title: Denavit–Hartenberg parameters

text: In mechanical engineering, the Denavit–Hartenberg parameters (also called DH parameters) are the four parameters associated with a particular convention for attaching reference frames to the links of a spatial kinematic chain, or robot manipulator.


title: Denavit–Hartenberg parameters

text: Jacques Denavit and Richard Hartenberg introduced this convention in 1955 in order to standardize the coordinate frames for spatial linkages.


title: Denavit–Hartenberg parameters

text: While many conventions for attaching reference frames have been developed, the Denavit–Hartenberg convention remains a popular approach.


title: Denavit–Hartenberg parameters

text: A commonly used convention for selecting frames of reference in robotics applications is the Denavit and Hartenberg (D–H) convention which was introduced by Jacques Denavit and Richard S. Hartenberg. In this convention, coordinate frames are attached to the joints between two links such that one transformation is associated with the joint, , and the second is associated with the link . The coordinate transformations along a serial robot consisting of links form the kinematics equations of the robot,


title: Denavit–Hartenberg parameters

text: In order to determine the coordinate transformations and , the joints connecting the links are modeled as either hinged or sliding joints, each of which have a unique line in space that forms the joint axis and define the relative movement of the two links. A typical serial robot is characterized by a sequence of six lines , one for each joint in the robot. For each sequence of lines and , there is a common normal line . The system of six joint axes and five common normal lines form the kinematic skeleton of the typical six degree of freedom serial robot. Denavit and Hartenberg introduced the convention that z-coordinate axes are assigned to the joint axes and x-coordinate axes are assigned to the common normals .


title: Denavit–Hartenberg parameters

text: This convention allows the definition of the movement of links around a common joint axis by the screw displacement,


title: Denavit–Hartenberg parameters

text: where is the rotation around and is the slide along the -axis—either of the parameters can be constants depending on the structure of the robot. Under this convention the dimensions of each link in the serial chain are defined by the screw displacement around the common normal from the joint to , which is given by


title: Denavit–Hartenberg parameters

text: where and define the physical dimensions of the link in terms of the angle measured around and distance measured along the X axis.


title: Denavit–Hartenberg parameters

text: There is some choice in frame layout as to whether the previous axis or the next points along the common normal. The latter system allows branching chains more efficiently, as multiple frames can all point away from their common ancestor, but in the alternative layout the ancestor can only point toward one successor. Thus the commonly used notation places each down-chain axis collinear with the common normal, yielding the transformation calculations shown below.


title: Denavit–Hartenberg parameters

text: It is common to separate a screw displacement into product of a pure translation along a line and a pure rotation about the line, so that


title: Denavit–Hartenberg parameters

text: Using this notation, each link can be described by a coordinate transformation from the concurrent coordinate system to the previous coordinate system.


title: Denavit–Hartenberg parameters

text: Note that this is the product of two screw displacements, The matrices associated with these operations are:


title: Denavit–Hartenberg parameters

text: where "R" is the 3×3 submatrix describing rotation and "T" is the 3×1 submatrix describing translation.


title: Denavit–Hartenberg parameters

text: In some books, the order of transformation for a pair of consecutive rotation and translation (such as formula_13and formula_14) is replaced. However, because matrix multiplication order for such pair does not matter, the result is the same. For example: formula_15.


title: Denavit–Hartenberg parameters

text: The Denavit and Hartenberg notation gives a standard (distal) methodology to write the kinematic equations of a manipulator. This is especially useful for serial manipulators where a matrix is used to represent the pose (position and orientation) of one body with respect to another.


title: Denavit–Hartenberg parameters

text: The position of body formula_16 with respect to formula_17 may be represented by a position matrix indicated with the symbol formula_18 or formula_19


title: Denavit–Hartenberg parameters

text: orientation of the two bodies, and the upper right formula_26 represents their relative position or more specifically the body position in frame "n" − 1 represented with element of frame "n".


title: Denavit–Hartenberg parameters

text: The position of body formula_27 with respect to body formula_28 can be obtained as the product of the matrices representing the pose of formula_29 with respect of formula_28 and that of formula_27 with respect of formula_29


title: Denavit–Hartenberg parameters

text: where formula_35 is both the transpose and the inverse of the orthogonal matrix formula_36, i.e. formula_37.


title: Denavit–Hartenberg parameters

text: The velocity of body formula_28 with respect to body formula_29 can be represented in frame formula_27 by the matrix


title: Denavit–Hartenberg parameters

text: where formula_42 is the angular velocity of body formula_43 with respect to body formula_44 and all the components are expressed in frame formula_45; formula_46 is the velocity of one point of body formula_43 with respect to body formula_48 (the pole). The pole is the point of formula_43 passing through the origin of frame formula_28.


title: Denavit–Hartenberg parameters

text: The acceleration matrix can be defined as the sum of the time derivative of the velocity plus the velocity squared


title: Denavit–Hartenberg parameters

text: The velocity and the acceleration in frame formula_44 of a point of body formula_43 can be evaluated as


title: Denavit–Hartenberg parameters

text: in other words the absolute velocity is the sum of the parent velocity plus the relative velocity; for the acceleration the Coriolis' term is also present.


title: Denavit–Hartenberg parameters

text: The components of velocity and acceleration matrices are expressed in an arbitrary frame formula_27 and transform from one frame to another by the following rule


title: Denavit–Hartenberg parameters

text: For the dynamics three further matrices are necessary to describe the inertia formula_63, the linear and angular momentum formula_64, and the forces and torques formula_65 applied to a body.


title: Denavit–Hartenberg parameters

text: where formula_68 is the mass, formula_69 represent the position of the center of mass, and the terms formula_70 represent inertia and are defined as


title: Denavit–Hartenberg parameters

text: All the matrices are represented with the vector components in a certain frame formula_27. Transformation of the components from frame formula_45 to frame formula_83 follows the rule


title: Denavit–Hartenberg parameters

text: The first of these equations express the Newton's law and is the equivalent of the vector equation formula_87 (force equal mass times acceleration) plus formula_88 (angular acceleration in function of inertia and angular velocity); the second equation permits the evaluation of the linear and angular momentum when velocity and inertia are known.


title: Denavit–Hartenberg parameters

text: Some books such as "Introduction to Robotics: Mechanics and Control (3rd Edition)" use modified (proximal) DH parameters. The difference between the classic (distal) DH parameters and the modified DH parameters are the locations of the coordinates system attachment to the links and the order of the performed transformations.


title: Denavit–Hartenberg parameters

text: Compared with the classic DH parameters, the coordinates of frame formula_89 is put on axis "i" − 1, not the axis "i" in classic DH convention. The coordinates of formula_90 is put on the axis "i", not the axis "i" + 1 in classic DH convention.


title: Denavit–Hartenberg parameters

text: Another difference is that according to the modified convention, the transform matrix is given by the following order of operations:


title: Denavit–Hartenberg parameters

text: Note that some books (e.g.:) use formula_93 and formula_94 to indicate the length and twist of link "n" − 1 rather than link "n". As a consequence, formula_95 is formed only with parameters using the same subscript.


title: Denavit–Hartenberg parameters

text: In some books, the order of transformation for a pair of consecutive rotation and translation (such as formula_13and formula_14) is replaced. However, because matrix multiplication order for such pair does not matter, the result is the same. For example: formula_98.


title: East Asia Summit

text: The East Asia Summit (EAS) is a regional forum held annually by leaders of, initially, 16 countries in the East Asian, Southeast Asian, South Asian and Oceanian regions, based on the ASEAN Plus Six mechanism. Membership expanded to 18 countries including Russia and the United States at the Sixth EAS in 2011. Since its establishment, ASEAN has held the central role and leadership in the forum. EAS meetings are held after the annual ASEAN leaders' meetings, and plays an important role in the regional architecture of Asia-Pacific. The first summit was held in Kuala Lumpur, Malaysia on 14 December 2005.


title: East Asia Summit

text: The concept of an East Asia Grouping has significant history going back to an idea first promoted in 1991 by then Malaysian Prime Minister Mahathir Mohamad.


title: East Asia Summit

text: The final report in 2002 of the East Asian Study Group, established by the ASEAN Plus Three countries, was based on an EAS involving ASEAN Plus Three, therefore not involving Australia, New Zealand, or India. The EAS as proposed was to be an ASEAN-led development, with the summit to be linked to ASEAN summit meetings. However, the issue was to which countries beyond those in ASEAN the EAS was to be extended.


title: East Asia Summit

text: The decision to hold the EAS was reached during the 2004 ASEAN Plus Three summit and the initial 16 members determined at the ASEAN Plus Three Ministerial Meeting held in Laos at the end of July 2005.


title: East Asia Summit

text: Credit for advancing the forum during the 2004 ASEAN Plus Three summit has been attributed to Malaysia.


title: East Asia Summit

text: Prior to the first meeting there was significant discussion as to which countries should be represented. At the time there were difficulties in the relationship between the "Plus Three" members (i.e. Japan, China and South Korea) of ASEAN Plus Three, and the perception that India and Australia and to a lesser extent New Zealand were present to balance the growing China power all meant the first meeting's achievements were limited. Russia expressed early interest in EAS membership and attended the first EAS as an observer at the invitation of 2005 EAS host Malaysia.


title: East Asia Summit

text: The next EAS was to be held on 13 December 2006 in Metro Cebu, Philippines. After the confidence building of the inaugural EAS the 2006 EAS will help to define the future role of the EAS, its relationship with ASEAN Plus Three and the involvement of Russia in EAS. However, in the face of Tropical Typhoon Utor the summit was postponed until January 2007. It was rescheduled for 15 January 2007, approximately a month after the original scheduled date.


title: East Asia Summit

text: Internal ASEAN issues were significant for the next Summits. The issues of Myanmar (Burma), following the 2007 Burmese anti-government protests, and climate change were expected to be discussed at the Third EAS. Myanmar successfully blocked formal discussion of its internal affairs.


title: East Asia Summit

text: The Summit also agreed to the establishment of the Economic Research Institute for ASEAN and East Asia and to receive the final report on the Comprehensive Economic Partnership for East Asia at the Fourth EAS.


title: East Asia Summit

text: The outcomes are summarised in the Chairman's Statement of the 3rd East Asia Summit Singapore, 21 November 2007.


