Igor Sikorsky

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Igor Sikorsky
Sikorsky, Igor.jpg
Studio portrait, c. 1950
Born Igor Ivanovich Sikorsky
(1889-05-25)May 25, 1889
Kiev, Russian Empire
(now Ukraine)
Died Script error: The function "death_date_and_age" does not exist.
Easton, Connecticut, US
Nationality Russian-American[1][2][3]
Alma mater Kyiv Polytechnic Institute
ETACA (now ESTACA (fr))
Occupation Aircraft designer
Known for First successful mass-produced helicopter, the Sikorsky R-4
Spouse(s) Olga Fyodorovna Simkovitch
Elisabeth Semion
Children 5
Awards Order of St. Vladimir
Howard N. Potts Medal (1933)
Daniel Guggenheim Medal (1951)
ASME Medal (1963)
Wright Brothers Memorial Trophy (1966)
National Medal of Science (1967)
John Fritz Medal (1968)

Igor Ivanovich Sikorsky (Russian: И́горь Ива́нович Сико́рский, tr. Ígor' Ivánovič Sikórskij; May 25, 1889 – October 26, 1972)[4] was a Russian–American[1][2][3] aviation pioneer in both helicopters and fixed-wing aircraft. His first success came with the S-2, the second aircraft of his design and construction. His fifth airplane, the S-5, won him national recognition as well as F.A.I. license number 64.[5] His S-6-A received the highest award at the 1912 Moscow Aviation Exhibition, and in the fall of that year the aircraft won first prize for its young designer, builder and pilot in the military competition at Saint Petersburg.[6]

After immigrating to the United States in 1919, Sikorsky founded the Sikorsky Aircraft Corporation in 1923,[7] and developed the first of Pan American Airways' ocean-crossing flying boats in the 1930s.

In 1939, Sikorsky designed and flew the Vought-Sikorsky VS-300,[8] the first viable American helicopter, which pioneered the rotor configuration used by most helicopters today.[9] Sikorsky modified the design into the Sikorsky R-4, which became the world's first mass-produced helicopter in 1942.

Early life

Igor Sikorsky was born in Kiev, Russian Empire (now Kyiv, Ukraine).[6][10][11] He was the youngest of five children. His father, Ivan Alexeevich Sikorsky, was a professor of psychology of Saint Vladimir University (now Taras Shevchenko National University), a psychiatrist with an international reputation, and an ardent Russian nationalist.[12][13][14][15]

Igor Sikorsky was an Orthodox Christian.[16] When questioned regarding his roots, he would answer: "My family is of Russian origin. My grandfather and other ancestors from the time of Peter the Great were Russian Orthodox priests."[3]

Sikorsky's mother, Mariya Stefanovna Sikorskaya (née Temryuk-Cherkasova),[17] was a physician who did not work professionally. She is sometimes called Zinaida Sikorsky. While homeschooling young Igor, she gave him a great love for art, especially in the life and work of Leonardo da Vinci, and the stories of Jules Verne. In 1900, at age 11, he accompanied his father to Germany and through conversations with his father, became interested in natural sciences. After returning home, Sikorsky began to experiment with model flying machines, and by age 12, he had made a small rubber band-powered helicopter.[18]

Sikorsky began studying at the Saint Petersburg Maritime Cadet Corps, in 1903, at the age of 14. In 1906, he determined that his future lay in engineering, so he resigned from the academy, despite his satisfactory standing, and left the Russian Empire to study in Paris. He returned to the Russian Empire in 1907, enrolling at the Mechanical College of the Kyiv Polytechnic Institute. After the academic year, Sikorsky again accompanied his father to Germany in the summer of 1908, where he learned of the accomplishments of the Wright brothers' Flyer and Ferdinand von Zeppelin's rigid airships.[19] Sikorsky later said about this event: "Within twenty-four hours, I decided to change my life's work. I would study aviation."[20]

