrest of 13 persons said to be agents or operatives of the CIA in association with Nasr's kidnapping. In December 2005, an Italian court issued a European arrest warrant against 22 CIA agents suspected of this kidnapping (including Robert Seldon Lady, Eliana Castaldo, Lt. Col. Joseph L. Romano, III, etc.). The CIA has not commented on the case, while Berlusconi's government has denied any knowledge of a kidnapping plot. Just after the 2006 Italian general elections, Roberto Castelli (Lega Nord), outgoing Justice Minister, declared to Italian prosecutors that he had not passed the extradition request to the US.


title: Extraordinary rendition

text: In 2005, "The Washington Post" reported Italian court documents which showed that the CIA tried to mislead Italian anti-terrorism police who were looking for the cleric at the time. Robert S. Lady, the CIA's substation chief in Milan, has been implicated in the abduction. In a written opinion upholding the arrest warrant, judge Enrico Manzi wrote that the evidence taken from Lady's home "removes any doubt about his participation in the preparatory phase of the abduction." Lady, however, alleged that the evidence had been gathered illegally, and has denied involvement in the abduction. Photos of Robert (Bob) Lady and other defendants surfaced on the Web.


title: Extraordinary rendition

text: Marco Mancini, the SISMI director of anti-terrorism and counterespionage, and Gustavo Pignero, the department's director in 2003, have been arrested on charges of complicity in a kidnapping, with the aggravating circumstances of abuse of power. Italian judges have issued 26 EU arrest warrants for U.S. citizens in connection with this event. A judge also issued arrest warrants for four Americans, three CIA agents and an Air Force officer who commanded the security forces at Aviano Air Base at the time of the abduction.


title: Extraordinary rendition

text: In 2009, an Italian judge convicted 22 suspected or known CIA agents, a U.S. Air Force (USAF) colonel, and two Italian secret agents of the kidnapping. These were the first legal convictions in the world against people involved in the CIA's extraordinary renditions program.


title: Extraordinary rendition

text: A story in the "Los Angeles Times" in 2005 seems to corroborate the claims of "torture by proxy." It mentions the attorneys for Majid Mahmud Abdu Ahmad, a detainee held by the Pentagon at Guantanamo Bay, filed a petition to prevent his being transferred to foreign countries. According to the petition's description of a redacted classified Defense Department memo from 2004, its contents say "officials suggested sending Ahmad to an unspecified foreign country that employed torture in order to increase chances of extracting information from him."


title: Extraordinary rendition

text: Mr Falkoff, representing Ahmad, continued: "There is only one meaning that can be gleaned from this short passage," the petition says. "The government believes that Mr. Ahmad has information that it wants but that it cannot extract without torturing him." The petition goes on to say that because torture is not allowed at Guantanamo, "the recommendation is that Mr. Ahmad should be sent to another country where he can be interrogated under torture."


title: Extraordinary rendition

text: In a report, regarding the allegations of CIA flights, on 13 December 2005, the rapporteur and Chair of the Parliamentary Assembly of the Council of Europe's Committee on Legal Affairs and Human Rights, Swiss councillor Dick Marty, concluded: "The elements we have gathered so far tend to reinforce the credibility of the allegations concerning the transport and temporary detention of detainees—outside all judicial procedure—in European countries."


title: Extraordinary rendition

text: In a press conference in January 2006, he stated ""he was personally convinced the US had undertaken illegal activities in Europe in transporting and detaining prisoners.""


title: Extraordinary rendition

text: Muhammad Bashmila, a former secret prisoner, now free in Yemen, gave an interview to the BBC "Newsnight" programme, where he spoke of being transferred from Afghanistan to a detention center where it was cold, where the food appeared European and where evening prayers were held. Somewhere in Eastern Europe is suspected. This claim cannot be confirmed.


title: Extraordinary rendition

text: Maher Arar, a Syrian-born dual Syrian and Canadian citizen, was detained at Kennedy International Airport on 26 September 2002, by US Immigration and Naturalization Service officials. He was heading home to Canada after a family holiday in Tunisia. After almost two weeks, enduring hours of interrogation chained, he was sent, shackled and bound, in a private jet to Jordan and then Syria, instead of being deported to Canada. There, he was interrogated and tortured by Syrian intelligence. Maher Arar was eventually released a year later. He told the BBC that he was repeatedly tortured during 10 months' detention in Syria—often whipped on the palms of his hands with metal cables. Syrian intelligence officers forced him to sign a confession linking him to Al Qaeda.


title: Extraordinary rendition

text: He was finally released following intervention by the Canadian government. The Canadian government lodged an official complaint with the US government protesting Arar's deportation. On 18 September 2006, a Canadian public enquiry presented its findings, entirely clearing Arar of any terrorist activities. In 2004 Arar filed a lawsuit in a federal court in New York against senior U.S. officials, on charges that whoever sent him to Syria knew he would be tortured by intelligence agents. US Attorney General John Ashcroft, Homeland Security Secretary Tom Ridge and FBI Director Robert Mueller were all named in the lawsuit. In 2009, a U.S. federal appeals court ruled that U.S. law did not allow victims of extraordinary rendition to sue U.S. officials for torture suffered overseas.


title: Extraordinary rendition

text: In 2006, Arar received the Letelier-Moffitt Human Rights Award from the Institute for Policy Studies for his ordeal. In 2007, Maher Arar received a public apology from the U.S. House of Representatives. U.S. Representative Dana Rohrabacher, who apologized, stated that he would fight any efforts to end the practice.


title: Extraordinary rendition

text: In 2007, Arar was awarded $10.5 million in compensation from the Canadian government for pain and suffering in his ordeal and a formal apology from Prime Minister Stephen Harper.


title: Extraordinary rendition

text: "This is a non-exhaustive list of some alleged examples of extraordinary rendition. Most cannot be confirmed."