title: East Asia Summit

text: The Fourth EAS was significantly delayed and its location changed a number of times due to internal tensions in Thailand, the host nation. In the lead up to the summit there were several border clashes between Thailand and Cambodia. The summit however is said to be used as an opportunity for discussions on the sidelines between the respective nation's leaders. The summit was cancelled following protesters taking over the summit's venue on the day of the summit. It was rescheduled and held on 25 October 2009. The summit adopted statements on disaster relief and the Nalanda University.


title: East Asia Summit

text: After a period of review, the Summit grew from 16 to 18 nations by adding the United States and Russia to the Summit. Initially represented by their Foreign Ministers at the Fifth EAS, the two new members were invited to formally join with the Sixth EAS. Tensions between the members of the Summit continued to impede the members developing a more ambitious program.


title: East Asia Summit

text: At the Second EAS the EAS members signed the Cebu Declaration on East Asian Energy Security, a declaration on energy security and biofuels, containing a statement for members to prepare non-binding targets.


title: East Asia Summit

text: As to trade and regional integration the following was noted in the Chair's report for the Second EAS:


title: East Asia Summit

text: 12. We welcomed ASEAN's efforts towards further integration and community building, and reaffirmed our resolve to work closely together in narrowing development gaps in our region. We reiterated our support for ASEAN's role as the driving force for economic integration in this region. To deepen integration, we agreed to launch a Track To study on a Comprehensive Economic Partnership for East Asia (CEPEA) among EAS participants. We tasked the ASEAN Secretariat to prepare a time frame for the study and to invite all our countries to nominate their respective participants in it.


title: East Asia Summit

text: The reality appears however that movement towards such a relationship is a long way-off. Lee Kuan Yew has compared the relationship between Southeast Asia and India with that of the European Community and Turkey, and has suggested that a free-trade area involving Southeast Asia and India is 30 to 50 years away.


title: East Asia Summit

text: The members of EAS agreed to study the Japanese proposed Comprehensive Economic Partnership in East Asia (CEPEA). The Track Two report on CEPEA is due to be completed in mid-2008 and at the Third EAS it was agreed this would be considered at the Fourth EAS.


title: East Asia Summit

text: As noted above the Second EAS welcomed the Economic Research Institute for ASEAN and East Asia (ERIA). It was subsequently announced that the ERIA would be established in November 2007 and confirmed at the Third EAS.


title: East Asia Summit

text: The Declaration of the Fifth Anniversary of the East Asia Summit issued at the Fifth EAS provided the Summit declared:


title: East Asia Summit

text: 3. To redouble efforts to move progress and cooperation in the EAS further forward, including in the priority areas and in the promotion of regional integration through supporting the realisation of the ASEAN Community and such initiatives as the ASEAN Plus FTAs and other existing wider regional economic integration efforts including studies on East Asia Free Trade Area (EAFTA) and Comprehensive Economic Partnership in East Asia (CEPEA).


title: East Asia Summit

text: After the EAS was established the issue arose of whether any future East Asia Community would arise from the EAS or ASEAN Plus Three. Prior to the creation of the EAS it appeared that ASEAN Plus Three would take the role of community building in East Asia.


title: East Asia Summit

text: Malaysia felt that it was still the case that the role of the community building fell to ASEAN Plus Three shortly before the second EAS despite "confusion". China apparently agreed whereas Japan and India felt the EAS should be the focus of the East Asian Community.


title: East Asia Summit

text: After the first EAS the feasibility of EAS to have a community building role was questioned with Ong Keng Yong, the secretary-general of ASEAN being quoted as describing the EAS as little more than a "brainstorming forum".


title: East Asia Summit

text: Nevertheless, the Chairman’s Press Statement for the Seventh ASEAN Plus Three Foreign Ministers’ Meeting Kuala Lumpur, 26 July 2006 said


title: East Asia Summit

text: 25. The Ministers welcomed the convening of the East Asia Summit as a forum for dialogue on broad strategic, political and economic issues of common interest with the aim of promoting peace, stability and economic prosperity in East Asia. In this respect, they recognized that the East Asia Summit could make a significant contribution to the achievement of the long-term goal of establishing an East Asian community.


title: East Asia Summit

text: It appeared that over time following the first EAS the focus was less on whether the EAS has a role in community building to what the role and whether it was secondary to ASEAN Plus Three. By mid-2006 the Chinese news site Xinhua Net suggested the community would arise through a two-phase process with ASEAN Plus Three as the first phase and the EAS as the second phase. The China-India joint declaration of 21 November 2006 linked, at paragraph 43, the EAS with the East Asian Community process.


title: East Asia Summit

text: The concentric circle model of the community process with ASEAN at the centre, ASEAN Plus Three at the next band and the East Asia Summit at the outer band is supported by the Second Joint Statement on East Asia Cooperation Building on the Foundations of ASEAN Plus Three Cooperation which said:


title: East Asia Summit

text: A. Defining the Objectives and Roles of the ASEAN Plus Three Cooperation in the Emerging Regional Architecture


title: East Asia Summit

text: 1. We reaffirmed that the ASEAN Plus Three Process would remain as the main vehicle towards the long-term goal of building an East Asian community, with ASEAN as the driving force.


title: East Asia Summit

text: 3. We recognised and supported the mutually reinforcing and complementary roles of the ASEAN Plus Three process and such regional fora as EAS, ARF, APEC and ASEM to promote East Asian community building.


title: East Asia Summit

text: 4. We reiterated that East Asian integration is an open, transparent, inclusive, and forward-looking process for mutual benefits and support internationally shared values to achieve peace, stability, democracy and prosperity in the region. Guided by the vision for durable peace and shared prosperity in East Asia and beyond, we will stand guided by new economic flows, evolving strategic interactions and the belief to continue to engage all interested countries and organisations towards the realisation of an open regional architecture capable of adapting to changes and new dynamism.


title: East Asia Summit

text: On any view, community building is not a short-term project. However, after the second EAS, the Indian Prime Minister Manmohan Singh was confident that the EAS would lead to an East Asia Community. China had also apparently accepted this was the case.


title: East Asia Summit

text: If achieved the Comprehensive Economic Partnership for East Asia (CEPEA) would be a tangible first step in the community building process. The second EAS seems to have increased confidence in CEPEA but is still only a proposal.


title: East Asia Summit

text: It has been suggested that as the EAS consists of an "anti-region" the prospects of it forming a community are less than likely.


title: East Asia Summit

text: The relationship between the EAS on one hand and ASEAN Plus Three on the other is still not clear. As discussed above, some countries are more supportive of the narrower ASEAN Plus Three grouping whereas others support the broader, more inclusive EAS. ASEAN Plus Three, which has been meeting since December 1997 has a history, including the Chiang Mai Initiative which appears to have led to the development of the Asian Monetary Unit. This may be significant for those advocating a broader role for EAS in the future.


title: East Asia Summit

text: The tension between the groupings extends to the respective members' intentions towards future Free Trade Agreements with China and South Korea focused on ASEAN Plus Three and Japan on the broader EAS members.


title: East Asia Summit

text: The 1997 Asian financial crisis had demonstrated the need for regional groupings and initiatives. It was during this time ASEAN Plus Three had commenced and it was also during this time that the East Asian caucus was being discussed.


title: East Asia Summit

text: The EAS is just one regional grouping and some members down play its significance, the former Australian Prime Minister John Howard has stated that the EAS was secondary as a regional summit to APEC which has on his view a premier role. Not all members of the EAS, notably India, are members of APEC. However, as the EAS meetings are scheduled with the ASEAN Plus Three meetings (they both follow the annual ASEAN meetings) and all members of ASEAN Plus Three are members of EAS the ability of the two forums to remain relevant given the existence of the other remains in question. China has stated its preference for both EAS and ASEAN Plus Three to exist side by side.


title: East Asia Summit

text: The relationship between APEC, ASEAN Plus Three and the EAS remained unresolved heading into the 2007 APEC meeting. Following the meeting the then Malaysian Prime Minister Abdullah Ahmad Badawi described ASEAN Plus Three as the primary vehicle and implied APEC was the lesser of the three. At the same time a Malaysian commentator writing in a Singaporean newspaper described concentric circles for the three with ASEAN Plus Three at the centre and APEC at the outer, also suggested the Nikai Initiative, with its regional OECD like plans, might overtaking the remaining role for APEC.


title: East Asia Summit

text: Russia participated in the first EAS as an observer at the invitation of 2005 host Malaysia and requested to become a member. Its request to become a future member received support from China and India.


title: East Asia Summit

text: The membership of EAS was to be considered by ASEAN on a case-by-case basis. ASEAN decided to freeze new "membership" of EAS for the second and third summits.


title: East Asia Summit

text: The status of potential future members was discussed in the Chairman's Statement of the 16th ASEAN Summit (9 April 2010) in these terms:


title: East Asia Summit

text: 43. We recognized and supported the mutually reinforcing roles of the ASEAN+3 process, the East Asia Summit (EAS), and such regional forums as the ASEAN Regional Forum (ARF), to promote the East Asian cooperation and dialogue towards the building of a community in East Asia. In this connection, we encouraged Russia and the US to deepen their engagement in an evolving regional architecture, including the possibility of their involvement with the EAS through appropriate modalities, taking into account the Leaders-led, open and inclusive nature of the EAS.


title: East Asia Summit

text: Japan and India supported inclusion of the United States and Russia prior to their invitation to join the East Asia Summit.


title: East Asia Summit

text: US President Barack Obama declared his country "an Asia Pacific nation" during his first year in office. Subsequently, US Secretary of State Hillary Clinton attended the Fifth EAS in October 2010 and President Obama attended the Sixth EAS in November 2011.


title: East Asia Summit

text: In April and May 2010 it was discussed that the roles for Russia and the United States may be to create a new grouping "ASEAN + 8" including the East Asia Summit members together with the United States and Russia. ASEAN + 8 may not meet as regularly as the East Asia Summit due to the logistical difficulties in the United States President committing to an annual Asian meeting. Such a meeting could be held every two to three years to coincide with the APEC meeting occurring in Asia.


title: East Asia Summit

text: East Timor is a candidate ASEAN member seeking membership within five years (from 2006) and Papua New Guinea has shown intention to join; presumably new members of ASEAN would also join the EAS.


title: East Asia Summit

text: Over several years, especially shortly the commencement of the summits, other countries have been connected with the EAS.


title: East Asia Summit

text: In 2006, Pakistan and Mongolia were proposed as future members by Malaysia. Mongolia was mentioned again by Vietnam, the then chair, in 2010.


