What is the fastest plane to ever exist, including aircraft that may not be fully public?
The North American X-15 holds the official world record for the fastest speed ever achieved by a crewed, powered aircraft. On October 3, 1967, USAF pilot William J. Knight reached Mach 6.7 (approximately 4,520 mph) — a record that remains unbroken. The X-15 was a rocket-powered experimental aircraft operated jointly by the U.S. Air Force and NASA, flying so high on some missions that it crossed the boundary of outer space and qualified several of its pilots as astronauts.
For jet-engine aircraft specifically, the Lockheed SR-71 Blackbird holds the official record.
