He was responsible for advancing many fields in aerodynamics, dealing particularly with wind tunnels, airfoils, turbulence, boundary layers, and Schlieren photography.
Eastman Jacobs joined NACA in 1925 after earning a bachelor's degree in Electrical Engineering at the University of California, Berkeley.
[1] He quickly became one of the leading scientists at the Langley Research Center due to his work with optimizing airfoils using a variable density wind tunnel that could operate with high Reynolds numbers.
He and his colleagues were able to significantly reduce the turbulence in the wind tunnel, which led to a better understanding of boundary development around airfoil sections.
This optimization scheme produced the NACA 4-digit[2] airfoils that led to faster aircraft like the P-51 Mustang in World War II.