title: East Asia Summit

text: In 2017, Sri Lanka and Maldives were proposed to be possible members of East Asia Summit. Prime Minister of Canada Justin Trudeau attended as guest. He had arrived directly from the APEC 2017 summit held in Da Nang, Vietnam.


title: Killing of Faith Hedgepeth

text: The body of Faith Hedgepeth (born September 26, 1992), an undergraduate student in her third year at the University of North Carolina at Chapel Hill (UNC), was found in her apartment by a friend on the morning of September 7, 2012. She had been beaten over the head with a blunt instrument, later found to be an empty liquor bottle, and evidence of semen and male DNA was present at the crime scene. The last time she was known for certain to be alive was much earlier that morning, when she went to bed after returning from a local nightclub with her roommate.


title: Killing of Faith Hedgepeth

text: Police have recovered considerable forensic evidence in the case, but so far it has served to eliminate one likely suspect, a former boyfriend of her roommate who reportedly expressed anger and resentment toward Hedgepeth, even supposedly threatening to kill her if he could not reunite with her roommate. His DNA, however, did not match that left at the scene. A note left at the scene, suggesting the writer was jealous, is also believed to have been written by the killer; it was among a large group of documents released by police two years after the crime, following a court action brought by several local media outlets.


title: Killing of Faith Hedgepeth

text: Four years after the killing, a Virginia DNA testing company prepared and released, at police's behest, an image showing what the suspect might look like based on his genetic phenotype. A voicemail possibly accidentally recorded by Hedgepeth may also capture some of the events that led to her death.


title: Killing of Faith Hedgepeth

text: In September 2021, the Chapel Hill Police Department announced an arrest in the case. The suspect, not initially considered, had been linked to the case through DNA evidence after a drunken-driving arrest the month before.


title: Killing of Faith Hedgepeth

text: A member of the Haliwa-Saponi Native American tribe recognized by the state of North Carolina, Faith Hedgepeth was born in 1992 in Warren County, part of the tribe's traditional territory. Her parents divorced within a year of her birth, and she was raised by her mother, with help from an older sister, in Hollister and Warrenton. Connie Hedgepeth named her second daughter Faith because she believed that was what she needed to raise a fourth child when she already had two sons, a daughter and a husband with a drug problem.


title: Killing of Faith Hedgepeth

text: In high school, Hedgepeth was an honor student, a cheerleader and a member of many extracurricular clubs and organizations. She did well enough academically to earn a Gates Millennium Scholarship to attend the University of North Carolina at Chapel Hill. Her father had attended UNC-CH as well, but had dropped out. She hoped to be the first in her family to graduate from college. After undergraduate studies, she was considering further studies to become either a pediatrician or teacher.


title: Killing of Faith Hedgepeth

text: Her first two years at the university went well for her, although she took the spring 2012 semester off. She remained in the Chapel Hill area over the summer, living in an off-campus apartment at the Hawthorne at the View complex between Chapel Hill and Durham, on the line between Durham and Orange counties, during the month of August. She planned to move to another apartment after her financial aid for the fall semester was made available to her. She shared the apartment with Karena Rosario, with whom she had been friends since freshman year, and Rosario's boyfriend, Eriq Takoy Jones.


title: Killing of Faith Hedgepeth

text: The relationship between Jones and Rosario had been marked by domestic violence, and eventually she ended it and he moved out. However, he had in early July 2012 twice attempted to break into the apartment, even after Rosario changed the locks. Hedgepeth eventually drove Rosario to court to get a protective order that required Jones to stay away from the apartment. Jones reportedly resented Hedgepeth's influence over his former girlfriend, and at one point reportedly threatened during a phone conversation with Hedgepeth to kill her if he could not get back together with Rosario.


title: Killing of Faith Hedgepeth

text: The evening of September 6, 2012, a Thursday, began at 5:45 p.m. with Hedgepeth attending a rush event for the campus chapter of Alpha Pi Omega, a historically Native American sorority she hoped to join. At 7:15 she left, saying she had to work on a paper she was writing about the history of her tribe. She and Rosario went to the university's Davis Library to study together at 8 p.m. Between 8:30 and 9 she exchanged texts with her father about her hopes to join the sorority.


title: Killing of Faith Hedgepeth

text: Hedgepeth left Rosario there briefly and returned around 11:30, after which they returned to their apartment together, arriving there around midnight. A half-hour later they left again, heading for The Thrill, a now-closed nightclub in downtown Chapel Hill which admitted customers under the legal drinking age of 21 to dance. The two young women arrived at The Thrill around 12:40 a.m. After almost an hour and a half of dancing, Rosario told police later that she was having an upset stomach and wanted to leave. Security cameras at the club show her and Hedgepeth leaving at 2:06 a.m.; it is the last visual record of her presence anywhere before the killing.


title: Killing of Faith Hedgepeth

text: By 3 a.m. Hedgepeth and Rosario had returned to their apartment. A woman who lived below the two and was awake watching television said that she heard three thumping noises, which she described as similar to a heavy bag being dropped or furniture being overturned, shortly afterward. Hedgepeth's Facebook page was also accessed around the same time.


title: Killing of Faith Hedgepeth

text: At 3:40 a.m., a text was sent from Hedgepeth's phone to that of Brandon Edwards, a former boyfriend of Rosario, saying "Hey b. Can you come over here please. Rosario needs you more aha. You know. Please let her know you care." Three minutes later, another text was sent from Hedgepeth's phone to Edwards' with the single word "than," believed to be a correction for the "aha" in the previous text. That was the last evidence of activity from her phone. At 4:16 a.m., Edwards sent a return text asking who had sent the previous text.


title: Killing of Faith Hedgepeth

text: Rosario's phone records show she was also trying to call Edwards around the same time. He did not answer, and when he did not she tried to call Jordan McCrary, a UNC-CH soccer player she knew. At 4:25 a.m., she left the apartment to get in McCrary's car. At that time, Rosario said later, she believed Hedgepeth was asleep in her room, and left the apartment's door unlocked.


title: Killing of Faith Hedgepeth

text: McCrary drove Rosario to the home of another acquaintance on West Longview Street in Chapel Hill. She put the time of her arrival there at around 4:30 a.m. After spending the rest of the night and the early morning there, a short time after 10:30 she began trying to arrange a ride home. After attempting to reach Hedgepeth, who did not answer, Rosario instead called another friend, Marisol Rangel, who came and took her back to her apartment.


title: Killing of Faith Hedgepeth

text: When they arrived there, shortly before 11 a.m., they entered and called for Hedgepeth, who did not respond. In her bedroom, they found her bloodied body, wrapped in a quilt, partially nude. They immediately dialed 9-1-1 and informed police.


title: Killing of Faith Hedgepeth

text: Details of the investigation were not discussed publicly at first, a deviation from the Chapel Hill police's usual practice. The town obtained a court order sealing all records as they were collected. Police collected semen from the scene and used it to develop a DNA profile; it reportedly was consistent with male DNA found elsewhere in the apartment. The autopsy determined that Hedgepeth had died from blunt force trauma to the head, likely a result of being hit by an empty rum bottle in the apartment.


title: Killing of Faith Hedgepeth

text: Jones seemed to be a very strong suspect from the beginning. Police learned of his history of domestic violence and his threat against Hedgepeth. They also found that the night before, around 6 p.m., he had texted an acquaintance asking for forgiveness "for what I am about to do" and then posted the same message on his Twitter feed. Three days later, he changed the banner on his Facebook page to read "Dear Lord, Forgive me for all of my sins and the sins I may commit today. Protect me from the girls who don't deserve me and the ones who wish me dead today."


title: Killing of Faith Hedgepeth

text: Police sought a DNA sample from Jones, whom they considered a person of interest. After some initial resistance, he complied. His DNA did not match the sample from the apartment, and they excluded him as a suspect. DNA from Edwards and many other men whom police found had been at The Thrill during the same time as Rosario and Hedgepeth was also tested, with the same result.


title: Killing of Faith Hedgepeth

text: Within days the university's board of trustees, the local Crime Stoppers chapter, the Haliwa-Saponi tribe, and the apartment complex had offered a combined $29,000 in reward money for information leading to an arrest. Police hoped the reward money would lead to a quick resolution of the case, as their resources were limited. In the 2008 murder of Eve Carson, who at the time was UNC-CH's undergraduate student body president, a $25,000 reward had led to the killers' arrest. Two months later, the office of governor Bev Perdue added another $10,000 to the reward for Hedgepeth's killer.


title: Killing of Faith Hedgepeth

text: In November, "The Daily Tar Heel", UNC-CH's student newspaper, petitioned the judge who had ordered the investigation records sealed to release an early search warrant in the case. Instead, the judge ordered it resealed for another 45 days. At that time, the Chapel Hill police had not even released Hedgepeth's cause of death, although her parents told the media that their daughter's death certificate said she had been beaten.


title: Killing of Faith Hedgepeth

text: Police announced in January that the DNA from the scene had come back as belonging to a male. From the crime scene and other evidence the Federal Bureau of Investigation (FBI) had developed a profile of the man. They said it was likely that he had lived near Hedgepeth in the past, had expressed an interest in her and his behavior may have changed since the crime, including showing an unusual interest in the case. Notwithstanding this release of information, the town successfully petitioned the court to keep the warrants under seal, saying that phase of the investigation was still not complete; in May 2013 the court extended the seal another 60 days.


title: Killing of Faith Hedgepeth

text: In September 2013, a year after the killing, Chapel Hill police formally requested the assistance of the North Carolina State Bureau of Investigation, which had provided some help earlier in the investigation, with the case. "We're working the case hard, and we've used all the possible resources," said Chief Chris Blue. However, he would not share any more information about the case.


title: Killing of Faith Hedgepeth

text: Two months later, the "Tar Heel" noted that the Hedgepeth case remained open, along with the death case of David Shannon, a UNC-CH freshman whose body had been found on the grounds of a Carrboro cement plant the previous October 27 (while he had died from a fall, the autopsy found he was severely intoxicated, and the Carrboro police suspected hazing and believed there might be other students who could tell them more about the circumstances of Shannon's death). In Hedgepeth's case, there had been no new information about a possible suspect since January. Yet the case records remained under court-ordered seal.