title: Extraordinary rendition

text: On 25 November 2005, the lead investigator for the Council of Europe, Swiss lawmaker Dick Marty announced that he had obtained latitude and longitude coordinates for suspected black sites, and he was planning to use satellite imagery over the last several years as part of his investigation. On 28 November 2005, EU Justice Commissioner Franco Frattini asserted that any EU country which had operated a secret prison would have its voting rights suspended. In a preliminary report, Dick Marty declared that it was "doubtful that European governments, or at least their intelligence services, were unaware" of the CIA kidnapping of a "hundred" persons on European territory and their subsequent rendition to countries where they may be tortured.


title: Extraordinary rendition

text: The report from the Committee on Legal Affairs and Human Rights of the Council of Europe directed by Dick Marty, and made public on 7 June 2006, was titled: "Alleged secret detentions and unlawful inter-state transfers involving Council of Europe member states."


title: Extraordinary rendition

text: Following the publication of this report, the Council of Europe published its draft Recommendation and Resolution document which


title: Extraordinary rendition

text: found grounds for concern with the conduct of both the US and member states of the EU and expresses concern for the disregard of international law and the Geneva Convention. Following a 23-point resolution the document makes five recommendations.


title: Extraordinary rendition

text: Several months before the publication of the Council of Europe report directed by Dick Marty, Gijs de Vries, the EU's antiterrorism coordinator, asserted in April 2006 that no evidence existed that extraordinary rendition had been taking place in Europe. It was also said that the European Union's probe, and a similar one by the continent's leading human rights group had not found any human rights violations nor other crimes that could be proven to the satisfaction of the courts. This denial from a member of the executive power of the EU institutions has been questioned by the European Parliament report, which was accepted by a vast majority of the Parliament in February 2007 ("See below:The European Parliament's 14 February 2007 report").


title: Extraordinary rendition

text: On the other hand, Dick Marty explained the difference of approach concerning terrorism between the EU and the US as following:


title: Extraordinary rendition

text: While the states of the Old World have dealt with these threats primarily by means of existing institutions and legal systems, the United States appears to have made a fundamentally different choice: considering that neither conventional judicial instruments nor those established under the framework of the laws of war could effectively counter the new forms of international terrorism, it decided to develop new legal concepts. This legal approach is utterly alien to the European tradition and sensibility, and is clearly contrary to the European Convention on Human Rights and the Universal Declaration of Human Rights.


title: Extraordinary rendition

text: However, despite Marty's claims, the European Parliament investigations uncovered cooperation between European secret services and governments and the extraordinary renditions programs, making such a clear-cut distinction over-simplistic ("see below"). Dick Marty himself has not accepted such a dualistic approach, as he showed that for the British government also, the phenomenon of Islamic terrorism was alleged to be so grave that the balance of liberties had to be reconsidered. Marty's report stated that:


title: Extraordinary rendition

text: The compilation of so-called "black lists" of individuals and companies suspected of maintaining connections with organisations considered terrorist and the application of the associated sanctions clearly breach every principle of the fundamental right to a fair trial: no specific charges, no right to be heard, no right of appeal, no established procedure for removing one's name from the list.


title: Extraordinary rendition

text: The Parliamentary Assembly of the Council of Europe (PACE) accused the United States of operating a "clandestine spiderweb of disappearances, secret detentions and unlawful inter-state transfers" and called for EU regulations governing foreign intelligence services operating in Europe, and demanded "human rights clauses" in military base agreements with the USA.


title: Extraordinary rendition

text: The European Parliament launched its own investigation into the reports. In April 2006, MEPs leading the investigations expressed concerns that the CIA had conducted more than 1,000 secret flights over European territory since 2001, some to transfer terror suspects to countries that used torture. Investigators said that the same US agents and planes were involved over and over again. The Parliament adopted a resolution in July 2006 endorsing the Council of Europe's conclusions, midway through its own investigation into the alleged program.


title: Extraordinary rendition

text: "In a resolution passed on 14 February 2007 MEPs approved by a large majority (382 voting in favour, 256 against and 74 abstaining) their committee's final report, which criticized the rendition program and concluded that many European countries tolerated illegal CIA activities including secret flights over their territories. The countries named were: Austria, Belgium, Cyprus, Denmark, Germany, Greece, Ireland, Italy, Poland, Portugal, Romania, Spain, Sweden and the United Kingdom. The report ...


title: Extraordinary rendition

text: According to the report, the CIA had operated 1,245 flights, many of them to destinations where suspects could face torture. The Parliament also called for the creation of an independent investigation commission and the closure of the Guantanamo camp. According to Italian Socialist Giovanni Fava, who drafted the document, there was a "strong possibility" that the intelligence obtained under the illegal extraordinary rendition program had been passed on to EU governments who were aware of how it was obtained. The report also uncovered the use of secret detention facilities used in Europe, including Romania and Poland. The report defines extraordinary renditions as instances where "an individual suspected of involvement in terrorism is illegally abducted, arrested and/or transferred into the custody of US officials and/or transported to another country for interrogation which, in the majority of cases involves incommunicado detention and torture".


title: Extraordinary rendition

text: Manfred Nowak, a special reporter on torture, has catalogued in a 15-page U.N. report presented to the 191-member General Assembly that the United States, the United Kingdom, Canada, France, Sweden and Kyrgyzstan are violating international human rights conventions by deporting terrorist suspects to countries such as Egypt, Syria, Algeria and Uzbekistan, where they may have been tortured.


title: Extraordinary rendition

text: "The United States is holding at least 26 persons as "ghost detainees" at undisclosed locations outside of the United States," Human Rights Watch said on 1 December 2005, as it released a list naming some of the detainees. The detainees are being held indefinitely and incommunicado, without legal rights or access to counsel.


