Qian Xuesen, or Hsue-shen Tsien (; 11 December 1911 – 31 October 2009), was a Chinese aerospace engineer and cyberneticist who made significant contributions to the field of aerodynamics and established engineering cybernetics.

Qian received his undergraduate education in mechanical engineering at National Chiao Tung University in Shanghai in 1934 and took a pre-departure transitional year in aircraft design at National Tsinghua University in Beijing. He travelled to the United States in 1935 and attained a master's degree in aeronautical engineering at the Massachusetts Institute of Technology in 1936. Afterward, he joined Theodore von Kármán's group at the California Institute of Technology in 1936, received a doctorate in aeronautics and mathematics there in 1939, and became an associate professor at Caltech in 1943. While at Caltech, Qian helped found NASA's Jet Propulsion Laboratory. He was recruited by the United States Department of Defense and the Department of War to serve in various positions, including as an expert consultant with a colonel rank in 1945. At the same time, he became an associate professor at MIT in 1946, a full professor at MIT in 1947, and a full professor at Caltech in 1949.

Qian Xuesen

During the Second Red Scare in the 1950s, the United States federal government accused him of communist sympathies. In 1950, despite protests by his colleagues, he was stripped of his security clearance. He decided to return to China but was then detained at Terminal Island in Los Angeles County, California. After spending five years under house arrest, he was released in 1955 in exchange for the repatriation of American pilots who had been captured during the Korean War. He left the United States in September 1955 on the American President Lines passenger liner SS President Cleveland, arriving in Mainland China via Hong Kong.

Qian Xuesen

Upon his return, he helped lead development of the Dongfeng ballistic missile and the Chinese space program. He also played a significant part in the construction and development of China's defense industry system, higher education and research system, rocket force, and a key technology university. For his contributions, he became known as the "Father of Chinese Rocketry", nicknamed the "King of Rocketry". He is recognized as one of the founding fathers of Two Bombs, One Satellite.

Qian Xuesen

In 1957, Qian was elected an academician of the Chinese Academy of Sciences. He served as a Vice Chairman of the National Committee of the Chinese People's Political Consultative Conference from 1987 to 1998.

He was the cousin of engineer Hsue-Chu Tsien, who was involved in the aerospace industries of both China and the United States. His nephew, Roger Y. Tsien, was the 2008 winner of the Nobel Prize in Chemistry.

Early life and education

Qian was born in Shanghai International Settlement, with ancestral roots in Lin'an, Hangzhou, in 1911. His parents were Qian Junfu and Zhang Lanjuan. He graduated from the High School Affiliated to Beijing Normal University, with Lu Shijia as classmate, and attended National Chiao Tung University (now Shanghai Jiaotong University). There, he received a bachelor's degree in mechanical engineering with an emphasis on railroad administration in 1934. He interned at Nanchang Air Force Base.

After graduating from college, Qian was admitted to Tsinghua University's Boxer Indemnity Scholarship to study in the United States. After a one-year study in aircraft design at Tsinghua University, he left Mainland China in August 1935 and went to the Massachusetts Institute of Technology (MIT) for a master's program in mechanical engineering. He received a Master of Science in aeronautical engineering from MIT on 18 December 1936.

While at MIT, he was called Hsue-Shen Tsien. He was influenced by the methods of American engineering education, especially its focus on experimentation. This was in contrast to the contemporary approach practiced by many Chinese scientists, which emphasized theoretical elements rather than "hands-on" experience. Tsien's experiments included plotting of pitot pressures using mercury-filled manometers.

Theodore von Kármán, Qian's doctoral advisor, described their first meeting:

Kármán made his home a social scene for the aerodynamicists of Pasadena, and Qian was drawn in: "Tsien enjoyed visiting my home, and my sister took to him because of his interesting ideas and straightforward manner."