58 Years Ago, the NASA’s X-15 Hit Mach 6.72 and Nearly Melted: It Is Still One of the Greatest Achievements in Military History

Pete Knight's October 1967 flight hit Mach 6.7 and came home scorched, holed, and finished — the X-15A-2 never flew again, and no pilot has flown faster in the 58 years since. The program's 199 flights, its one lost pilot, and the record-setter now standing in bare black alloy in Dayton. I got as close as the law would allow last year to it.