title: Extraordinary rendition

text: The World Policy Council, headed by Ambassador Horace Dawson and Senator Edward Brooke, criticized the Bush Administration in the area of civil and human rights for its policy on extraordinary rendition. The Council concluded in its report that extraordinary rendition


title: Extraordinary rendition

text: The French district attorney of Bobigny opened up an instruction (an investigation) in order "to verify the presence in Le Bourget Airport, on 20 July 2005, of the plane numbered N50BH." This instruction was opened following a complaint deposed in December 2005 by the "Ligue des droits de l'homme" (LDH) NGO ("Human Rights League") and the "International Federation of Human Rights Leagues" (FIDH) NGO on charges of "arbitrary detention", "crime of torture" and "non-respect of the rights of war prisoners". It has as objective to determine if the plane was used to transport CIA prisoners to Guantanamo Bay detainment camp and if the French authorities had knowledge of this stop. However, the lawyer defending the LDH declared that he was surprised that the instruction was only opened on 20 January 2006, and that no verifications had been done before.


title: Extraordinary rendition

text: On 2 December 2005, conservative newspaper "Le Figaro" had revealed the existence of two CIA planes that had landed in France, suspected of transporting CIA prisoners. But the instruction concerned only N50BH, which was a Gulfstream III, which would have landed at Le Bourget on 20 July 2005, coming from Oslo, Norway. The other aircraft is suspected to have landed in Brest on 31 March 2002. It was investigated by the Canadian authorities, as it would have been flying from St. John's, Newfoundland and Labrador in Canada, via Keflavík in Iceland before going to Turkey.


title: Extraordinary rendition

text: Business daily "Handelsblatt" reported 24 November 2005, that the CIA used an American military base in Germany to transport terrorism suspects without informing the German government. The "Berliner Zeitung" reported the following day there was documentation of 85 takeoffs and landings by planes with a "high probability" of being operated by the CIA, at Ramstein, the Rhein-Main Air Base and others. The newspaper cited experts and "plane-spotters" who observed the planes as responsible for the tally.


title: Extraordinary rendition

text: In January 2007 the German government indicted 13 alleged CIA operatives for the abduction in Macedonia, transport to Afghanistan, and torture of Khaled el-Masri, a German citizen mistakenly believed to be a terrorist. Spanish authorities identified the suspected CIA abduction team from hotel records after a stopover by their Boeing 737 in Palma de Mallorca. Names of the alleged occupants of the rendition aircraft were James Fairing, Jason Franklin, Michael Grady, Lyle Edgard Lumsden III, Eric Fain, Bryam Charles, Kirk James Bird, Walter Richard Gressbore, Patricia Rilroy, Jane Payne, James O'Hale, John Decker, and Hector Lorenzo.


title: Extraordinary rendition

text: Many of these names proved to be aliases. Investigations by news organizations including the "Los Angeles Times", "The Nation", and "Der Spiegel" identified James Kovalesky (alias James Richard Fairing), Harry Kirk Elarbee (alias Kirk James Bird), and Eric Robert Hume (alias Eric Matthew Fain) as pilots working for Aero Contractors, a CIA flight contractor based in Smithfield, N.C. CBS News identified Lyle Edgard Lumsden III as a US Army captain who "retired in 1992 from active duty, having served as a physician's assistant" whose last known address was "the Washington DC area".


title: Extraordinary rendition

text: None of the names or aliases in this case match those of the 26 alleged CIA agents prosecuted by Italy (see Imam Rapito affair below). However, the "Los Angeles Times" reported one of the pilots may have been involved in both incidents. "The New York Times" reported that the 13 alleged CIA operatives were charged in indictments issued in Spain and in Munich, but because of "intense political pressure from Washington" Germany never requested their extradition. In Germany, unlike Italy, defendants cannot be tried "in absentia".


title: Extraordinary rendition

text: In the "Abu Omar case" in Italy, Hassan Mustafa Osama Nasr (aka Abu Omar), an Islamist cleric, was kidnapped in a joint CIA–SISMI operation in Milan on 17 February 2003, transferred to the Aviano Air Base, and then flown to Egypt, where he was held until 11 February 2007, when an Egyptian court ruled his imprisonment was "unfounded". He claims he was abused on the Aviano Base and endured prolonged torture in Egypt. Italian prosecutors investigated the abduction, and indicted 26 US citizens including the head of CIA in Italy, Jeffrey W. Castelli. SISMI chief General Nicolò Pollari and second-in-command Marco Mancini were forced to resign, and were also indicted. On 4 November 2009, after a trial "in absentia", an Italian judge found 23 Americans (names listed here) and the two Italians guilty. The sentences ranged from five to eight years for the Americans and three years each for the Italians. The judge acquitted three American diplomats, citing diplomatic immunity, along with five Italian secret service agents, including the former chief, citing state secrecy. In 2010 an Italian appellate court confirmed most of the verdicts and increased the sentences of the 23 Americans. Among those convicted was Stephen R. Kappes, later the number two man at the CIA, Robert Seldon Lady, formerly CIA station Chief in Milan, Col. Joseph L. Romano, a U S Air Force officer, and asserted CIA agent Sabrina De Sousa, who unsuccessfully sued the US State Department to grant her diplomatic immunity and shield her from arrest.


title: Extraordinary rendition

text: These were the first convictions anywhere in the world arising from the CIA's practice of abducting terror suspects and transferring them to third countries where torture occurred. The US had tried but failed to obstruct the prosecutions by Italy's independent judiciary. Following the convictions the US used threats and diplomatic pressure to stop the Italian executive branch from issuing arrest warrants and extradition requests for the Americans.


title: Extraordinary rendition

text: The Irish government has come under internal and external pressure to inspect airplanes at Shannon Airport to investigate whether or not they contain extraordinary rendition captives.


