Question: In what year did the composer of Der Lindberghflug become an American citizen ? 

Context articles: Kurt Weill
Milan Panić
Zeitoper
Ilija Lupulesku
C. Mohan
The Flight Across the Ocean
Pacific Mozart Ensemble
Edward Dugger
Božidar Kantušer
Manuel Lisa

Kurt Julian Weill (March 2, 1900April 3, 1950) was a German composer, active from the 1920s in his native country, and in his later years in the United States.
 He was a leading composer for the stage who was best known for his fruitful collaborations with Bertolt Brecht.
 With Brecht, he developed productions such as his best-known work "The Threepenny Opera", which included the ballad "Mack the Knife".
 Weill held the ideal of writing music that served a socially useful purpose.
 He also wrote several works for the concert hall.
 He became a United States citizen on August 27, 1943.
Milan Panić (Serbian Cyrillic: , ] ); born 20 December 1929) is a Serbian American former Prime Minister of Yugoslavia, humanitarian, and multimillionaire businessman based in Newport Beach and Pasadena, California.
 He served as Prime Minister of the Federal Republic of Yugoslavia from 1992 to 1993.
 During and after his time as Prime Minister, he campaigned for peace and democracy in the Balkan region.
 He ran for President of Serbia in 1992, ultimately coming in second to Slobodan Milošević in an election marked by allegations of media and vote tampering by the ruling party.
 Panić became Prime Minister of Yugoslavia while an American citizen.
 The legality of retaining US citizenship while accepting this office has been questioned based on a Constitutional prohibition of a US citizen accepting office on behalf of a foreign nation.
 Panić is the first US citizen to occupy a high-level political position in a foreign country since Golda Meir.
Zeitoper (German: "opera of the time") was a short-lived genre of opera associated with Weimar Germany.
 It is not known when or by whom the term was coined, but by 1928 Kurt Weill ("Zeitoper" in "Melos") was able to complain that it was more a slogan than a description.
 Like "opera buffa" it used contemporary settings and characters, comic or at least satiric plots ('s "Maschinist Hopkins" is a sole tragic example) and aimed at musical accessibility.
 Two distinguishing characteristics are a tendency to incorporate modern technology ("Jonny spielt auf": trains, "Der Lindberghflug": airplanes, "Von Heute auf Morgen": telephones, and even elevators) and frequent allusions to popular music, especially jazz.
 This last, more than any social satire, earned the suspicion of the political right and ensured that it would not survive into the Nazi era.
Ilija Lupulesku (born October 30, 1967 in Uzdin) is a former Serbian-Yugoslav and later American table tennis player who competed in the 1988, 1992, 1996, 2000 and in the 2004 Summer Olympics.
 He became a naturalized American citizen in 2002 and competed for the United States from 2004 to 2006 including 2004 Summer Olympics.
 Ilija Lupulesku played his first game of table tennis at age nine in his small hometown of Uzdin, Yugoslavia.
 After seeing other children playing at his local school, he picked up a paddle and began what would become his life's ambition.
 Despite his love and talent for soccer, Lupulesku, under the watchful eye of first coach Jon Bosika, committed himself to training and by age 14 was the top player on the Yugoslavian Junior National Table Tennis Team.
 Over the next 12 years, he would rise through the ranks of the world's best players and become one of the largest sport celebrities in his native Yugoslavia.
C. Mohan is an Indo-American computer scientist.
 He was born on 3 August 1955 in Tamil Nadu, India.
 After growing up there and finishing his undergraduate studies in Chennai, he moved to the United States in 1977 for graduate studies.
 After having been an Indian citizen from birth, since 2007 he has been an American citizen and an Overseas Citizen of India (OCI).
 Currently, he is an IBM Fellow based at the IBM Almaden Research Center (San Jose, California).
 He is also a Distinguished Visiting Professor at China's Tsinghua University.
The Flight across the Ocean ("Der Ozeanflug") is a "Lehrstück" by the German dramatist Bertolt Brecht, inspired by "We", Charles Lindbergh's 1927 account of his transatlantic flight.
 Written for the Baden-Baden Music Festival, it was originally entitled "Lindbergh's Flight" ("Der Lindberghflug") and premiered in 1929 with music by Kurt Weill and Paul Hindemith in a broadcast by the Southwest German Radio Orchestra under the direction of Hermann Scherchen.
Pacific Edge Voices (formerly The Pacific Mozart Ensemble (PME)) is a volunteer choral organization based in Berkeley, CA.
 The group was formed to provide a chorus of professional quality for highly skilled and experienced singers who did not wish to make singing a full-time profession.
 It was to be large enough to perform the major concert literature, but small enough to remain highly selective.
 PEV presents a wide range of choral musical styles, including, but not limited to, traditional choral literature, new works by contemporary composers and a cappella jazz and pop.
 PEV performs at least three self-produced concerts sets each year, along with various collaborations, often with prominent artists including Dave Brubeck, Meredith Monk, Kent Nagano & Sufjan Stevens.
 The first and second concerts of the year (typically Nov and March) are classically oriented programs.
 Over the years these programs have tended toward 20th-century composers.
 The chorus has become known around the San Francisco Bay Area for its innovative programming.
 A particular highlight came in 2002 when the chorus performed Kurt Weill’s Der Lindberghflug alongside works by Philip Glass, Meredith Monk and David Lang.
 The concert was presented in the East Bay on the aircraft carrier Hornet and in San Francisco in the newly constructed Aviation Museum at SFO.
 The 3rd concert set each year is an all a cappella ‘pops’ concert featuring the group in various formations from 2 up to 50, performing arrangements of jazz, pop, rock, & folk tunes.
Edward Dugger (June 6, 1894 - March 5, 1939) was a military commander and prominent African American citizen in Medford, Massachusetts.
 During his career, he served in World War One, commanded Company K of the 372nd Infantry Regiment ultimately rising to the rank of lieutenant colonel.
 He was President of the West Medford Men's Community Club and Chair of the Citizen's Committee bringing Boy Scouts Troop No. 11 to the area.
 Dugger was the first African American to be appointed to the Medford City Planning Board and to have a Medford public park named after him, "Dugger Park."
 Dugger died in 1939.
Božidar Kantušer (Bozidar Kantuser) (December 5, 1921, Pavlovski Vrh, Slovenia – May 9, 1999, Paris, France) was a Slovene composer of classical music.
 He was a Slovenian citizen and an American citizen.
Manuel Lisa, also known as Manuel de Lisa (September 8, 1772 in New Orleans, Louisiana – August 12, 1820 in St. Louis, Missouri), was a Spanish citizen and later, became an American citizen who, while living on the western frontier, became a land owner, merchant, fur trader, United States Indian agent, and explorer.
 Lisa was among the founders, in St. Louis, of the Missouri Fur Company, an early fur trading company.
 Manuel Lisa gained respect through his trading among Native American tribes of the upper Missouri River region, such as the Teton Sioux, Omaha and Ponca.