
Why a Mach 5 passenger plane is a crazy idea that might just work
CNN
Atlanta-based startup Hermeus hopes to develop a passenger airplane capable of reaching Mach 5, or 3,000 miles per hour, but is the prospect of building a hypersonic successor to Concorde merely a flight of fancy?
(CNN) — Almost two decades since Concorde retired, interest around supersonic travel has been picking up pace, and several super-fast planes are under development. Airlines seem interested: United has already committed itself to offering supersonic routes as early as 2029.
But what about hypersonic travel, which happens at speeds of Mach 5 -- five times the speed of sound -- and above? That would get an aircraft from New York to London in just 90 minutes, compared to about three hours for Concorde, and between six to seven hours for a regular passenger jet.
Is it even possible?

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