title: Extraordinary rendition

text: Police at Shannon Airport said that they had received political instruction not to approach, search or otherwise interfere with US aircraft suspected of being involved in extraordinary rendition flights. Irish Justice Minister Dermot Ahern sought permission from the US for random inspection of US flights, to provide political "cover" to him in case rendition flights were revealed to have used Shannon; he believed at least three flights had done so.


title: Extraordinary rendition

text: The European Parliament has censured Ireland for its role in facilitating extraordinary rendition and taking insufficient or no measures to uphold its obligations under the UN CAT.


title: Extraordinary rendition

text: In 2002, the Council of Europe's then-Commissioner for Human Rights Alvaro Gil-Robles witnessed "a smaller version of Guantanamo", he told France's "Le Monde" newspaper.


title: Extraordinary rendition

text: Gil-Robles told the daily that he had inspected the centre, located within the US military's Camp Bondsteel in Kosovo, in 2002, to investigate reports of extrajudicial arrests by NATO-led peacekeepers.


title: Extraordinary rendition

text: Portugal opened up an investigation concerning CIA flights in February 2007, on the basis of declarations by Socialist MEP Ana Gomes and by Rui Costa Pinto, journalist of "Visão" review. The Portuguese general prosecutor, Cândida Almeida, head of the Central Investigation and Penal Action Department (DCIAP), announced the opening of investigations on 5 February 2007. They were to be centered on the issue of "torture or inhuman and cruel treatment," and instigated by allegations of "illegal activities and serious human rights violations" made by MEP Ana Gomes to the attorney general, Pinto Monteiro, on 26 January 2007. In February 2008, the UK NGO Reprieve published a report based on flight logs obtained by Ana Gomes, confirming that over 728 prisoners were flown to Guantánamo through Portuguese airspace, and hence through Portuguese jurisdiction, in at least 28 flights.


title: Extraordinary rendition

text: One of the most critic voice against the scarce collaboration provided by the Portuguese government to the European Parliament Commission which investigated CIA flights, Ana Gomes declared that, although she had no doubt that permission of these illegal flights were frequent during Durão Barroso (2002–2004) and Santana Lopes (2004–2005)' governments, "during the [Socialist] government of José Sócrates [2005– ], 24 flights which passed through Portuguese territory" are registered. Active in the TDIP commission, Ana Gomes complained about the Portuguese state's reluctance to provide information, leading her to tensions with the Foreign minister, Luís Amado, member of the same party. Ana Gomes declared herself satisfied with the opening of the investigations, but underlined that she had always claimed that a parliamentary inquiry would be necessary.


title: Extraordinary rendition

text: On the other hand, journalist Rui Costa Pinto was heard by the DCIAP, as he had written an article, refused by "Visão", about flights passing by Lajes Field, a Portuguese airbase used by the US Air Forces, in the Azores.


title: Extraordinary rendition

text: Franco Frattini the European Union Justice Commissioner requested an explanation from the governments of Poland and Romania about the accusations made by Dick Marty. Doris Mircea (Romanian spokeswoman in Brussels) replied to this in November 2007 in a letter stating "no person was kept illegally as a prisoner within Romanian jails and no illegal transfer of detainees passed through Romanian territory" and that that was the official finding of a committee of inquiry set up by the government to investigate the accusations.


title: Extraordinary rendition

text: In November 2005, Spanish newspaper "El País" reported that CIA planes had landed in the Canary Islands and in Palma de Mallorca. Spanish magistrate Baltasar Garzón, notable for his earlier attempt to prosecute Chilean dictator Augusto Pinochet, opened up an investigation concerning these landings which, according to Madrid, were made without official knowledge, thus being a breach of national sovereignty. Diplomatic cables exposed in 2010 by WikiLeaks suggest that the United States government including the American ambassador, worked with parts of the Spanish government to subvert the Spanish judicial process to control and ultimately stymie and thwart the investigation.


title: Extraordinary rendition

text: Extraordinary rendition provoked a diplomatic crisis between the United States and Sweden in 2006 when Swedish authorities put a stop to CIA rendition flights. In December 2001 Swedish police detained Ahmed Agiza and Muhammad al-Zery, two Egyptians who had been seeking asylum in Sweden. The police took them to Bromma airport in Stockholm, and then stood aside as masked alleged CIA operatives cut their clothes from their bodies, inserted drugged suppositories in their anuses, and dressed them in diapers and overalls, handcuffed and chained them and put them on an executive jet with American registration N379P. They were flown to Egypt, where they were imprisoned, beaten, and tortured according to extensive investigate reports by Swedish programme "Kalla fakta". A Swedish Parliamentary investigator concluded that the degrading and inhuman treatment of the two prisoners violated Swedish law. In 2006 the United Nations found Sweden had violated an international torture ban in its complicity in the CIA's transfer of al-Zari to Egypt. Sweden imposed strict rules on rendition flights, but Swedish Military Intelligence posing as airport personnel who boarded one of two subsequent extraordinary rendition flights in 2006 during a stopover at Stockholm's Arlanda International Airport found the Swedish restrictions were being ignored. In 2008 the Swedish government awarded al-Zery $500,000 in damages for the abuse he received in Sweden and the subsequent torture in Egypt.


title: Extraordinary rendition

text: After claims by Liberty that British airports had been used by the "CIA for extraordinary rendition flights, the Association of Chief Police Officers launched an investigation in November 2005. The report was published in June 2007 and found no evidence to support the claim. This was on the same day the Council of Europe released its report with evidence that the UK had colluded in extraordinary rendition, thus directly contradicting ACPO's findings. Liberty has challenged the findings and has stated that its original claims were based on "credible evidence".