title: Killing of Faith Hedgepeth

text: In March 2014 the "Tar Heel" was joined by the Raleigh "News & Observer" and Capitol Broadcasting Company, which owns three television and radio stations in the Research Triangle area, in opposing the district attorney's motion to extend the seal another 60 days. They argued that the order was not justified by a compelling interest on the state's part, and that some of the orders had been issued before the records covered by them had been created, meaning the argument for sealing them was speculative. During a hearing on the motion, the district attorney filed a more specific accounting of what investigative work had been done, allowing the media to report for the first time on what police had searched in the immediate aftermath of the crime. "Eighteen months goes by and no one's been charged and no one's been arrested," said a lawyer for the "Tar Heel". "The public has the right to assume the trail has gone cold, or it's not being investigated in a diligent manner." In response, the district attorney's office argued that releasing the detailed records at that point would definitely hinder the investigation, and the records remained under seal.


title: Killing of Faith Hedgepeth

text: The following month, Chelsea Dulaney, a reporter who had originally covered the case at the "Tar Heel", wrote an article on the "Atavist" platform taking a skeptical look at the sealing of the case. She speculated that the seal's real purpose was to conceal early missteps by the Chapel Hill police, who might also not have been competent enough to handle the investigation by themselves. The town's court filings, she noted, revealed that after the first two months of the investigation no new search warrants had been sought. "We have to ask, how hot is it?" asked one of the lawyers representing the media.


title: Killing of Faith Hedgepeth

text: Dulaney talked to the residents of the apartments at Hawthorne at the View who lived near Hedgepeth and Rosario. They told her that during the preceding summer, they strongly suspected the domestic violence later reported between Rosario and Jones; they thought the police presence on the day the body was found was related to that until they learned otherwise.


title: Killing of Faith Hedgepeth

text: Two of the neighbors told Dulaney that while the police sealed off the four-unit block where Hedgepeth and Rosario lived with crime scene tape, they only searched the women's apartment and not any of the others in it. Nor did they search the woods behind the apartments, and they only returned later to search one other apartment in the complex. They did not seem to canvass the area either, never knocking on doors and asking residents what they might have seen. The police also left Hedgepeth's car unsecured while they searched the apartments.


title: Killing of Faith Hedgepeth

text: When the State Bureau of Investigation officers began investigating the case late in 2013, they also interviewed residents of Hawthorne at the View. One resident who spoke to Dulaney said it was clear to her that the SBI investigators were better trained than their Chapel Hill counterparts had been. The agent who interviewed her asked questions that elicited more useful information from her, she recalled.


title: Killing of Faith Hedgepeth

text: In downtown Chapel Hill, Dulaney talked to the owner of a towing service who had the contract for the Thrill's parking lot. He had set up a system of security cameras to monitor activity in the club's parking lot that might have possibly recorded anything that happened outside of the club involving Hedgepeth and Rosario while they were there that morning, or after they left. The police did not ask to see it until shortly before Dulaney wrote the article, almost 19 months after the crime. By that time, he told her, any footage from that night had been long since recorded over.


title: Killing of Faith Hedgepeth

text: The court ordered the records unsealed in July 2014. Media organizations were able to review and report on the search warrant applications and the investigative notes that had supported them, with most names redacted, for not only the residences and cars but Hedgepeth's phone, computer, Facebook records and bank account. Also released was the transcript of Rosario's 9-1-1 call, and the content of the early-morning text messages as well as the timeline of Rosario and Hedgepeth's actions the night before the body was found.


title: Killing of Faith Hedgepeth

text: In September 2014, almost two years after Hedgepeth's death, the autopsy report was released. It confirmed what was on her death certificate, that she had died of blunt force trauma to the head. She had numerous cuts and bruises as well as blood under her fingernails, suggesting she had struggled with her killer. The DNA taken from the semen was matched to DNA elsewhere at the scene.


title: Killing of Faith Hedgepeth

text: The released records included the recording of Rosario's 9-1-1 call and two pieces of evidence that were seen as potentially helpful in narrowing down the killer's identity. The DNA profile was also used later to generate an image of the potential suspect. "Investigators have excellent evidence in this case," Chief Blue said when the documents were released. "This is not a cold case. It has been and remains an active investigation."


title: Killing of Faith Hedgepeth

text: "News & Observer" reporter Tom Gasparoli, who covered the case extensively for his newspaper, has also devoted most of his own blog to pondering the evidence and keeping the case alive. To him, Rosario's call raised many questions. "To me, the whole call reeks of unusual," he wrote in 2017 on the case's fifth anniversary.


title: Killing of Faith Hedgepeth

text: Gasparoli raised the possibility that Rosario's friend Marisol Rangel, whose voice sounds to him more like the constantly sobbing caller, was the real caller, only later identifying herself as Rosario after repeated requests from the dispatcher for her name. And if it was Rosario, she never mentions that Rangel accompanied her to the apartment. The caller also does not mention Hedgepeth's name in a call that lasts nearly eight minutes, only describing the body she has come upon as "her friend."


title: Killing of Faith Hedgepeth

text: And why, Gasparoli asked, does the caller seem reluctant to touch Hedgepeth's body despite repeated pleas from the dispatcher to at least see if she is still breathing? If Rosario was not able to bring herself to do so, could she not have asked Rangel to do so? "I have often thought," Gaparoli wrote,"[that] if it was [Rosario], that she didn't call 9-1-1 the moment she first saw [Hedgepeth]."


title: Killing of Faith Hedgepeth

text: It was sloppily written in ballpoint pen on what was determined to be the torn-off bottom of a white paper bag of the type commonly used for carry-out food. Police believe the bag may have come from Time-Out, a popular 24-hour restaurant in Chapel Hill that would have been the only place open at the time Hedgepeth and Rosario left The Thrill. It uses such bags and is a short distance away from the nightclub.


title: Killing of Faith Hedgepeth

text: Investigators have not said whether they have had the handwriting analyzed. The website "Crime Watch Daily" had an expert, Peggy Walla, look at photos of the note. She noted that it was clean of the blood reportedly found splattered all over the room, suggesting it was written either away from the crime scene or beforehand. The writer may have been using their non-dominant hand in an attempt to disguise their handwriting. Walla believes the writer was particularly agitated, likely to the point of homicidal rage, by being called "stupid."


title: Killing of Faith Hedgepeth

text: In his post marking the fifth anniversary of the case, Gasparoli said a law enforcement source he talked to about the case refused to comment on whether the note was "odd" even as the source answered other questions. He elaborates that the words may have been intended to be read in a different order, producing wording that makes more sense ("I'm not jealous ... stupid bitch," for instance). In addition, he theorizes that more than one writer may have been involved, or that not all of it may have been written at the same time.


title: Killing of Faith Hedgepeth

text: The word ""STUPID"" especially looks to Gasparoli as if it might have been written separately from the other words, as it is written much more clearly and off to the side. The swash extending leftward from the counter on the ""P"" in ""STUPID"" struck him as unusually distinctive. "[It] looks quite different, much more precise than any other letter in the note," he says. It seems to Gasparoli to suggest a female writer, or at least one calmer and more intelligent than the lettering elsewhere on the note.


title: Killing of Faith Hedgepeth

text: Gasparoli questioned in fact what purpose would be served by leaving it there. As a message to Hedgepeth, it made no sense to leave it next to her body if she was dead; if it was written by the killer or killers, it could have been particularly incriminating evidence and they had to be aware of that possibility. It looked to him, in fact, "[a]lmost as if it were a red herring ... left for some other reason than to reflect the real feelings of the killer(s). Left ... to confuse."


title: Killing of Faith Hedgepeth

text: A friend of Hedgepeth's shared with police a long conversation, perhaps inadvertently recorded, when Hedgepeth's phone pocket-dialed them on the night before the murder, that may have some bearing on the case. It consisted of a three-way conversation, three minutes long, between what sounds to be Hedgepeth and a male and female, with music in the background. It was timestamped at 1:23 a.m., when the night's timeline has Hedgepeth at The Thrill.


title: Killing of Faith Hedgepeth

text: It was mostly inaudible and of minimal evidentiary value until "Crime Watch Daily" hired audio expert Arlo West, who specializes in enhancing such recordings. He claimed he heard Hedgepeth crying for help while the female says "I think she's dying" and the male says "Do it anyhow" after a long discussion in which the female seems to get angrier. The male and female use the name "Eriq" and "Rosie" (which is Rosario's nickname) respectively. Hedgepeth's father is convinced what was recorded was of his daughter's death; West agrees.


title: Killing of Faith Hedgepeth

text: The website informed the Chapel Hill police of West's findings, and they agreed to consider West's enhanced version and evaluate it. However, due to the time of the message, they do not believe it to be a recording of the killing; the music in the background further suggests it was recorded at The Thrill. Several months later, they added that the metadata associated with the call reinforces this belief.


title: Killing of Faith Hedgepeth

text: West, for his part, cites a known software issue with phones like Hedgepeth's that resulted in inaccurate timestamps. He discounts the background sound as being music, since his analysis did not produce any sounds like percussion, a heavy bass or synthesizers. Further, he adds, there are none of the background sounds, like glasses clinking and others talking, that one would associate with a nightclub.


title: Killing of Faith Hedgepeth

text: On a September 23, 2016, episode of the ABC News program "20/20", Chapel Hill police released an image generated by Parabon NanoLabs, a genetic testing company in Reston, Virginia, of what the suspect who left the semen might look like based purely on the phenotype in his DNA profile. Parabon's president told ABC that Snapshot, the program his company used to create the image, "predicts eye color, hair color, skin color, freckling, face morphology and ancestry." The image included a chart listing the probability that the suspect had the traits he was assigned.


title: Killing of Faith Hedgepeth

text: According to the image, the suspect was "very strongly Native American and European mixed ancestry or Latino." Most of his genetic markers pointed to Mexican, Colombian and Iberian ancestry, with some other South American and African countries making up the balance. Parabon believed with over 80 percent confidence that the suspect would have a skin tone in the olive range, with very few freckles or none at all and black hair. It did not make any predictions as to his height and weight.


title: Killing of Faith Hedgepeth

text: Chapel Hill police have not said much about how the crime happened despite the September 2021 arrest. In the past they said they do not believe the killing was a mere crime of opportunity by a stranger, and instead it was committed by someone in her social group, likely someone who knew her through UNC-CH. They are certain the killer or killers knew Hedgepeth, and have interviewed 2,000 people, with DNA tests done on 750 of those. They mapped the relations of many of those interviewees with Hedgepeth and each other, and had reportedly narrowed a pool of a thousand possible suspects down to 10. "This is not a cold case. It's never been a cold case," Chief Blue told Gasparoli in 2016.