By the start of World War I in 1914, Sikorsky's airplane research and production business in Kyiv was flourishing, and his factory made bombers during the war. After the Bolshevik revolution began in 1917, Igor Sikorsky fled his homeland, because the new government threatened to shoot him.[21] He moved to France where he was offered a contract for the design of a new, more powerful Muromets-type plane. But in November 1918 the war ended and the French government stopped subsidizing military orders, he decided to move to the United States. On March 24, 1919 he left France on the ocean liner Lorraine arriving in New York City on March 30, 1919.[21][22][23][24]

Aircraft designer

Igor Sikorsky in 1914

With financial backing from his sister Olga, Sikorsky returned to Paris, the center of the aviation world at the time, in 1909. Sikorsky met with aviation pioneers, to ask them questions about aircraft and flying. In May 1909, he returned to Russia and began designing his first helicopter, which he began testing in July 1909. Powered by a 25 horsepower Anzani engine, the helicopter used an upper and lower two-bladed lifting propeller that rotated in opposite directions at 160 rpm. The machine could only generate about 357 pounds (162 kg) of lift, not enough to lift the approximate 457 pounds (207 kg) weight. Despite his progress in solving technical problems of control, Sikorsky realized that the aircraft would never fly. He finally disassembled the aircraft in October 1909, after he determined that he could learn nothing more from the design.[25] In February 1910, he undertook to build a second helicopter, and his first airplane. By the spring, helicopter No. 2 could lift its weight of 400 pounds (180 kg), but not the additional weight of an operator.[26]

I had learned enough to recognize that with the existing state of the art, engines, materials, and – most of all – the shortage of money and lack of experience... I would not be able to produce a successful helicopter at that time.[27]

Sikorsky's first aircraft of his own design, the S-1 used a 15 hp Anzani 3-cylinder fan engine in a pusher configuration, that could not lift the aircraft. His second design called the S-2 was powered by a 25 hp Anzani engine in a tractor configuration and first flew on June 3, 1910 at a height of a few feet. On June 30 after some modifications, Sikorsky reached an altitude of "sixty or eighty feet" before the S-2 stalled and was completely destroyed when it crashed in a ravine.[28][29] Later, Sikorsky built the two-seat S-5, his first design not based on other European aircraft. Flying this original aircraft, Sikorsky earned his pilot license; Fédération Aéronautique Internationale (FAI) license No. 64 issued by the Imperial Aero Club of Russia in 1911.[30] During a demonstration of the S-5, the engine quit and Sikorsky was forced to make a crash landing to avoid a wall. It was discovered that a mosquito in the gasoline had been drawn into the carburetor, starving the engine of fuel. The close call convinced Sikorsky of the need for an aircraft that could continue flying if it lost an engine.[31] His next aircraft, the S-6 held three passengers and was selected as the winner of the Moscow aircraft exhibition held by the Russian Army in February 1912.[30]

Sikorsky Bolshoi Baltisky of 1913, before receiving its pair of pusher engines

In early 1912, Igor Sikorsky became Chief Engineer of the aircraft division for the Russian Baltic Railroad Car Works (Russko-Baltiisky Vagonny Zavod or R-BVZ)[32] in Saint Petersburg.[33] His work at R-BVZ included the construction of the first four-cylinder aircraft, the S-21 Russky Vityaz, which he initially called Le Grand when fitted with just two engines, then as the Bolshoi Baltisky (The Great Baltic) when fitted with four engines for the first time, each wing panel's pair of powerplants in a "push-pull" tandem configuration previous to the four tractor-engined Russki Vityaz.[34] He also served as the test pilot for its first flight on May 13, 1913.[34] In recognition for his accomplishment, he was awarded an honorary degree in engineering from Saint Petersburg Polytechnical Institute in 1914. Sikorsky took the experience from building the Russky Vityaz to develop the S-22 Ilya Muromets airliner. Due to outbreak of World War I, he redesigned it as the world's first four-engined bomber, for which he was decorated with the Order of St. Vladimir.