title: Extraordinary rendition

text: In July 2007, the British government's Intelligence and Security Committee released their Rendition report, detailing U.S. and U.K. activities and policies.


title: Extraordinary rendition

text: On 21 February 2008, British Foreign Secretary David Miliband admitted (despite previous government denials) that two U.S. extraordinary rendition flights had stopped on Diego Garcia in 2002, a U.K. territory. When questioned as to whether the government had deliberately misled the public over rendition, the Foreign Secretary apologised and stated that the government had simply "made a mistake". His statement also laid out the current UK Government view on Extraordinary rendition;


title: Extraordinary rendition

text: A judicial inquiry, chaired by Sir Peter Gibson was announced by the government in July 2010, but was never formally launched and was scrapped in January 2012. According to the government, this was due to ongoing criminal investigations. In April 2012 the CIA and FBI won a court ruling in the US, exempting them from releasing documentation requested by British members of parliament. It later emerged that relevant 2002 flight records from Diego Garcia had been destroyed by water damage.


title: Extraordinary rendition

text: An article published on 5 December 2005, "The Washington Post" reported that the CIA's Inspector General was investigating what it calls erroneous renditions. The term appears to refer to cases in which innocent people were subjected to extraordinary rendition.


title: Extraordinary rendition

text: Khalid El-Masri is the most well-known person who is believed to have been subjected to the process of "extraordinary rendition", as a result of mistaken identity. Laid Saidi, an Algerian detained and tortured along with El-Masri, was apprehended apparently because of a taped telephone conversation in which the word "tirat", meaning "tires" in Arabic, was mistaken for the word "tairat", meaning "airplanes".


title: Extraordinary rendition

text: The Post's anonymous sources say that the Inspector General is looking into a number of similar cases—possibly as many as thirty innocent men who were captured and transported through what has been called "erroneous renditions".


title: Extraordinary rendition

text: A 27 December 2005 story quotes anonymous CIA insiders claiming there have been 10 or fewer such erroneous renditions.


title: Extraordinary rendition

text: I am glad the CIA is investigating the cases that they are aware of, but by definition you are not going to be aware of all such cases, when you have a process designed to avoid judicial safeguards.


title: Extraordinary rendition

text: Two days after President Barack Obama was sworn into office, on 22 January 2009, he signed an executive order entitled "Ensuring Lawful Interrogations". Overall, the executive order calls for more oversight of interrogation by third parties, but does not end extraordinary rendition. The section of the Executive Order relating to extraordinary rendition provides as follows:


title: Extraordinary rendition

text: On 2 November 2009 the Second Circuit Court of Appeals ruled that victims of extraordinary rendition cannot sue Washington for torture suffered overseas, because Congress has not authorized such lawsuits, in ruling on Canadian citizen Maher Arar's case. On 15 September 2010 PolitiFact.com wrote about the Obama administration's record on renditions:


title: Extraordinary rendition

text: The administration has announced new procedural safeguards concerning individuals who are sent to foreign countries. President Obama also promised to shut down the CIA-run "black sites," and there seems to be anecdotal evidence that extreme renditions are not happening, at least not as much as they did during the Bush administration. Still, human rights groups say that these safeguards are inadequate and that the DOJ Task Force recommendations still allow the U.S. to send individuals to foreign countries.


title: Extraordinary rendition

text: According to a report by the Open Society Foundations, 54 countries participated at one point or another with the CIA's extraordinary rendition program:


title: Quizlet

text: Quizlet is a multi-national American company that provides tools for studying and learning. It was founded by Andrew Sutherland in October 2005 and released to the public in January 2007. Quizlet's primary products include digital flash cards, matching games, practice electronic assessments, and live quizzes. As of December 2021, Quizlet has over 500 million user-generated flashcard sets, and more than 60 million active users according to Quizlet's website; moreover, it says that 2 in 3 USA high school students use Quizlet.


title: Quizlet

text: Quizlet was founded in 2005 by Andrew Sutherland as a studying tool to aid in memorization for his French class, which he "aced". Quizlet's blog, written mostly by Andrew in the earlier days of the company, claimed it reached 50,000 registered users in 252 days online.


title: Quizlet

text: On April 15, 2008, Quizlet made its first national TV appearance when Sutherland was featured on the Mike and Juliet Show. In the following two years, Quizlet reached its 1,000,000th registered user.


title: Quizlet

text: Until 2011, Quizlet shared staff and financial resources with the Collectors Weekly website. In 2015, Quizlet announced raising $12 million from Union Square Ventures, Costanoa Venture Capital, Altos Ventures, and Owl Ventures to expand its digital study tools and grow internationally.


title: Quizlet

text: In 2011, Quizlet added the ability to listen to content using text-to-speech. In August 2012, it released an app for the iPhone and iPad and shortly afterward one for Android devices.


title: Quizlet

text: Quizlet launched a redesign in August 2016 and hired Matt Glotzbach as CEO a few months earlier in May. Also in 2016, Quizlet launched "Quizlet Live", a real-time online matching game where teams compete to answer all 12 questions correctly without an incorrect answer along the way.


title: Quizlet

text: Glotzbach announced in 2018 that Quizlet would be opening offices in Denver, Colorado in 2018, announcing "a big vision at Quizlet to provide the most intelligent study tools in the world, and our expansion into Denver, a city with incredible tech ingenuity, will help us more quickly build the next generation of learning tools used by students everywhere". As of 2019, Andrew Sutherland is no longer with Quizlet or its board.


title: Quizlet

text: During the COVID-19 pandemic, Glotzbach announced he was opening Quizlet's premium service, Quizlet Teacher, for free to all users who have an account registered as a teacher.


title: Quizlet

text: As of August 1, 2022, Learn and Test modes became part of Quizlet Plus, meaning they are no longer free.