title: Killing of Faith Hedgepeth

text: A year later, Gasparoli said that he believed that the killer was "just outside" Hedgepeth's closest friends and acquaintances. "Good chance this person didn't know [Hedgepeth] or investigators would know who it was," he wrote. They may, however, have been acting out of anger at some grievance she caused to someone closer to her.


title: Killing of Faith Hedgepeth

text: Blue declined to answer Gasparoli's question at that time as to whether investigators believed more than one person had been involved. "It's a piece of the puzzle we do not have if we connect the direct physical evidence," Celisa Lehew, who took over the case as the department's new chief investigator in 2016, told the reporter regarding that theory. "There was some knowledge that two people lived there."


title: Killing of Faith Hedgepeth

text: Speculation has sometimes focused on Rosario, Hedgepeth's roommate at the time, due to her 9-1-1 call, the last texts sent from Hedgepeth's phone to her former boyfriend suggesting that "[Rosario] needs you more than you know," the woman addressed as "Rosie" on the voicemail conversation and her decision to leave the apartment unlocked with, she claims, a sleeping Hedgepeth inside, to go sleep somewhere else at 4:30 the morning of the killing. Although she has left North Carolina and said very little about the case since then, Gasparoli wrote in 2017 that he learned from his police sources that they still regularly speak with her, and she cooperates. "They do believe there is more Rosario can tell them," he says. "[It] sounds to me like [Rosario] has been in the crosshairs ... as a key figure who knows more than she says she knows."


title: Killing of Faith Hedgepeth

text: On September 16, 2021, the Chapel Hill Police Department arrested Miguel Salguero-Olivares, 28, of Durham, on a first-degree murder charge in Hedgepeth's death. He had not been a suspect originally, but was identified through DNA samples after he had been arrested on a drunken-driving charge in Wake County the preceding month. According to court documents released in January 2022, the DNA found at the scene and the palm print on the murder weapon match Salguero-Olivares. In a statement, the police asked the public to bear with them as they sorted the details out. "This story will take time to completely unfold", said Chief Blue.


title: Equestrian Statue of Marcus Aurelius

text: The Equestrian Statue of Marcus Aurelius (, ) is an ancient Roman equestrian statue on the Capitoline Hill, Rome, Italy. It is made of bronze and stands 4.24 m (13.9 ft) tall. Although the emperor is mounted, it exhibits many similarities to standing statues of Augustus. The original is on display in the Capitoline Museums, with the one now standing in the open air of the Piazza del Campidoglio being a replica made in 1981 when the original was taken down for restoration.


title: Equestrian Statue of Marcus Aurelius

text: The overall theme is one of power and divine grandeur—the emperor is over life-size and extends his hand in a gesture of adlocutio used by emperors when addressing their troops. Some historians assert that a conquered enemy was originally part of the sculpture (based on accounts from medieval times, including the "Mirabilia Urbis Romae", that suggest a small figure of a bound barbarian chieftain once cowered underneath the horse's front right leg). Such an image was meant to portray the Emperor as victorious and all-conquering. However, shown without weapons or armour, Marcus Aurelius seems to be a bringer of peace rather than a military hero, for this is how he saw himself and his reign.He is riding without the use of stirrups, which had not yet been introduced to the West. While the horse has been meticulously studied in order to be recreated for other artists' works, the saddle cloth was copied with the thought that it was part of the standard Roman uniform. The saddle cloth is actually Sarmatian in origin, suggesting that the horse is a Sarmatian horse and that the statue was created to honour the victory over the Sarmatians by Marcus Aurelius, after which he adopted "Sarmaticus" to his name.


title: Equestrian Statue of Marcus Aurelius

text: The statue was erected around 175 AD. Its original location is debated: the Roman Forum and Piazza Colonna (where the Column of Marcus Aurelius stands) have been proposed. However, it was noted that the site where it had originally stood had been converted into a vineyard during the early Middle Ages.


title: Equestrian Statue of Marcus Aurelius

text: Although there were many equestrian imperial statues, they rarely survived because it was the common practice to melt down bronze statues for reuse as material for coins or new sculptures in the late empire. Indeed, it is one of only two surviving bronze statues of a pre-Christian Roman emperor; the Regisole, destroyed after the French Revolution, may have been another. The equestrian Statue of Marcus Aurelius in Rome owes its preservation on the Campidoglio to the popular mis-identification of Marcus Aurelius, the philosopher-emperor, with Constantine the Great, the Christian emperor; indeed, more than 20 other bronze equestrian statues of various emperors and generals had been melted down since the end of the Imperial Roman era. It has been speculated that its misidentification stems from the prior existence of an equestrian statue of Constantine which had stood beside the Arch of Septimius Severus, and which had been most likely taken on the orders of the emperor Constans II during his visit to Rome in 663. With its removal, the people eventually mistakenly identified Marcus Aurelius's statue for Constantine's.


title: Equestrian Statue of Marcus Aurelius

text: In the medieval era it was one of the few Roman statues to remain on public view. In the 8th century it stood in the "Campus Lateranensis", to the east of the Lateran Palace in Rome, sitting on a pedestal that was later provided by Sixtus IV. Its placement next to the Lateran Palace was due the fact that this site used to contain the house of Marcus Aurelius's grandfather Marcus Annius Verus, which was where the Emperor's birth and early education took place. From here it was relocated in 1538, by order of Pope Paul III to remove it from the main traffic of the square. It was moved to the Piazza del Campidoglio (Capitoline Hill) during Michelangelo's redesign of the Hill. Though he disagreed with its central positioning, he designed a special pedestal for it. The original is on display in the Palazzo dei Conservatori of the Musei Capitolini, while a replica has replaced it in the square.


title: Equestrian Statue of Marcus Aurelius

text: On the night of November 29, 1849, at the inception of the revolutionary Roman Republic, a mass procession set up the Red-White-Green tricolore (now


title: Equestrian Statue of Marcus Aurelius

text: The statue is featured on the reverse of the aureus of Marcus Aurelius, struck in 174 AD. The statue is depicted on the reverse of the contemporary Italian €0.50 coin, designed by .


title: Equestrian Statue of Marcus Aurelius

text: The statue was formerly clad in gold. An old local myth says that the statue will turn gold again on the Judgement Day.


title: Equestrian Statue of Marcus Aurelius

text: Allegedly the equestrian statue of King George III of Great Britain which stood in New York City's Bowling Green until 1776 (when it was thrown down and the lead turned into musket balls for George Washington's army) was based upon the Equestrian Statue of Marcus Aurelius. Richard Westmacott modeled later statues of King George III on the "Equestrian Statue."


title: Equestrian Statue of Marcus Aurelius

text: Sculptor Jacques Saly modeled his 1768 Equestrian statue of Frederick V in Copenhagen, Denmark upon that of Marcus Aurelius.


title: Equestrian Statue of Marcus Aurelius

text: The Monument to Prince Józef Poniatowski in Warsaw by Bertel Thorvaldsen, from 1829, was based on this statue.


title: Equestrian Statue of Marcus Aurelius

text: Sculptor David Wynne visited Rome to see the statue, while producing his own equestrian statue, "The Messenger".


title: Equestrian Statue of Marcus Aurelius

text: In 1981 work began on producing a replica of the statue for outdoor display. Digital image files were used for reference while a laser beam ensured accurate measurements. Conservators used this copy to cast a faithful bronze replica of the statue, which is currently displayed in the Campidoglio.


title: Equestrian Statue of Marcus Aurelius

text: In 1908, Brown University erected a bronze replica of the statue. The statue is located on Ruth Simmons Quad, behind Sayles Memorial Hall.


title: Effective radiated power

text: Effective radiated power (ERP), synonymous with equivalent radiated power, is an IEEE standardized definition of directional radio frequency (RF) power, such as that emitted by a radio transmitter. It is the total power in watts that would have to be radiated by a half-wave dipole antenna to give the same radiation intensity (signal strength or power flux density in watts per square meter) as the actual source antenna at a distant receiver located in the direction of the antenna's strongest beam (main lobe). ERP measures the combination of the power emitted by the transmitter and the ability of the antenna to direct that power in a given direction. It is equal to the input power to the antenna multiplied by the gain of the antenna. It is used in electronics and telecommunications, particularly in broadcasting to quantify the apparent power of a broadcasting station experienced by listeners in its reception area.


title: Effective radiated power

text: An alternate parameter that measures the same thing is effective isotropic radiated power (EIRP). Effective isotropic radiated power is the hypothetical power that would have to be radiated by an isotropic antenna to give the same ("equivalent") signal strength as the actual source antenna in the direction of the antenna's strongest beam. The difference between EIRP and ERP is that ERP compares the actual antenna to a half-wave dipole antenna, while EIRP compares it to a theoretical isotropic antenna. Since a half-wave dipole antenna has a gain of 1.64 (or 2.15 dB) compared to an isotropic radiator, if ERP and EIRP are expressed in watts their relation is


title: Effective radiated power

text: Effective radiated power and effective isotropic radiated power both measure the power density a radio transmitter and antenna (or other source of electromagnetic waves) radiates in a specific direction: in the direction of maximum signal strength (the "main lobe") of its radiation pattern. This apparent power is dependent on two factors: the total power output and the radiation pattern of the antenna – how much of that power is radiated in the desired direction. The latter factor is quantified by the antenna gain, which is the ratio of the signal strength radiated by an antenna in its direction of maximum radiation to that radiated by a standard antenna. For example, a 1,000-watt transmitter feeding an antenna with a gain of 4 (6 dBi) will have the same signal strength in the direction of its main lobe, and thus the same ERP and EIRP, as a 4,000-watt transmitter feeding an antenna with a gain of 1 (0 dBi). So ERP and EIRP are measures of radiated power that can compare different combinations of transmitters and antennas on an equal basis.


title: Effective radiated power

text: In spite of the names, ERP and EIRP do not measure transmitter power, or total power radiated by the antenna, they are just a measure of signal strength along the main lobe. They give no information about power radiated in other directions, or total power. ERP and EIRP are always greater than the actual total power radiated by the antenna.


