Former NACA test pilots Scott Crossfield, Stan Butchart, Robert Champine, and John Griffith gathered at NASA DFRC for the "Men of Mach 2" symposium.

Former NACA test pilots Scott Crossfield, Stan Butchart, Robert Champine, and John Griffith gathered at the NASA Dryden Flight Research Center for the "Men of Mach 2" symposium, an event celebrating their work in the 1950's on the D-558-II Skyrocket aircraft.