title: Quizlet

text: As a memorization tool, Quizlet lets registered users create sets of terms and definitions customized for their own needs. These sets of terms can then be accessible to students by studying a variety of modes.


title: Quizlet

text: Students on Quizlet may upload information that can be used to cheat within the classroom. In a survey at a High School in Orlando, a student was quoted saying "If someone put $100 in front of you, would you take it?", referring to the ease with which students can use platforms like Quizlet to cheat on schoolwork.


title: Quizlet

text: As of September 2022, Quizlet's website has an "Honor Code" requiring all users of the website to not misuse the platform for academic cheating.


title: Quizlet

text: Quizlet's API is no longer available. It used to allow developers to use any of the study sets made within Quizlet in their own programs.


title: Royal Thai Army

text: The Royal Thai Army or RTA (; ) is the army of Thailand and the oldest and largest branch of the Royal Thai Armed Forces.


title: Royal Thai Army

text: The Royal Thai Army is responsible for protecting the kingdom's sovereignty. The army was formed in 1874, partly as a response to new security threats following the 1855 Bowring Treaty with Britain, which opened the country for international trade.


title: Royal Thai Army

text: In modern era, the army has a long history of coups d'état and coup attempts. Its leadership continues to see coup-making as one role of the army.


title: Royal Thai Army

text: On 22 May 2014 the army deposed the government, appointed military officers to the national assembly, and on 21 August 2014 they elected the army's Commander in Chief, General Prayut Chan-o-cha, as prime minister. The general retired October 2014 to concentrate on political reform which he said would take at least a year, following which he promised national elections would be held.


title: Royal Thai Army

text: The existence of an information warfare unit participating in a cyber campaign against government critics was leaked to the public in late February 2020.


title: Royal Thai Army

text: In 2020 Twitter shut down a network of accounts which were engaged in information warfare. According to Twitter “Our investigation uncovered a network of accounts partaking in information operations that we can reliably link to the Royal Thai Army (RTA).” The operation had targeted the political opposition within Thailand. The Thai Army denied that they had been involved in the disinformation operation.


title: Royal Thai Army

text: The number of army generals is unclear. One point of comparison: as of 1 November 2019, the US Army had 322 general officers for a force of 471,990 troops. Saiyud Kerdphol is Thailand's oldest general, a veteran of World War II and Korea who retired in 1983 as supreme commander. During his tenure, general officer numbers were based on the number of troops under their command. , only 150–200 four-star generals occupy command positions. Speaking on the topic of army manpower, Saiyud declared that, "Everybody being a general is unbelievable. Full generals don't have a seat to sit in or a job to do."


title: Royal Thai Army

text: The commanders-in-chief of the Royal Thai Army (ผู้บัญชาการทหารบกไทย) is considered the most powerful position in the Royal Thai Armed Forces. As of 1 October 2020, the commander is General Narongpan Jitkaewthae.


title: Royal Thai Army

text: The creation of the 15th Infantry Division was announced in January 2005. Defence Minister, General Samphan Boonyanan, was quoted as saying that the new unit, dubbed the "Development Division", would not be a combat unit for fighting Islamic militants, but rather its main mission would be to assist local citizens and develop the region. The military will not ignore its general function of providing safety for the citizens of the region, he added. He said that troops for the new division would undergo training to give them a good understanding of local residents, the vast majority of whom are ethnic Malay Muslims. The division is in fact a transformation of the Pranburi-based 16th Infantry Division. It will now be headquartered at Fort Ingkhayutthaborihan in Pattani, complete with its battalions and companies of military police and communications and aviation personnel, he said. It will also have three separate infantry battalions, one each in Pattani, Yala, and Narathiwat. Each battalion will include three companies of medical, engineering, and psychological warfare personnel, he said. The government will allocate a budget of more than 18 billion baht for the division over the next four years.


title: Royal Thai Army

text: The 15th Infantry Division is being established as a permanent force to handle security problems in the Deep South. The division is based in Pattani and is expected to have a combined force of around 10,000. The establishment of this new division, approved by the government in 2005, has yet to be completed. As of this writing, some 7,000 troops deployed in the Deep South are affiliated to this division." In 2012, two new combat formations had been approved by the thai government. The new 7th Infantry Division is based at Mae Rim, near Chiang Mai, and the new 3rd Cavalry Division is based at Khon Kaen.


title: Royal Thai Army

text: The Army Tactical Level Advanced Simulation (ATLAS) is an interactive, distributed, constructive simulation used to conduct military Command Post Exercises (CPX). ATLAS displays a continuous terrain model, incorporates HLA 1516, and displays 1:250,000 and 1:50,000 maps and satellite imagery. ATLAS was developed between 2002 and 2005 through co-operation with the Army Command and General Staff College (CGSC).


title: Royal Thai Army

text: Army Medical Department (AMED) () belongs to the service segment of the Royal Thai Army. It is in charge of medical affairs, and providing medical care, both in the field and on base, training personnel in research and agriculture and supervising the other medical divisions within the Royal Thai Army.


title: Royal Thai Army

text: AMED observed 111 years of service in January 2011, with 110 years of service having been honoured by issue of a series of commemorative stamps. AMED operates Phramongkutklao Hospital in Bangkok and Ananda Mahidol Hospital in Lopburi, along with smaller hospitals at each fort, as well as Phramongkutklao College of Medicine (PCM).