After World War I, Igor Sikorsky briefly became an engineer for the French forces in Russia, during the Russian Civil War.[35] Seeing little opportunity for himself as an aircraft designer in war-torn Europe, and particularly Russia, ravaged by the October Revolution and Civil War, he emigrated to the United States, arriving in New York on March 30, 1919.[36][37]

List of aircraft designed by Sikorsky

Russian aviators Sikorsky, Genner and Kaulbars aboard a "Russky Vityaz", c. 1913
Sikorsky S-64 Skycrane carrying a house
  • H-1 Sikorsky's first helicopter design, 1909
  • H-2 Sikorsky's second helicopter design, 1910
  • S-1 single-engine pusher biplane, Sikorsky's first fixed wing design, 1910
  • S-2 single-engine tractor biplane developed from the S-1, 1910
  • S-3 enlarged and improved version of the S-2, 1910
  • S-4 one-seat, single-engine biplane concept developed from the S-3, never flown, 1911
  • S-5 one-seat, single-engine biplane, Sikorsky's first practical aircraft, 1911
  • S-6 three-seat, single-engine biplane, 1912
  • S-7 two-seat, single-engine monoplane, 1912
  • S-8 two-seat single-engine biplane trainer, 1912
  • S-9 Krugly three-seat, single-engine monoplane, 1913
  • S-10 five-seat, single-engine biplane reconnaissance/trainer developed from the S-6, 1913
  • S-11 Polukrugly two-seat, single-engine mid-wing reconnaissance monoplane prototype, 1913
  • S-12 one-seat, single-engine trainer, Sikorsky's most successful aircraft in Russia, 1913
  • S-13 and S-14 proposed designs, never completed due to unavailability of engines
  • S-15 single-engine light bomber floatplane, 1913
  • S-16 two-seat, single-engine escort fighter, 1914–1915
  • S-17 two-seat, single-engine reconnaissance biplane based on the S-10, 1915
  • S-18 two-seat, twin-engine pusher biplane fighter/interceptor
  • S-20 two-seat biplane fighter, 1916
  • S-21 Russky Vityaz four-engine biplane airliner, first successful four engine aircraft, 1913
  • S-22–S-27 Ilya Muromets four-engine biplane airliner and heavy bomber, 1913
  • S-28 proposed four-engined biplane bomber, cancelled due to the end of WWI, 1918
  • S-29-A twin-engine biplane airliner, Sikorsky's first American design, 1924
  • S-34 twin-engine amphibian, 1926[26]:167,180
  • S-35 trimotor built for René Fonck's attempt to win the Orteig Prize, 1926[26]:169-178
  • S-36 twin engine amphibian, 1927[26]:182
  • S-37 twin-engine built for René Fonck, but then converted to a passenger plane, 1927[26]:180-182
  • S-38 twin-engine ten-seat flying boat, 1928[26]:182-183
  • S-40 four-engine amphibian built for Pan Am, 1931[26]:187-193
  • S-42 Clipper – flying boat, 1934
  • S-43 scaled-down version of S-42, 1934
  • VS-300 experimental prototype helicopter, 1939
  • VS-44 flying boat, 1942
  • R-4 world's first production helicopter, 1942

Life in the United States

Igor Sikorsky on Time magazine cover, 1953

In the U.S., Sikorsky first worked as a school teacher and a lecturer, while looking for an opportunity to work in the aviation industry. In 1932, he joined the faculty of the University of Rhode Island to form an aeronautical engineering program and remained with the university until 1948.[38] He also lectured at the University of Bridgeport.