title: Effective radiated power

text: The difference between ERP and EIRP is that antenna gain has traditionally been measured in two different units, comparing the antenna to two different standard antennas; an isotropic antenna and a half-wave dipole antenna:


title: Effective radiated power

text: In contrast to an isotropic antenna, the dipole has a "donut-shaped" radiation pattern, its radiated power is maximum in directions perpendicular to the antenna, declining to zero on the antenna axis. Since the radiation of the dipole is concentrated in horizontal directions, the gain of a half-wave dipole is greater than that of an isotropic antenna. The isotropic gain of a half-wave dipole is 1.64, or in decibels 10 log 1.64 = 2.15 dBi, so


title: Effective radiated power

text: The transmitter is usually connected to the antenna through a transmission line. Since the transmission line may have significant losses formula_19, the power applied to the antenna is usually less than the output power of the transmitter formula_20. The relation of ERP and EIRP to transmitter output power is


title: Effective radiated power

text: If the signal path is in free space (line-of-sight propagation with no multipath) the signal strength (power flux density in watts per square meter) formula_23 of the radio signal on the main lobe axis at any particular distance formula_24 from the antenna can be calculated from the EIRP or ERP. Since an isotropic antenna radiates equal power flux density over a sphere centered on the antenna, and the area of a sphere with radius formula_24 is formula_26 then


title: Effective radiated power

text: However if the radio waves travel by ground wave as is typical for medium or longwave broadcasting, skywave, or indirect paths play a part in transmission, the waves will suffer additional attenuation which depends on the terrain between the antennas, so these formulas are not valid.


title: Effective radiated power

text: Because ERP is calculated as antenna gain (in a given direction) as compared with the maximum directivity of a half-wave dipole antenna, it creates a mathematically virtual effective dipole antenna oriented in the direction of the receiver. In other words, a notional receiver in a given direction from the transmitter would receive the same power if the source were replaced with an ideal dipole oriented with maximum directivity and matched polarization towards the receiver and with an antenna input power equal to the ERP. The receiver would not be able to determine a difference. Maximum directivity of an ideal half-wave dipole is a constant, i.e., 0 dBd = 2.15 dBi. Therefore, ERP is always 2.15 dB less than EIRP. The ideal dipole antenna could be further replaced by an isotropic radiator (a purely mathematical device which cannot exist in the real world), and the receiver cannot know the difference so long as the input power is increased by 2.15 dB.


title: Effective radiated power

text: Unfortunately, the distinction between dBd and dBi is often left unstated and the reader is sometimes forced to infer which was used. For example, a Yagi–Uda antenna is constructed from several dipoles arranged at precise intervals to create better energy focusing (directivity) than a simple dipole. Since it is constructed from dipoles, often its antenna gain is expressed in dBd, but listed only as dB. Obviously this ambiguity is undesirable with respect to engineering specifications. A Yagi–Uda antenna's maximum directivity is 8.77 dBd = 10.92 dBi. Its gain necessarily must be less than this by the factor η, which must be negative in units of dB. Neither ERP nor EIRP can be calculated without knowledge of the power accepted by the antenna, i.e., it is not correct to use units of dBd or dBi with ERP and EIRP. Let us assume a 100-watt (20 dBW) transmitter with losses of 6 dB prior to the antenna. ERP < 22.77dBW and EIRP < 24.92dBW, both less than ideal by η in dB. Assuming that the receiver is in the first side-lobe of the transmitting antenna, and each value is further reduced by 7.2 dB, which is the decrease in directivity from the main to side-lobe of a Yagi-Uda. Therefore, anywhere along the side-lobe direction from this transmitter, a blind receiver could not tell the difference if a Yagi-Uda was replaced with either an ideal dipole (oriented towards the receiver) or an isotropic radiator with antenna input power increased by 1.57 dB.


title: Effective radiated power

text: Polarization has not been taken into account so far, but it must be properly clarified. When considering the dipole radiator previously we assumed that it was perfectly aligned with the receiver. Now assume, however, that the receiving antenna is circularly polarized, and there will be a minimum 3 dB polarization loss "regardless" of antenna orientation. If the receiver is also a dipole, it is possible to align it orthogonally to the transmitter such that theoretically zero energy is received. However, this polarization loss is not accounted for in the calculation of ERP or EIRP. Rather, the receiving system designer must account for this loss as appropriate. For example, a cellular telephone tower has a fixed linear polarization, but the mobile handset must function well at any arbitrary orientation. Therefore, a handset design might provide dual polarization receive on the handset so that captured energy is maximized regardless of orientation, or the designer might use a circularly polarized antenna and account for the extra 3 dB of loss with amplification.


title: Effective radiated power

text: For example, an FM radio station which advertises that it has 100,000 watts of power actually has 100,000 watts ERP, and "not" an actual 100,000-watt transmitter. The transmitter power output (TPO) of such a station typically may be 10,000 to 20,000 watts, with a gain factor of 5 to 10 (5× to 10×, or 7 to 10 dB). In most antenna designs, gain is realized primarily by concentrating power toward the horizontal plane and suppressing it at upward and downward angles, through the use of phased arrays of antenna elements. The distribution of power versus elevation angle is known as the vertical pattern. When an antenna is also directional horizontally, gain and ERP will vary with azimuth (compass direction). Rather than the average power over all directions, it is the apparent power in the direction of the antenna's main lobe that is quoted as a station's ERP (this statement is just another way of stating the definition of ERP). This is particularly applicable to the huge ERPs reported for shortwave broadcasting stations, which use very narrow beam widths to get their signals across continents and oceans.


title: Effective radiated power

text: ERP for FM radio in the United States is always relative to a theoretical reference half-wave dipole antenna. (That is, when calculating ERP, the most direct approach is to work with antenna gain in dBd). To deal with antenna polarization, the Federal Communications Commission (FCC) lists ERP in both the horizontal and vertical measurements for FM and TV. Horizontal is the standard for both, but if the vertical ERP is larger it will be used instead.


title: Effective radiated power

text: The maximum ERP for US FM broadcasting is usually 100,000 watts (FM Zone II) or 50,000 watts (in the generally more densely populated Zones I and I-A), though exact restrictions vary depending on the class of license and the antenna height above average terrain (HAAT). Some stations have been grandfathered in or, very infrequently, been given a waiver, and can exceed normal restrictions.


title: Effective radiated power

text: For most microwave systems, a completely non-directional isotropic antenna (one which radiates equally and perfectly well in every direction – a physical impossibility) is used as a reference antenna, and then one speaks of EIRP (effective "isotropic" radiated power) rather than ERP. This includes satellite transponders, radar, and other systems which use microwave dishes and reflectors rather than dipole-style antennas.


title: Effective radiated power

text: In the case of medium wave (AM) stations in the United States, power limits are set to the actual transmitter power output, and ERP is not used in normal calculations. Omnidirectional antennas used by a number of stations radiate the signal equally in all directions. Directional arrays are used to protect co- or adjacent channel stations, usually at night, but some run directionally 24 hours. While antenna efficiency and ground conductivity are taken into account when designing such an array, the FCC database shows the station's transmitter power output, not ERP.


title: Effective radiated power

text: According to the Institution of Electrical Engineers (UK), ERP is often used as a general reference term for radiated power, but strictly speaking should only used when the antenna is a half-wave dipole, and is used when referring to FM transmission.


title: Effective radiated power

text: Effective monopole radiated power (EMRP) may be used in Europe, particularly in relation to medium wave broadcasting antennas. This is the same as ERP, except that a short vertical antenna (i.e. a short monopole) is used as the reference antenna instead of a half-wave dipole.


title: Effective radiated power

text: Cymomotive force (CMF) is an alternative term used for expressing radiation intensity in volts, particularly at the lower frequencies. It is used in Australian legislation regulating AM broadcasting services, which describes it as: "for a transmitter, [it] means the product, expressed in volts, of: (a) the electric field strength at a given point in space, due to the operation of the transmitter; and (b) the distance of that point from the transmitter’s antenna".


title: Effective radiated power

text: It relates to AM broadcasting only, and expresses the field strength in "microvolts per metre at a distance of 1 kilometre from the transmitting antenna".


title: Effective radiated power

text: The height above average terrain for VHF and higher frequencies is extremely important when considering ERP, as the signal coverage (broadcast range) produced by a given ERP dramatically increases with antenna height. Because of this, it is possible for a station of only a few hundred watts ERP to cover more area than a station of a few thousand watts ERP, if its signal travels above obstructions on the ground.


title: Valérie Trierweiler

text: Valérie Trierweiler (; née Massonneau; born 16 February 1965) is a French journalist and author. She has hosted political talk shows and has contributed to "Paris Match". She is best known for having been the partner of the president of France, François Hollande, until January 2014.


title: Valérie Trierweiler

text: Valérie Massonneau was born in Angers, the fifth child of six. Her father, Jean-Noël Massonneau, had lost a leg on a landmine during the Second World War, when he was 13, and died at the age of 53, when his daughter was 21. Her mother worked at the front desk of the Angers ice rink following the death of her father.


title: Valérie Trierweiler

text: Massonneau studied history and political science and obtained a Diplôme d'études supérieures spécialisées in political science from the University of Paris 1 Pantheon-Sorbonne.


title: Valérie Trierweiler

text: In 2005, Trierweiler began to host political talk shows, especially interviews, on the "Direct 8" television channel. She fronted the weekly political talk show "Le Grand 8" until 2007 and with Mikaël Guedj has co-hosted the weekly show "Politiquement parlant" ("politically speaking") since September of that year.


title: Valérie Trierweiler

text: In 2012, Trierweiler announced that she would keep her contract as a journalist with the "Paris Match" magazine during the presidency of her boyfriend, Francois Hollande.


title: Valérie Trierweiler

text: On 12 June 2012, Trierweiler caused widespread controversy by tweeting in support of Olivier Falorni, who was standing for election as a dissident socialist candidate at La Rochelle, against Ségolène Royal, Hollande's former partner. Hollande had already made public his own support for Royal's campaign.


title: Valérie Trierweiler

text: In 2017, Trierweiler published her first novel, "Le secret d'Adèle". The book is about the life of Adele Bloch-Bauer, best known for Gustav Klimt's "Portrait of Adele Bloch-Bauer I".


title: Valérie Trierweiler

text: Trierweiler's first marriage, to childhood friend Franck Thurieau, ended in divorce with no children. Her second marriage was to Denis Trierweiler, a sub-editor at "Paris Match" magazine, and a writer and academic. This marriage produced three children and divorce proceedings took three years (2007–2010).


title: Valérie Trierweiler

text: Trierweiler met François Hollande during the parliamentary elections of 1988 while he was living with Ségolène Royal. They began their relationship in 2007, while she was still married, and made it public in October 2010 after her divorce was publicized.