title: Royal Thai Army

text: Royal Thai Army Aviation Center (กองบินทหารบกไทย) belongs to the service segment of the Royal Thai Army Areas:


title: Royal Thai Army

text: The army is divided into districts, whereby the first digit of the district indicates the army (first, second, third or fourth) responsible for its supervision. The names of forts are from locations or influential figures in Thailand's history. These are as follows:


title: Royal Thai Army

text: The army owns more than 30 golf courses nationwide. The army also owns boxing stadium, 100 petrol stations, racecourses, hotels, retail and coffee shops, and radio and television airwaves (by one count, the armed forces have ownership in 537 radio and TV stations). In early 2020, the army entered an agreement with the Finance Ministry to turn over to the ministry the management of businesses unrelated to the army's mission. In a related move, army commander General Apirat Kongsompong decreed that retired generals must move out of army-owned housing to free space for serving officers. , about 100 retired generals and colonels inhabit army accommodations. Some ex-generals, like PM Prayut Chan-o-cha and deputy PM Prawit Wongsuwan were exempted immediately from eviction because of their "contribution to society". The Thai Defence Ministry position is that there is no law prohibiting retired officers from occupying military housing.


title: Royal Thai Army

text: In January 2021, the RTA signed a memorandum of understanding with the Electricity Generating Authority of Thailand (EGAT) to study the feasibility of constructing solar farms on 4.5 million rai of army land to generate 30,000 megawatts of electricity. Following up, on 22 February 2021 a meeting was called by the President of Royal Thai Army Radio and Television Channel 5 with energy firms interested in winning a piece of what is projected to be a 600 billion baht project. The Energy Ministry was not represented at the meeting. Critics have questioned why the army is involved in energy procurement, in contravention of existing regulations, and why Thailand needs more electricity when it already has 59% reserve capacity and more capacity under construction.


title: Power amplifier classes

text: In electronics, power amplifier classes are letter symbols applied to different power amplifier types. The class gives a broad indication of an amplifier's characteristics and performance. The classes are related to the time period that the active amplifier device is passing current, expressed as a fraction of the period of a signal waveform applied to the input. A class A amplifier is conducting through all the period of the signal; Class B only for one-half the input period, class C for much less than half the input period. A Class D amplifier operates its output device in a switching manner; the fraction of the time that the device is conducting is adjusted so a pulse-width modulation output is obtained from the stage.


title: Power amplifier classes

text: Additional letter classes are defined for special-purpose amplifiers, with additional active elements or particular power supply improvements; sometimes a new letter symbol is used by a manufacturer to promote its proprietary design.


title: Power amplifier classes

text: Power amplifier circuits (output stages) are classified as A, B, AB and C for linear designs—and class D and E for switching designs. The classes are based on the proportion of each input cycle (conduction angle) during which an amplifying device passes current. The image of the conduction angle derives from amplifying a sinusoidal signal. If the device is always on, the conducting angle is 360°. If it is on for only half of each cycle, the angle is 180°. The angle of flow is closely related to the amplifier power efficiency.


title: Power amplifier classes

text: In the illustrations below, a bipolar junction transistor is shown as the amplifying device. However, the same attributes are found with MOSFETs or vacuum tubes.


title: Power amplifier classes

text: In a class-A amplifier, 100% of the input signal is used (conduction angle Θ = 360°). The active element remains conducting all of the time.


title: Power amplifier classes

text: Amplifying devices operating in class A conduct over the entire range of the input cycle. A "class-A amplifier" is distinguished by the output stage devices being biased for class A operation. Subclass A2 is sometimes used to refer to vacuum-tube class-A stages that drive the grid slightly positive on signal peaks for slightly more power than normal class A (A1; where the grid is always negative). This, however, incurs higher signal distortion.


title: Power amplifier classes

text: Class-A power amplifier designs have largely been superseded by more efficient designs, though their simplicity makes them popular with some hobbyists. There is a market for expensive high fidelity class-A amps considered a "cult item" among audiophiles mainly for their absence of crossover distortion and reduced odd-harmonic and high-order harmonic distortion. Class A power amplifiers are also used in some "boutique" guitar amplifiers due to their unique tonal quality and for reproducing vintage tones.


title: Power amplifier classes

text: Some hobbyists who prefer class-A amplifiers also prefer the use of thermionic valve (tube) designs instead of transistors, for several reasons:


title: Power amplifier classes

text: Transistors are much less expensive than tubes so more elaborate designs that use more parts are still less expensive to manufacture than tube designs. A classic application for a pair of class-A devices is the long-tailed pair, which is exceptionally linear, and forms the basis of many more complex circuits, including many audio amplifiers and almost all op-amps.


title: Power amplifier classes

text: Class-A amplifiers may be used in output stages of op-amps (although the accuracy of the bias in low cost op-amps such as the "741" may result in class A or class AB or class B performance, varying from device to device or with temperature). They are sometimes used as medium-power, low-efficiency, and high-cost audio power amplifiers. The power consumption is unrelated to the output power. At idle (no input), the power consumption is essentially the same as at high output volume. The result is low efficiency and high heat dissipation.


title: Power amplifier classes

text: In a class-B amplifier, the active device conducts for 180 degrees of the cycle. This would cause intolerable distortion if there were only one device, so two devices are usually used, especially at audio frequencies. Each conducts for one half (180°) of the signal cycle, and the device currents are combined so that the load current is continuous.


title: Power amplifier classes

text: At radio frequency, if the coupling to the load is via a tuned circuit, a single device operating in class B can be used because the stored energy in the tuned circuit supplies the "missing" half of the waveform. Devices operating in Class B are used in linear amplifiers, so called because the radio frequency output power is proportional to the square of the input excitation voltage. This characteristic prevents distortion of amplitude-modulated or frequency-modulated signals passing through the amplifier. Such amplifiers have an efficiency around 60%.


title: Power amplifier classes

text: When Class-B amplifiers amplify the signal with two active devices, each operates over one half of the cycle. Efficiency is much improved over class-A amplifiers. Class-B amplifiers are also favoured in battery-operated devices, such as transistor radios. Class B has a maximum theoretical efficiency of π/4 (≈ 78.5%).