In 1923, Sikorsky formed the Sikorsky Manufacturing Company in Roosevelt, New York.[39] He was helped by several former Russian military officers. Among Sikorsky's chief supporters was composer Sergei Rachmaninoff, who introduced himself by writing a check for US$5,000 (approximately $61,000 in 2007).[40] Although his prototype was damaged in its first test flight, Sikorsky persuaded his reluctant backers to invest another $2,500. With the additional funds, he produced the S-29, one of the first twin-engine aircraft in the US, with a capacity for 14 passengers and a speed of 115 mph.[41] The performance of the S-29, slow compared to military aircraft of 1918, proved to be a "make or break" moment for Sikorsky's funding.[citation needed]

In 1928, Sikorsky became a naturalized citizen of the United States. The Sikorsky Manufacturing Company moved to Stratford, Connecticut in 1929. It became a part of the United Aircraft and Transport Corporation (now United Technologies Corporation) in July of that year.[42] The company manufactured flying boats, such as the S-42 "Clipper", used by Pan Am for transatlantic flights.[27]

Meanwhile, Sikorsky also continued his earlier work on vertical flight while living in Nichols, Connecticut. On February 14, 1929, he filed an application to patent a "direct lift" amphibian aircraft which used compressed air to power a direct lift "propeller" and two smaller propellers for thrust.[43] On June 27, 1931, Sikorsky filed for a patent for another "direct lift aircraft", and was awarded patent No. 1,994,488 on March 19, 1935.[44] His design plans eventually culminated in the first (tethered) flight of the Vought-Sikorsky VS-300 on September 14, 1939, with the first free flight occurring eight months later on May 24, 1940. Sikorsky's success with the VS-300 led to the R-4, which became the world's first mass-produced helicopter, in 1942. Sikorsky's final VS-300 rotor configuration, comprising a single main rotor and a single antitorque tail rotor, has proven to be one of the most popular helicopter configurations, being used in most helicopters produced today.[9]

Personal life

Sergei Sikorsky at the HeliRussia 2011 Exhibition in Moscow

Sikorsky was married to Olga Fyodorovna Simkovitch in the Russian Empire. They were divorced and Olga remained in Russia with their daughter, Tania, as Sikorsky departed after the October Revolution. In 1923, Sikorsky's sisters immigrated to the US, bringing six-year-old Tania with them.[45] Sikorsky married Elisabeth Semion (1903–1995) in 1924, in New York.[46] Sikorsky and Elisabeth had four sons; Sergei, Nikolai, Igor Jr. and George.[47]

  • Tania Sikorsky von York (March 1, 1918 – September 22, 2008), Sikorsky's eldest child and only daughter. Tania was born in Kyiv. Educated in the US, she earned a B.A. at Barnard College and a doctorate at Yale University. She was one of the original faculty members of Sacred Heart University in Bridgeport, Connecticut, where she served as Professor of Sociology for 20 years.[48]
  • Sergei Sikorsky (1925– ), Sikorsky's eldest son. He joined United Technologies in 1951, and retired in 1992, as Vice-President of Special Projects at Sikorsky Aircraft.[49][50]
  • Igor Sikorsky Jr. is an attorney, businessman and aviation historian.[51] Igor Sikorsky III is also a pilot.[52]

Sikorsky died at his home in Easton, Connecticut, on October 26, 1972, and is buried in Saint John the Baptist Russian Orthodox Cemetery located on Nichols Avenue in Stratford.[53]


The Sikorsky's family house in Kyiv's historical center, October 2009

In 1966, Sikorsky was inducted into the International Air & Space Hall of Fame.[54]

Sikorsky's and Andrei Tupolev's professional careers were covered in the 1979 Soviet biopic The Poem of Wings (Russian: Поэма о крыльях) where Sikorsky was portrayed by Yury Yakovlev. A working model of Sikorsky Ilya Muromets was recreated for filming.[55]

The Sikorsky Memorial Bridge, which carries the Merritt Parkway across the Housatonic River next to the Sikorsky corporate headquarters, is named for him. Sikorsky has been designated a Connecticut Aviation Pioneer by the Connecticut State Legislature. The Sikorsky Aircraft Corporation in Stratford, Connecticut, continues to the present day as one of the world's leading helicopter manufacturers, and a nearby small airport has been named Sikorsky Memorial Airport.[56]

