Robert H. Liebeck, a world-renowned authority in the fields of aerodynamics, hydrodynamics, and aircraft design, died on 12 January 2026. He was 87 years old.
Liebeck studied aerospace engineering at the University of Illinois at Urbana-Champaign, where he earned his B.S. in 1961, his M.S. in 1962, and a Ph.D. in 1968. His Ph.D. thesis focused on the maximum lift an airfoil could generate. Using the Stratford empirical formula for the maximum pressure gradient a turbulent boundary layer could sustain without separating combined with other aerodynamic reasoning, Liebeck developed a design method that produces an airfoil shape with the maximum lift for specified conditions. Liebeck airfoils represent the limit of achievable performance. The results found application in high-altitude long-duration aircraft, cooling fans, and racecar wings.
After finishing his Ph.D., Liebeck returned to Douglas Aircraft, where he had worked during summers while at university, and made many contributions to aerodynamic design and analysis of commercial jet transport and high-altitude reconnaissance aircraft. He remained with the company as it became McDonnell Douglas and then Boeing.
In the 1990s, NASA asked whether a there was a more efficient jet transport configuration than the familiar swept wing and tube fuselage, Liebeck’s creative insights led to the Blended Wing Body (BWB) configuration. Unlike traditional aircraft with distinct cylindrical fuselages and separate wings, the BWB seamlessly integrates these components into a single, unified lifting surface. This revolutionary concept promises dramatic improvements in fuel efficiency and environmental performance.
In 2023 the U.S. Air Force tasked California-based startup JetZero with building and flying a full-scale BWB prototype, with a target flight date in 2027, aimed at creating a more fuel-efficient aircraft for both military and commercial use. Major U.S. air carriers, including United Airlines, Delta Air Lines, and Alaska Airlines, have partnered with JetZero on this development. Liebeck served as a technical advisor for the project.
In addition, he also designed aerodynamic wings for Indianapolis 500 and Formula One racing cars, as well as the keel for the 1991 America’s Cup winning yacht and the wing for a World Aerobatics Championship airplane. In an interesting example reverse technology flow from racecars to aircraft, through wind tunnel testing Liebeck identified the aerodynamic principles of the blunt edge Gurney airfoil flap that was subsequently employed on the MD-11 and other aircraft.
Liebeck was a long-standing member of the National Academy of Engineering and recognized with many of the highest honors in his profession, including the 2005 Spirit of St. Louis Medal, 2010 Daniel Guggenheim Medal, and 2012 Brigadier General Charles E. Yeager International Aeronautical Achievements Award, and he was an inductee of the 2019 International Air & Space Hall of Fame.
A 2010 AIAA Honorary Fellow, Liebeck also was recognized with the 1987 AIAA Aerodynamics Award, 2005 AIAA Aircraft Design Award, and 2016 AIAA Dryden Lectureship in Research.
In addition to his technical accomplishments, Liebeck was deeply committed to education. He served as Professor of the Practice of Aeronautics at MIT and was part of the UCI engineering faculty for over 25 years, where he taught courses in aerodynamics, aircraft performance and design, and advised students at both the undergraduate and graduate levels. He served as faculty mentor for the Design/Build/Fly and Human-Powered Airplane teams.
