This was the agency responsible for aeronautical research in the United States from 1915 to 1958. It was later replaced by NASA (National Aeronautics and Space Administration) which expanded the focus to include space exploration.
Even though NACA is no longer active, its legacy lives on in the form of:
* NACA airfoils: a series of airfoil shapes developed by NACA which are still widely used in aircraft design today.
* NACA reports: the technical reports published by NACA which remain valuable sources of information for researchers and engineers.