Sikorsky was inducted into the National Inventors Hall of Fame and the Junior Achievement U.S. Business Hall of Fame in 1987.[57][58]

In October 2011, one of the streets in Kyiv was renamed after Sikorsky. The decision was made by the City Council at the request of the U.S. Embassy in Ukraine, which opened its new office on that street.[59] The Sikorsky's family house in the city's historical center is preserved to this day but is in a neglected condition pending restoration.[citation needed]

In November 2012, one of the Russian supersonic heavy strategic bomber Tu-160, based at the Engels-2 Air Force Base, was named for Igor Sikorsky, which caused controversy among air base crew members. One of the officers said that Igor Sikorsky does not deserve it because he laid the foundations of the U.S., rather than Russian aviation. However, the Long Range Aviation command officer said that Igor Sikorsky is not responsible for the activities of his military aircraft, noted that Sikorsky had also designed the first heavy bomber for Russia.[60] In 2013, Flying magazine ranked Sikorsky number 12 on its list of the 51 Heroes of Aviation.[61]

In August 2016, the National technical university of Ukraine "Kyiv politechnical institute" was named National Technical University of Ukraine "Igor Sikorsky Kyiv Polytechnic Institute" its former student and outstanding aircraft designer.[62]

On March 22, 2018 the Kyiv City Council officially renamed Kyiv International Airport to "Igor Sikorsky Kyiv International Airport Zhuliany".[63][64]

Philosophical and religious views

Sikorsky was a deeply religious Russian Orthodox Christian[65] and authored two religious and philosophical books (The Message of the Lord's Prayer and The Invisible Encounter). Summarizing his beliefs, in the latter he wrote:

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Our concerns sink into insignificance when compared with the eternal value of human personality – a potential child of God which is destined to triumph over life, pain, and death. No one can take this sublime meaning of life away from us, and this is the one thing that matters.[66][67]

Published works

  • Sikorsky, Igor Ivan. The Message of the Lord's Prayer. New York: C. Scribner's sons, 1942. OCLC 2928920
  • Sikorsky, Igor Ivan. The Invisible Encounter. New York: C. Scribner's Sons, 1947. OCLC 1446225
  • Sikorsky, Igor Ivan. The Story of the Winged-S: Late Developments and Recent Photographs of the Helicopter, an Autobiography. New York: Dodd, Mead, 1967. OCLC 1396277

