Born: 1903 (Hamelin, Germany)
Died: 1974
Biography:
Irmgard Flügge-Lotz, née Lotz (16 July 1903 – 22 May 1974), was a German-American mathematician and aerospace engineer. She was a pioneer in the development of the theory of discontinuous automatic control, which has found wide application in hysteresis control systems such as guidance systems, electronics, fire-control systems, and temperature regulation.
Flügge-Lotz was born in Hamelin, Germany on 16 July 1903. Encouraged by her mother, whose family had a long history in construction, she developed an early interest in technical subjects. Her uncle, an architect, often took her to construction sites, and she regularly attended technical films at discounted matinee shows.
During World War I, Flügge-Lotz’s father, Osark, was drafted for military service, leaving her as the main breadwinner for the family. She became a math tutor while studying at a girls’ Gymnasium in Hanover. When her father returned to Hanover in poor health, she continued working to support the family.
Flügge-Lotz graduated from the Gymnasium in 1923 and enrolled at Leibniz University Hannover, where she pursued studies in mathematics and engineering. She was often the only woman in her classes, specializing in applied mathematics and fluid dynamics. In 1927, she earned her Diplom-Ingenieur degree and remained at the university for her doctorate.
In 1929, Flügge-Lotz completed her doctorate in engineering, focusing on the mathematical theory of circular cylinders and heat conduction. Her research led her to join the Aerodynamische Versuchsanstalt (AVA) in Göttingen, one of the most esteemed aeronautical research institutions in Europe. At AVA, she worked closely with renowned aerodynamicists Ludwig Prandtl and Albert Betz.
At the AVA, Flügge-Lotz was faced with a daunting challenge. Prandtl had been struggling to solve a differential equation for his lifting-line theory, which explained the spanwise lift distribution of an airplane wing. With her exceptional mathematical skills, Flügge-Lotz successfully solved this equation and developed a practical method known as the Lotz method in 1931. Her technique for calculating the lift on a three-dimensional wing quickly gained international recognition and became a widely used standard in the field.
In recognition of her contributions, Flügge-Lotz was promoted to team leader at AVA. However, in 1933, the rise of the Nazi regime in Germany forced her to leave her position due to her Jewish heritage. She and her husband, Wolfgang Flügge, a physicist, emigrated to the United States.
In the United States, Flügge-Lotz found opportunities to continue her pioneering work. In 1944, she published her influential book, Discontinuous Automatic Control, which laid the foundation for the theory of discontinuous control systems. Her research revolutionized the field and opened up new possibilities for the development of guidance systems, fire-control systems, and temperature regulation.
Flügge-Lotz joined the faculty at Stanford University in 1959 and became the first female engineering professor at the university in 1961. She continued her groundbreaking research and mentored numerous students throughout her career. In 1970, she retired from Stanford as an emeritus professor.
Flügge-Lotz’s contributions to engineering and mathematics earned her numerous accolades. In 1967, she became the first female engineer elected as a Fellow of the American Institute of Aeronautics and Astronautics. Her groundbreaking work paved the way for future generations of female engineers, and she remains an inspiration to this day.
Awards:
– Fellow of the American Institute of Aeronautics and Astronautics (1967)