title: Valérie Trierweiler

text: In January 2014, a story in the celebrity magazine "Closer" featured seven pages of alleged revelations and photos about an affair between Hollande and the French actress Julie Gayet. Trierweiler was subsequently admitted to hospital on 10 January "for rest and some tests". On 17 January, Hollande made his first private visit to see her in hospital. On 25 January, it was announced her relationship with Hollande had ended.


title: Valérie Trierweiler

text: In September 2014, a book written by Trierweiler, "Merci pour ce moment" ("Thank You for This Moment"), was published. It details her relationship with Hollande and their breakup.


title: Hannibal, Missouri

text: Hannibal is a city along the Mississippi River in Marion and Ralls counties in the U.S. state of Missouri. According to the 2020 U.S. Census, the population was 17,312, making it the largest city in Marion County. The bulk of the city is in Marion County, with a tiny sliver in the south extending into Ralls County.


title: Hannibal, Missouri

text: Developed for river traffic, today the city is tied to vehicle traffic, intersected by Interstate 72 and U.S. Routes 24, 36, and 61. It is across the river from East Hannibal, Illinois. Hannibal is approximately northwest of St. Louis (also bordering the Mississippi), east-northeast of Kansas City and miles east of Saint Joseph (both cities on the Missouri River), and approximately west of Springfield, Illinois.


title: Hannibal, Missouri

text: Hannibal is not the county seat, but it has one of two county courthouses. There is also one in Palmyra, the county seat, which is located more centrally in the county. Hannibal is the principal city of the Hannibal, Missouri micropolitan area, which consists of both Marion and Ralls counties.


title: Hannibal, Missouri

text: The site of Hannibal was originally inhabited by various cultures of indigenous Native American tribes.


title: Hannibal, Missouri

text: The river community is best known as the mid-19th-century boyhood home of author Samuel Langhorne Clemens (aka Mark Twain, 1835-1910). Twain drew from his childhood settings for his novels "The Adventures of Tom Sawyer" (1876) and "Adventures of Huckleberry Finn" (1884). Numerous historical sites are associated with Mark Twain and the places depicted in his fiction.


title: Hannibal, Missouri

text: Heritage tourism contributes to the Hannibal economy, as the city attracts both American and international tourists. The Mark Twain Boyhood Home & Museum marked its 100th anniversary in 2012; it has had visitors from all 50 states and some 60 countries. Most Hannibal residents enjoy the visitors, and the town at large benefits from tourism revenue.


title: Hannibal, Missouri

text: After the United States acquired the Louisiana Territory west of the Mississippi in 1803, European-American settlers began to enter the area. Its early European settlements were established by ethnic French colonists, some from Illinois, who largely spoke French and were Roman Catholic in religion.


title: Hannibal, Missouri

text: Hannibal was laid out in 1819 by Moses Bates and named after Hannibal Creek (now known as Bear Creek). The name is derived from Hannibal, a hero of ancient Carthage (now in Tunisia).


title: Hannibal, Missouri

text: The city grew slowly, with a population of 30 by 1830. But by 1846, Hannibal was Missouri's third-largest city when the Hannibal and St. Joseph Railroad was organized by John M. Clemens (Mark Twain's father) and associates. This railway was built to connect to St. Joseph, Missouri in the west, then the state's second-largest city. This railroad was the westernmost line before the Transcontinental Railroad was constructed. It transported mail for delivery to the first outpost of the Pony Express.


title: Hannibal, Missouri

text: Construction of railroads to the area and increased steamboats on the Mississippi River had stimulated growth. In 1843 the city had also annexed the town of South Hannibal. Hannibal gained "city" status by 1845. By 1850 it had 2,020 residents.


title: Hannibal, Missouri

text: In the late 19th and early 20th centuries, the city has served as a regional marketing center for livestock and grain, as well as other products produced locally, such as cement and shoes. Cement for the Empire State Building (completed 1931) and Panama Canal was manufactured at the Atlas Portland Cement Company in the nearby unincorporated company town of Ilasco.


title: Hannibal, Missouri

text: The Mark Twain Memorial Lighthouse was constructed in 1933 as a public works project under President Franklin D. Roosevelt. It has been lit on ceremonial occasions at three separate times by Presidents Roosevelt, John F. Kennedy, and Bill Clinton. Rockcliffe Mansion, a private house on a knoll in Hannibal, is listed on the National Register of Historic Places.


title: Hannibal, Missouri

text: In 2011, the Mark Twain Boyhood Home and Museum released "", a CD featuring entertainers who recount Mark Twain's life in spoken word and song. Several songs were written especially for the project and refer to Hannibal, including "Huck Finn Blues" by Brad Paisley and "Run Mississippi" by Rhonda Vincent. Other artists include Jimmy Buffett as Huckleberry Finn, Clint Eastwood as Twain, and Garrison Keillor as the narrator of the project.


title: Hannibal, Missouri

text: Hannibal is next to the Mississippi River and is situated across the river from East Hannibal, Illinois. According to the United States Census Bureau, the city has a total area of , of which is land and is water.


title: Hannibal, Missouri

text: Hannibal's climate is hot-summer humid continental ("Dfa"), with cold, snowy winters and hot, humid summers. Three months average below freezing, seven months average above 50°F, and three months average above 22°C.


title: Hannibal, Missouri

text: At the 2010 census, there were 17,916 people, 7,117 households, and 4,400 families living in the city. The population density was . There were 8,021 housing units at an average density of . The racial makeup of the city was 88.8% White, 7.1% African American, 0.2% Native American, 0.6% Asian, 0.1% Pacific Islander, 0.5% from other races, and 2.7% from two or more races. Hispanic or Latino of any race were 1.8%.


title: Hannibal, Missouri

text: Of the 7,117 households, 31.3% had children under the age of 18 living with them, 43.2% were married couples living together, 14.5% had a female householder with no husband present, 4.2% had a male householder with no wife present, and 38.2% were non-families. 31.6% of households were one person and 13% were one person aged 65 or older. The average household size was 2.36 and the average family size was 2.96.


title: Hannibal, Missouri

text: The age distribution was 23.5% of residents were under the age of 18, 11.2% between the ages of 18 and 24, 24.4% from 25 to 44, 26% from 45 to 64, and 14.9% 65 or older. The median age was 37.3 years. The gender makeup of the city was 47.5% male and 52.5% female.


title: Hannibal, Missouri

text: As of the census of 2000, there were 17,757 people, 7,017 households, and 4,554 families living in the city. The population density was 1,215.3 people per square mile (469.3/km). There were 7,886 housing units at an average density of 539.7/sq mi (208.4/km). The racial makeup of the city was 90.61% White, 6.57% African American, 0.35% Native American, 0.35% Asian, 0.07% Pacific Islander, 0.25% from other races, and 1.79% from two or more races. Hispanic or Latino of any race were 1.13% of the population. 25.9% were of American, 23.8% German, 10.9% Irish, and 10.0% English ancestry according to self-identification in Census 2000.


title: Hannibal, Missouri

text: Of the 7,017 households 32.5% had children under the age of 18 living with them, 48.0% were married couples living together, 13.6% had a female householder with no husband present, and 35.1% were non-families. 30.6% of households were one person and 15.0% had someone living alone who was 65 years of age or older. The average household size was 2.40 and the average family size was 2.98.


title: Hannibal, Missouri

text: The age distribution was 25.8% under the age of 18, 10.5% from 18 to 24, 26.3% from 25 to 44, 20.6% from 45 to 64, and 16.8% who were 65 years of age or older. The median age was 36 years. For every 100 females, there were 86.7 males. For every 100 females age 18 and over, there were 81.8 males.


title: Hannibal, Missouri

text: The median household income was $29,892 and the median family income was $37,264. Males had a median income of $30,677 versus $20,828 for females. The per capita income for the city was $16,902. About 11.3% of families and 14.1% of the population were below the poverty line, including 18.2% of those under age 18 and 10.8% of those age 65 or over.


title: Hannibal, Missouri

text: A thriving artist community has developed here because of its central location between the East and West coasts, and affordable and stable real estate prices.


title: Hannibal, Missouri

text: The Underwood Company built the General Mills plant here because its founder appreciated Mark Twain's writing and wanted to help his hometown.


title: Hannibal, Missouri

text: Major employers include the Hannibal Regional Hospital and Hannibal Clinic. Major manufacturers include BASF Chemical Corporation (formally American Cyanamid), General Mills, and Watlow Electric Manufacturing Company. The Swiss Colony maintains a data call center in Hannibal.


title: Hannibal, Missouri

text: Because Hannibal is a Certified Local Government, residents, and business owners have access to federal and state tax credits, grants, and other funding sources.


title: Hannibal, Missouri

text: Tourism is a major part of Hannibal's economy, in large part because Samuel Clemens lived there as a boy and immortalized the town under his pen name, Mark Twain. The Mark Twain Boyhood Home & Museum and Mark Twain Cave are two of the city's major attractions.


title: Hannibal, Missouri

text: Hannibal has a Home Rule Charter form of government. Public services include police, fire, parks and recreation, public works, streets, inspections, tourism, library, and airport. There is a municipal court, and the Marion County Courthouse is located in Hannibal. A second county courthouse is located in the county seat in Palmyra.


title: Hannibal, Missouri

text: Hannibal High School was founded in 1896. This public high school is part of the Hannibal School District #60, with K-12 grades serving Hannibal and surrounding areas. It is located at 4500 McMasters Ave. 63401.


title: Hannibal, Missouri

text: Hannibal-LaGrange University is a four-year, Christian liberal arts university accredited by the Higher Learning Commission; it is a member of the North Central Association of Colleges and Schools. Founded in 1858 in LaGrange, Missouri, the campus moved downriver to Hannibal in 1928. Dr. Anthony Allen was elected the 17th president of Hannibal-LaGrange University in 2012.


title: Hannibal, Missouri

text: Moberly Area Community College (MACC-Hannibal Area Higher Education Center) is a two-year community college established in 1999. The MACC-Hannibal Campus is located on Shinn Lane near the hospital.


title: Hannibal, Missouri

text: The city is served by the "Hannibal Courier-Post" newspaper, printed daily on Tuesday through Saturday. KHQA is a television station licensed to Hannibal and located in Quincy, Illinois. Radio stations licensed to Hannibal include KGRC 92.9 FM, KHBL 96.9 FM, KHMO 1070 AM, and KJIR 91.7 FM.


