When Arthur Cutts Willard was appointed president in 1934, he dispensed with the traditional inauguration ceremonies because of the Depression but also because of his dislike for public ostentation. He served for many years as a professor and as head of the mechanical engineering department. Willard received international recognition for his ventilation research that helped make possible the Holland Vehicular Tunnel between Manhattan and Jersey City. His expertise in heating and ventilation was called upon by the Army's Chemical Warfare Service in 1926 and Public Health Service in 1927.
The University budget was at its lowest point since 1921, and there was little hope for state funds. After four months of negotiations, Willard was successful in obtaining federal funds to complete plans for the College of Medicine and College of Dentistry laboratories in Chicago. The newly formed University of Illinois Foundation was named as trustee for the bond issue. In Chicago, enrollment in the College of Pharmacy became the highest in the United States; the College of Medicine, second; and the College of Dentistry, seventh. Federal funds were also used to build the Illini Union and the Natural Resources building, both in Urbana, and to make extensive additions to the Library, McKinley Hospital and the Illinois Union building on the Chicago campus.
In 1946, the University of Illinois established the nationally recognized Institute of Aviation at Willard Airport, named for the university president. The first scheduled airline service began in 1954. The terminal building was built in 1960 and used until a new terminal opened in 1987. In 1969, Willard Airport was the second-busiest airport in Illinois.