See also


  1. 1.0 1.1 "Britannica Concise Encyclopedia". Encyclopædia Britannica, Inc. 2006, p. 1751.
  2. 2.0 2.1 "Sergei Sikorsky: Reflecting on the 90th Anniversary of Sikorsky Aircraft" Quote: Some 90 years ago, on March 5, 1923, a Russian refugee named Igor Sikorsky organized a new company"
  3. 3.0 3.1 3.2 Lua error in package.lua at line 80: module 'strict' not found.
  4. Fortier, Rénald. "Igor Sikorsky: One Man, Three Careers." Archived October 16, 2013, at the Wayback Machine aviation.technomuses.ca,1996. Retrieved: October 29, 2008.
  5. Lua error in package.lua at line 80: module 'strict' not found.
  6. 6.0 6.1 Lua error in package.lua at line 80: module 'strict' not found.
  7. "About Sikorsky." Sikorsky Aircraft. Retrieved: December 11, 2008.
  8. Spenser 1998, p. 25.
  9. 9.0 9.1 Woods 1979, p. 262.
  10. "Igor Sikorsky | Historical Archives | History". sikorskyarchives.com
  11. Lua error in package.lua at line 80: module 'strict' not found.
  12. Homo Imperii A History of Physical Anthropology in Russia, Marina Mogilner 2013, p. 72.
  13. Homo Imperii A History of Physical Anthropology in Russia, Marina Mogilner 2013, p. 167.
  14. Homo Imperii A History of Physical Anthropology in Russia, Marina Mogilner 2013, p. 177.
  15. Hillis, Faith. Children of Rus': Right-Bank Ukraine and the Invention of a Russian Nation 2013, ISBN 0801452198, p. 259.
  16. Sikorskyarchives.com
  17. Mikheev, V. R. "Sikorsky: Hero, Exile, the Father of Aviation" (English translation). Pravmir.ru, October 31, 2011. Retrieved: May 16, 2012.
  18. Woods 1979, p. 254.
  19. "The Case Files: Igor Sikorsky". Franklin Institute. Retrieved: August 24, 2017.
  20. Christiano, Marilyn. "Igor Sikorsky: Aircraft and Helicopter Designer." VOA News, July 5, 2005. Retrieved: July 17, 2010.
  21. 21.0 21.1 [1] "Sergei Sikorsky: My father's fate (English translation version of an interview published in Russian by pravmir.ru)"
  22. [2] "An interview with Sergei Sikorsky in Russian by pravmir.ru"
  23. Kutuzov, Mikhail. "The Genius of Flight" (English translation). Russian Archipelago, 2012. Retrieved: May 16, 2012.
  24. Ukrainian Congress Committee of America 1978, p. 187
  25. Woods 1979, p. 255.
  26. 26.0 26.1 26.2 26.3 26.4 26.5 26.6 Lua error in package.lua at line 80: module 'strict' not found.
  27. 27.0 27.1 "Igor Sikorsky." Encyclopædia Britannica, 2009 via britannica.com. Retrieved: October 14, 2009.
  28. Lua error in package.lua at line 80: module 'strict' not found.
  29. "Sikorsky Celebrates." Popular Aviation September 1930, p. 20.
  30. 30.0 30.1 Woods 1979, p. 256.
  31. Current Biography 1940, pp. 734–736.
  32. Murphy 2005, p. 180.
  33. Lake 2002, p. 31.
  34. 34.0 34.1 Lua error in package.lua at line 80: module 'strict' not found.
  35. "Airmen leave Russia." The New York Times, June 25, 1918. Retrieved May 23, 2011.
  36. Woods 1979, p. 257.
  37. "Russian airplane will be made here." The New York Times, April 20, 1919. Retrieved: July 17, 2010.
  38. Lua error in package.lua at line 80: module 'strict' not found.
  39. Spenser 1998, p. 15.
  40. Prokhorov, Vadim. "Oldies & Oddities: Sikorsky's Piano Man" (History of Flight). Archived July 24, 2012, at archive.today Air & Space Magazine/Smithsonian, Volume 17, Issue 4, November 1, 2002. Retrieved: July 17, 2010.
  41. Current Biography 1940, p. 735.
  42. Spenser 1998, pp. 15–17.
  43. Lua error in package.lua at line 80: module 'strict' not found.
  44. "Patent number: 1994488." google.com. Retrieved: November 25, 2010.
  45. "Military Mission." Archived September 6, 2008, at the Wayback Machine The Case Files: Igor Sikorsky, Franklin Institute. Retrieved: October 29, 2008.
  46. Hacker and Vining 2007, p. 116.
  47. Skyways July 1995, p. 71.
  48. "Tania Sikorsky Von York." Foster's Daily Democrat, September 26, 2008. Retrieved: October 16, 2008.
  49. "First Helicopter Civilian Rescue November 29, 1945." Archived December 10, 2008, at the Wayback Machine Sikorskyarchives.com. Retrieved: July 17, 2010.
  50. Zenobia, Keith. "Sergei Sikorsky: Recollections of a Pioneer, The Legacy of Igor Sikorsky." PMLAA News Newsletter (Pine Mountain Lake Aviation Association), 19:6, 2004. Retrieved: December 2, 2010.
  51. Church, Diane. "Sikorsky to speak in Plainville tonight." Bristol Press, March 19, 2012.
  52. "Igor Sikorsky Seminar." Archived March 4, 2014, at the Wayback Machine Aviation Digest: Bradford Camps, June 2003.
  53. "St. John the Baptist Russian Orthodox Cemetery"
  54. Sprekelmeyer, Linda, editor. These We Honor: The International Aerospace Hall of Fame. Donning Co. Publishers, 2006. ISBN 978-1-57864-397-4.
  55. Lua error in package.lua at line 80: module 'strict' not found.
  56. "Igor I. Sikorsky: Sikorsky Aircraft." Archived January 9, 2013, at the Wayback Machine JA Worldwide. Retrieved: October 12, 2009.
  57. Ikenson 2004, p. 24.
  58. "Igor I. Sikorsky." Archived December 11, 2009, at the Wayback Machine National Inventors Hall of Fame Foundation, Inc. via invent.org. Retrieved: October 12, 2009.
  59. "Kyiv changes street name at Washington's request" Kyiv Post. Retrieved: November 26, 2011.
  60. Mikhailov, Alexei and Bal′burov, Dmitry. "Ту-160 присвоили имя американского авиаконструктора Сикорского (in Russian) (The Tu-160 was named after the American Sikorsky Aircraft Designer)." Izvestia November 13, 2012.
  61. Flyingmag.com
  62. https://kpi.ua/en/almamater
  63. [3]. Pravda.com
  64. https://www.kyiv-airport.com/kyiv-zhuliany/
  65. Faith Of the Orthodox Born in Russia
  66. "The Invisible Encounter". The Universalist Leader, Volume 130, Issue 5, 1948, p. 115.
  67. "Igor I. Sikorsky." AvStop Online Magazine. Retrieved: July 17, 2010.


