NACA was a U.S. federal agency founded on March 3, 1915, to undertake, promote, and institutionalize aeronautical research. On October 1, 1958, the agency was dissolved, and its assets and personnel transferred to the newly created National Aeronautics and Space Administration (NASA). Among other advancements, NACA research and development produced the NACA duct, a type of air intake used in modern automotive applications, the NACA cowling, and several series of NACA airfoils which are still used in aircraft manufacturing. During World War II, NACA was described as "The Force Behind Our Air Supremacy" due to its key role in producing working superchargers for high altitude bombers, and for producing the cutting edge wing profiles for the North American P-51 Mustang. NACA was also key in developing the area rule that is used on all modern supersonic aircraft, and was responsible for the key compressibility research that allowed the Bell X-1 to break the sound barrier.