4. X-15 4,520mph
Photo: nasa
We’ve now reached the “hypersonic” aircraft section of the list with speeds almost incomprehensible. North American Aviation combined with the U.S. Air Force produced the X-15 Rocket that made its first flight in 1959 and could reach 4,520mph, a record for a manned aircraft that was set in 1967 by William J. Knight. Here we are almost 50 years later and that record is still untouched even with advancements in technology. Only three of these aircraft were made and they made a total of 199 flights before retiring in late 1968.