title: Power amplifier classes

text: A practical circuit using class-B elements is the push–pull stage, such as the very simplified complementary pair arrangement shown at right. Complementary devices are each used for amplifying the opposite halves of the input signal, which is then recombined at the output. This arrangement gives good efficiency, but usually suffers from the drawback that there is a small mismatch in the cross-over region at the "joins" between the two halves of the signal, as one output device has to take over supplying power exactly as the other finishes. This is called crossover distortion. An improvement is to bias the devices so they are not completely off when they are not in use. This approach is called "class AB" operation.


title: Power amplifier classes

text: In a class-AB amplifier, the conduction angle is intermediate between class A and B; each one of the two active elements conducts more than half of the time.


title: Power amplifier classes

text: Class AB is widely considered a good compromise for amplifiers, since much of the time the music signal is quiet enough that the signal stays in the "class-A" region, where it is amplified with good fidelity, and by definition if passing out of this region, is large enough that the distortion products typical of class B are relatively small. The crossover distortion can be reduced further by using negative feedback.


title: Power amplifier classes

text: In class-AB operation, each device operates the same way as in class B over half the waveform, but also conducts a small amount on the other half. As a result, the region where both devices simultaneously are nearly off (the "dead zone") is reduced. The result is that when the waveforms from the two devices are combined, the crossover is greatly minimised or eliminated altogether. The exact choice of quiescent current (the standing current through both devices when there is no signal) makes a large difference to the level of distortion (and to the risk of thermal runaway, which may damage the devices). Often, bias voltage applied to set this quiescent current must be adjusted with the temperature of the output transistors. (For example, in the circuit shown at right, the diodes would be mounted physically close to the output transistors, and specified to have a matched temperature coefficient.) Another approach (often used with thermally tracking bias voltages) is to include small value resistors in series with the emitters.


title: Power amplifier classes

text: Class AB sacrifices some efficiency over class B in favor of linearity, thus is less efficient (below 78.5% for full-amplitude sine waves in transistor amplifiers, typically; much less is common in class-AB vacuum-tube amplifiers). It is typically much more efficient than class A.


title: Power amplifier classes

text: A vacuum tube amplifier design will sometimes have an additional suffix number for the class, for example, class B1. A suffix 1 indicates that grid current does not flow during any part of the input waveform, where a suffix 2 indicates grid current flows for part of the input waveform. This distinction affects the design of the driver stages for the amplifier. Suffix numbers are not used for semiconductor amplifiers.


title: Power amplifier classes

text: In a class-C amplifier, less than 50% of the input signal is used (conduction angle Θ < 180°). Distortion is high and practical use requires a tuned circuit as load. Efficiency can reach 80% in radio-frequency applications.


title: Power amplifier classes

text: The usual application for class-C amplifiers is in RF transmitters operating at a single fixed carrier frequency, where the distortion is controlled by a tuned load on the amplifier. The input signal is used to switch the active device, causing pulses of current to flow through a tuned circuit forming part of the load.


title: Power amplifier classes

text: The class-C amplifier has two modes of operation: tuned and untuned. The diagram shows a waveform from a simple class-C circuit without the tuned load. This is called untuned operation, and the analysis of the waveforms shows the massive distortion that appears in the signal. When the proper load (e.g., an inductive-capacitive filter plus a load resistor) is used, two things happen. The first is that the output's bias level is clamped with the average output voltage equal to the supply voltage. This is why tuned operation is sometimes called a "clamper". This restores the waveform to its proper shape, despite the amplifier having only a one-polarity supply. This is directly related to the second phenomenon: the waveform on the center frequency becomes less distorted. The residual distortion is dependent upon the bandwidth of the tuned load, with the center frequency seeing very little distortion, but greater attenuation the farther from the tuned frequency that the signal gets.


title: Power amplifier classes

text: The tuned circuit resonates at one frequency, the fixed carrier frequency, and so the unwanted frequencies are suppressed, and the wanted full signal (sine wave) is extracted by the tuned load. The signal bandwidth of the amplifier is limited by the Q-factor of the tuned circuit but this is not a serious limitation. Any residual harmonics can be removed using a further filter.


title: Power amplifier classes

text: In practical class-C amplifiers a tuned load is invariably used. In one common arrangement the resistor shown in the circuit above is replaced with a parallel-tuned circuit consisting of an inductor and capacitor in parallel, whose components are chosen to resonate at the frequency of the input signal. Power can be coupled to a load by transformer action with a secondary coil wound on the inductor. The average voltage at the collector is then equal to the supply voltage, and the signal voltage appearing across the tuned circuit varies from near zero to near twice the supply voltage during the RF cycle. The input circuit is biased so that the active element (e.g., transistor) conducts for only a fraction of the RF cycle, usually one-third (120 degrees) or less.


title: Power amplifier classes

text: The active element conducts only while the collector voltage is passing through its minimum. By this means, power dissipation in the active device is minimised, and efficiency increased. Ideally, the active element would pass only an instantaneous current pulse while the voltage across it is zero: it then dissipates no power and 100% efficiency is achieved. However practical devices have a limit to the peak current they can pass, and the pulse must therefore be widened, to around 120 degrees, to obtain a reasonable amount of power, and the efficiency is then 60–70%.


title: Power amplifier classes

text: Class-D amplifiers use some form of pulse-width modulation to control the output devices. The conduction angle of each device is no longer related directly to the input signal but instead varies in pulse width.


title: Power amplifier classes

text: In the class-D amplifier the active devices (transistors) function as electronic switches instead of linear gain devices; they are either on or off. The analog signal is converted to a stream of pulses that represents the signal by pulse-width modulation, pulse-density modulation, delta-sigma modulation or a related modulation technique before being applied to the amplifier. The time average power value of the pulses is directly proportional to the analog signal, so after amplification the signal can be converted back to an analog signal by a passive low-pass filter.