2013 Event A successor to the SR-71 Blackbird is being built by Lockheed Martin. The company's Advanced Development Programs, known by the alias Skunk Works, has taken on the challenge to builde the SR-72, capable of flying at mach 6 with expected delivery in 2023 1967 Event William Knight sets X-15 speed rec of 7,297 KPH/4,534 MPH/Mach 6.72 1959 Event USAF rocket-powered rail sled attains Mach 4.1 (4970 kph), New Mexico 1953 Event Chuck Yeager reaches Mach 2.43 in Bell X-1A rocket plane 1953 Event Scott Crossfield in Douglas Skyrocket, 1st to break Mach 2 (1,300 MPH) 1947 Event Chuck Yeager in Bell XS-1 makes 1st supersonic flight (Mach 1.015) 1916 Death Ernst Mach, Austrian physicist/philosopher/psychologist, dies at 78 1898 Event John Ames Sherman patents 1st envelope folding and gumming mach (Mass) 1895 Death Charles T Stork, great industrialist (cotton mach factory), dies at 73 1838 Birthday Ernst Mach, Chirlitz-Turas Austria, physicist/philosopher/psychologist
