Dr. Karl Nickel (1924-2009), best known for his work with interval mathematics computations, began his academic career with work on the solution of aerodynamic problems and boundary layer theory. During the 1940s, Nickel worked for Reimer and Walter Horten, the designers and builders of swept-wing aircraft, as a mathematician. Nickel also sampled the prone layout of the Horten III-f, which he flew in 1944. After World War II, Nickel received his Diploma in Mathematics from Gottingen University in 1948 and his Doctor of Mathematics from the Universities of Tubingen and Stuttgart in 1949. From 1951-1955 Nickel was employed in aircraft design in Argentina. In the mid-1950s, Nickel returned to Germany where he served as a professor of applied mathematics at the University of Karlsruhe and the University of Freiburg.