title: Hannibal, Missouri

text: Interstate 72 was extended into Hannibal in 2000 from Illinois across the Mark Twain Memorial Bridge. Interstate 72 extends west to the intersection with U.S. Route 61. Future plans call for extending Interstate 72 west along U.S. Route 36 to Cameron, Missouri. This will give Hannibal an east-west link connecting Kansas City to Springfield. The Chicago–Kansas City Expressway links Hannibal from Kansas City to Chicago, Illinois. U.S. Route 61 goes from St. Louis in the south to St. Paul, Minnesota; it is known as the Avenue of the Saints corridor.


title: Hannibal, Missouri

text: Hannibal Regional Airport (formerly Hannibal Municipal Airport) was renamed in 2003 as William P. Lear Field, in honor of Lear. He grew up in Hannibal and invented the Lear Jet. The airport is located west of the southern area and has one runway x .


title: Hannibal, Missouri

text: Freight railroad tracks link Hannibal in all directions: Burlington Northern Santa Fe (BNSF) tracks lead north to West Quincy and Burlington, IA and south to St. Louis. Norfolk Southern (NS) tracks lead west to Kansas City and east to Springfield and Decatur.


title: Bristol Cars

text: Bristol Cars were manufacturers of hand-built luxury cars headquartered in Bristol, England. After being placed in receivership and being taken over in 2011, it entered liquidation in February 2020.


title: Bristol Cars

text: After the Second World War, the car division of the Bristol Aeroplane Company was formed, later becoming Bristol Cars Limited.


title: Bristol Cars

text: Bristol had only one sales showroom, on the corner of Kensington High Street and Holland Road in London.


title: Bristol Cars

text: It was always a low-volume manufacturer; the most recent published official production figures were for 1982, which stated that 104 cars were produced in that year.


title: Bristol Cars

text: The company suspended manufacturing in March 2011, when administrators were appointed, 22 staff were made redundant at the factory in Filton, Bristol and subsequently the company was dissolved. In April 2011, a new company was formed by the administrator to sell the original assets to Kamkorp. Since 2011, the company has been restoring and selling all models of the marque while a new model was being developed. The company had revealed a desire to return to automotive production in 2018 with an all-new model, called the "Bullet", initially dubbed "Project Pinnacle". The car was first revealed to the public on 26 July 2016, and homologation was set to have begun some time in 2018.


title: Bristol Cars

text: The British aircraft industry suffered a dramatic loss of orders and great financial difficulties following the Armistice of 1918. To provide immediate employment for its considerable workforce, the Bristol Aeroplane Company undertook the manufacture of a light car (the single-seat Bristol Monocar, powered by a motorcycle engine), the construction of car bodies for Armstrong Siddeley and bus bodies for their sister company, Bristol Tramways.


title: Bristol Cars

text: On the outbreak of World War II, Sir George Stanley White, managing director of the Bristol Aeroplane Company from 1911 to 1954, was determined not to suffer the same difficulties a second time. The company now employed 70,000 and he knew he must plan for the time when the wartime demand for Bristol aircraft and aircraft engines would suddenly end. The company began working with AFN Ltd, makers of Frazer Nash cars and British importer of BMWs before the war, on plans for a joint venture in automotive manufacture.


title: Bristol Cars

text: As early as 1941, a number of papers were written or commissioned by George S. M. White, Sir Stanley's son, proposing a post-war car manufacturing division. It was decided to purchase an existing manufacturer for this purpose. Alvis, Aston Martin, Lagonda, ERA and Lea-Francis were considered.


title: Bristol Cars

text: A chance discussion took place in May 1945, between D. A. Aldington, a director of Frazer Nash then serving as an inspector for the wartime Ministry of Aircraft Production (MAP), and Eric Storey, an assistant of George White at the Bristol Aeroplane Company. It led to the immediate take-over of Frazer Nash by the aeroplane company.


title: Bristol Cars

text: Aldington and his two brothers had marketed the Frazer Nash BMW before the war, and proposed to build an updated version after demobilisation. This seemed the perfect match for the aeroplane company's own ambitions to manufacture a high quality sports car. With the support of the War Reparations Board, H. J. Aldington travelled to Munich and purchased the rights to manufacture three BMW models and the 328 engine.


title: Bristol Cars

text: By July 1945, BAC had created a car division and bought a controlling stake in AFN. A factory was established at Filton Aerodrome, near Bristol.


title: Bristol Cars

text: George White and Reginald Verdon-Smith of the aeroplane company joined the new Frazer Nash Board, but in January 1947, soon after the first cars had been produced, differences between the Aldingtons and Bristol led to the resale of Frazer Nash. The Bristol car division became an independent entity.


title: Bristol Cars

text: Bristol Cars was sold after its parent joined with other British aircraft companies in 1960 to create the British Aircraft Corporation (BAC), which later became part of British Aerospace.


title: Bristol Cars

text: The car division originally merged with Bristol Siddeley Engines, and was marked for closure, but was bought in September 1960 by George S.M. White the chairman and effective founder. White retained the direction of the company, but sold a forty per cent shareholding to Tony Crook, a leading Bristol agent. Crook became sole distributor.


title: Bristol Cars

text: In September 1969, only a month before the unveiling of the new Bristol 411 at the Earl's Court Motor Show, Sir George White (as he had become) suffered a serious accident in his Bristol 410. The car was only superficially damaged, but he suffered severe trauma.


title: Bristol Cars

text: As time passed it became clear that he would never regain his health sufficiently to return to full-time work. To safeguard the future of his workforce, he decided in 1973 to sell his majority shareholding to Crook. As the ties with the White family were severed, British Aerospace requested the company to move its factory from Filton Aerodrome and it found new premises in nearby Patchway. The showroom on Kensington High Street became the head office, with Crook shuttling between the two in Bristol's light aircraft.


title: Bristol Cars

text: Under Crook's direction the company produced at least six types, the names of which were largely borrowed from Bristol's aeronautical past: the Beaufighter, Blenheim, Britannia and Brigand.


title: Bristol Cars

text: In February 1997, Crook, then aged 77, sold a fifty per cent holding in Bristol Cars to Toby Silverton, with an option to take full control within four years. Silverton, then son-in-law of Joe Lewis of the Tavistock Group and son of Arthur Silverton of Overfinch, joined the board with his father.


title: Bristol Cars

text: Crook and Toby Silverton produced the Speedster, Bullet, Blenheim and 411 Series 6, though 2002 saw the transfer of Bristol Cars fully into the ownership of Silverton and the Tavistock Group, with Silverton in the chair and Crook remaining as managing director. Together they developed a V10 engined two-seater named after the first Sir George White's First World War two-seater aircraft, the Bristol Fighter.


title: Bristol Cars

text: Crook finally relinquished his connection with Bristol Cars in August 2007. In March 2011, it was announced that Bristol Cars Limited had been placed into administration; it was that company that was renamed and subsequently dissolved by the administrator.


title: Bristol Cars

text: HJ Aldington, a director of the Bristol Aeroplane Company affiliated AFN (BMW's pre-war concessionaire in the UK), used his British Army connections to visit the bombed BMW factory in Munich several times post-war. In 1945 he took plans for BMW cars back to Britain, and BMW chief engineer, Dr. Fritz Fiedler was also employed. Its first car was the Bristol 400, prototyped in 1946 and introduced at the 1947 Geneva Motor Show. Derived from immediately pre-WW2 BMW products (thanks to a connection to BMW through Frazer Nash), the chassis was based on the BMW 326, the engine on the 328, and the body on the 327. Even a variation on the famous double-kidney BMW grille was retained. Bristol, however, did a thorough examination of the car's handling and ended up with performance "only matched by outright purpose-built competition cars". Seven hundred of the Bristol 400 were built, 17 of which received "handsome" drophead bodywork from Pininfarina.


title: Bristol Cars

text: In 1949, the 400 was joined by the five-place 401. Bodied by Touring, it was aerodynamically sleeker, accelerated better, and had higher top speed. It was joined by the drophead 402, of which just 24 examples were built.


title: Bristol Cars

text: The 403 followed in 1953, which featured improved brakes, gearbox, dampers, heater, and engine (a detuned racing motor, in fact). Bristol would use this same engine in the 450, entered at Le Mans in 1953; it broke its experimental crankshaft, but despite being less than aerodynamically ideal proved fully five seconds a lap quicker than the competition. Bristol withdrew from racing two years later.


title: Bristol Cars

text: Along with the 403 was the 404, on a shorter wheelbase, with a more powerful engine and styling reminiscent of the 450. The 404 introduced a concealed front wing-mounted spare wheel and battery. It was built to extremely exacting standards, and the price reflected it; this, plus newly introduced "punitive taxation", meant only 40 were produced.


title: Bristol Cars

text: The 405, which entered production in 1954, was much more successful, not least for being Bristol's only four-door. It remained in production until 1958, with 297 saloons and 43 drophead coupés produced in all.


title: Bristol Cars

text: It was followed in 1963 by the 408, with drastic restyling as well as improved suspension. This was succeeded by the 409. Many buyers preferred the crisp steering and gearbox of the earlier six-cylinder cars.


title: Bristol Cars

text: The 410, introduced in 1966, was a return to the high-performance touring tradition, offering the same top speed as the 409, and superior acceleration, with the same powerplant. It also saw Bristol become a private company and marked a return to quality to the exclusion of output: no more than three cars a week were to be made.


title: Bristol Cars

text: In 1969, the Bristol 411 appeared, with a new 6.2-litre Chrysler V8 (still rebuilt and modified by Bristol, as before) delivering higher top speed and even better acceleration.


title: Bristol Cars

text: Until 1961 all Bristol cars used Bristol-built derivatives of the BMW M328 2-litre six-cylinder engine. These engines also powered a number of sports and racing cars, including all post-war Frazer Nashes (apart from a few prototypes), some ACs, some Lotus and Cooper racing cars, and several others.


title: Bristol Cars

text: In 1961, with the launch of the Bristol 407, the company switched to larger Chrysler V8 engines, which were more powerful than Bristol's own, BMW derived 2.25-litre 6 cylinder engine. The Chrysler V8s could be bought off the shelf from Canadian Chrysler without the startup costs of Bristol's own 3.65-litre all alloy 6 then in development. All post-1961 Bristols, including the later Blenheim and Fighter models, used Chrysler engines.


title: Bristol Cars

text: On 3 March 2011 it was announced that Bristol Cars had gone into administration, with the loss of 22 jobs when the factory at Filton, Bristol was shut down.