Agnes Scott College

Irmgard Flugge-Lotz


July 16, 1903 - May 22, 1974

Written by Julie Cooper, Class of 1998, and Maria Banderas, Class of 2000 (Agnes Scott College)

"I wanted a life which would never be boring - a life in which new things would always occur." [2, p33] And thus began Irmgard Flugge-Lotz's career as an engineer. Flugge-Lotz was internationally renowned for her contributions to aerodynamics and automatic theory control. During the 1960's she was one of Stanford University's most distinguished professors. Several of her honors include the Achievement Award by the Society of Women Engineers in 1970, an honorary Doctor of Science degree by the University of Maryland in 1973, and selection by the American Institute of Aeronautics and Astronautics (AIAA) to give the prestigious annual von Karman Lecture in 1971. A succinct and independent evaluation of her career is provided by the citation from her honorary doctorate:

Professor Flugge-Lotz has acted in a central role in the development of the aircraft industry in the Western world. Her contributions have spanned a lifetime during which she demonstrated, in a field dominated by men, the value and quality of a woman's intuitive approach in searching for and discovering solutions to complex engineering problems. Her work manifests unusual personal dedication and native intelligence. (qtd. in Grinstein and Campbell, 37)

Born in Hameln, Germany on July 16, 1903, Lotz was raised by Oskar and Dora (Grupe) Lotz. While her father was a traveling journalist, her mother contributed to the construction business established by the Grupe family. By visiting building cites, Lotz developed a fascination with the art of construction.

In 1914, Lotz's father accepted a position writing for one of Hanover's city newspapers. At that time, Lotz was enrolled in a high school for girls, there being no coed education. The day Mr. Lotz was to report to his new job, however, World War I began, during which he was assigned to occupied Belgium for several years. With the loss of the breadwinner, Irmgard Lotz felt obligated to contribute to the family budget. In this time of need, Irmgard temporarily tutored in mathematics and Latin, providing most of the family's income. With the return of her father in poor health, Lotz continued to financially support the family.

Lotz graduated from high school in 1923 and enrolled in the male-dominated Technical University in Hanover where she studied applied mathematics. There she encountered a phenomenon which she would see during the rest of her career; she was the only woman in many of her classes. In 1927 she earned the degree of Diplom-Ingenieur, and in 1929 she became a Doktor-Ingenieur, with a thesis on the mathematical theory of heat conduction in circular cylinders. During this time she held a full-time job as a teaching assistant for practical mathematics and descriptive geometry.

Though it was difficult for a female to find a job in engineering, Lotz received two offers, one from the steel industry and one from the Aerodynamische Versuchsanstalt (AVA) in Gottingen, a research institute. She chose the latter, but she was asked to devote half of her time to clerical work, leaving the other half for research.

Lotz worked closely with the leading German aerodynamicists of the time, Ludwig Prandlt and Albert Betz, director of the institute. Before Lotz's arrival, Prandlt had been fumbling with the integro-differential equation for his lifting line theory for the spanwise lift distribution of an airplane wing. Applying her mathematical skills, Lotz was able to overcome his difficulties, solve the equation, and develop a relatively convenient method for practical use. Deservingly, Lotz was promoted to head of this dominant group dealing with aerodynamics.

In 1938, Lotz married Dr. Wilhelm Flugge. A civil engineer, Flugge had just accepted a position as a department head at the Deutche Versuchsanstalt fur Luftfahrt (DVL) in Berlin. The leaders of the DVL quickly became aware of the talent possessed by his wife and offered her a position as consultant in aerodynamics and flight dynamics. There, she began her career in automatic control theory, developing the theory of discontinuous, or on-off control systems.

In 1944, the Flugges moved their DLV activities to Saulgau. When Germany surrendered a year later, the Flugges found themselves in the French zone of occupation. In 1947, they both accepted offers to join the newly established ONERA (French National Office for Aeronautical Research) in Paris. Flugge-Lotz served as chief of a research group in aerodynamics until 1948 and published papers in both automatic control theory and aerodynamics, in which she discussed the problems arising from the increased speed of aircrafts.

After enjoying the French society as well as becoming fluent in French, the Flugges left Paris for the United States in 1948 to accept invitations from Stanford University. Since her husband was hired as a full-time professor, Flugge-Lotz could only be hired as a lecturer in engineering mechanics and research supervisor due to the nepotism policies of the University. Lack of title did not deter her from embarking upon useful research, however; she immediately undertook the guidance of Ph. D. dissertation research in aerodynamic theory. In the Spring of 1949, Flugge-Lotz taught her first Stanford course and later introduced a year- long sequence of courses in mathematical hydro- and aerodynamics for first-year graduate students.

Flugge-Lotz continued to show strong interest in fluid-mechanics, numerical methods and automatic controls. At Stanford, she developed new courses, guided the research of a succession of Ph.D. candidates, and co-authored research reports with her students. The number of her students had grown so much that by 1951 she established a weekly fluid mechanics seminar at which faculty and students met to discuss ideas. It became evident that Flugge-Lotz was carrying-on the duties of a full-time professor without official recognition. This injustice was alleviated in 1960 when Flugge-Lotz was the only female delegate from the United States at the first Congress of the International Federation of Automatic Control in Moscow. Before school opened for the Fall quarter, she was appointed full professor in both engineering mechanics, and aeronautics and astronautics. She was Stanford's first female professor in engineering. In 1970 she was awarded the Achievement award by the Society of Women Engineers. She was the first woman elected to be a Fellow of the American Institute of Aeronautics and Astronautics in 1970, and in 1971 she was the first woman to be selected to give the prestigious von Karman Lecture.

Though she retired in 1968, Flugge-Lotz continued her research on satellite control, heat transfer, and drag of high-speed vehicles. After a fulfilling career of teaching, research and the publication of over fifty technical papers, Flugge-Lotz died in Stanford Hospital in 1974; she was 70 years old. She had indeed lived a "life which would never be boring." Appropriately, her exciting contributions to the fields of engineering and mathematics will never go overlooked.

May 1997


  1. L. S. Grinstein and P. J. Campbell (eds.), Women of Mathematics (Westport, Conn., 1987), 33-40.
  2. Obituary of Irmgard Flugge-Lotz, New York Times (23 May 1974).
  3. Bailey, Martha J. American Women in Science. California: ABC-CLIO, Inc. 1994
  4. McMurray, Emily J., Editor. Notable Twentieth Century Scientists, Volume 2. "Irmgard Flugge-Lotz." Detroit: Gale Research Inc. 1995.
  5. Spreiter, John R., Milton D. Van Dyke, and Walter G. Vincenti. "In Memoriam: Irmgard Flugge-Lotz, 1903-1974," IEEE Transactions on Automatic Control, Vol. AC-20, No. 2, April 1975, 183a-183b.
  6. MathSciNet [subscription required]
  7. Author Profile at zbMath
  8. Biography at the MacTutor History of Mathematics Archive