  • Delear, Frank J. Igor Sikorsky: His Three Careers in Aviation. New York: Dodd Mead, 1969, Revised edition, 1976. ISBN 978-0-396-07282-9.
  • Hacker, Barton C. and Margaret Vining. American Military Technology: The Life Story of a Technology. Baltimore, Maryland: Johns Hopkins University Press, 2007. ISBN 978-0-8018-8772-7.
  • Ikenson, Ben. Patents: Ingenious Inventions, How They Work and How They Came to Be. New York: Black Dog & Leventhal Publishers, 2004. ISBN 978-1-57912-367-3.
  • Lake, Jon. The Great Book of Bombers: The World's Most Important Bombers from World War I to the Present Day. St. Paul, Minnesota: MBI Publishing Company, 2002. ISBN 0-7603-1347-4.
  • Leishman, J. Gordon. "The Dream of True Flight." Online summary: Principles of Helicopter Aerodynamics. Cambridge, UK: Cambridge University Press, 2006. ISBN 0-521-85860-7.
  • Murphy, Justin D. Military Aircraft, Origins to 1918: An Illustrated History of Their Impact (Weapons and warfare series). Santa Barbara, California, USA: ABC-CLIO, 2005. ISBN 1-85109-488-1.
  • Sikorsky, Igor Ivan. The Story of the Winged-S: Late Developments and Recent Photographs of the Helicopter, an Autobiography. New York: Dodd, Mead, originally published 1938 (updated editions, various years up to 1948), Revised edition, 1967.
  • Spenser, Jay P. Whirlybirds, A History of the U.S. Helicopter Pioneers. Seattle, Washington, USA: University of Washington Press, 1998. ISBN 0-295-97699-3.
  • Woods, Carlos C. "Memorial Tributes", pp. 253–266. Igor Ivan Sikorsky. Washington, D.C.: National Academy of Engineering (The Academy), 1979.
  • Lua error in package.lua at line 80: module 'strict' not found.
  • U.S. Patent 2,318,259
  • U.S. Patent 2,318,260

External links