Before the official opening of the Paris Air Show, Airbus parent company EADS revealed what it has in the works to be the successor to the Concorde jet: the Zero Emission Hypersonic Transportation plane, which could reach 3,125 miles per hour or 4 times the speed of sound (Mach 4) while producing only water. The hydrogen- and oxygen-powered ZEHST plane runs on seaweed and will carry 100 passengers from London to New York in only 1 hour.
The ZEHST plane will use jet engines to get itself off the ground, after which it will engage rocket engines to get up to speeds that actually take it above the atmosphere. Then, engines called ramjets will be used, which are currently used in missiles for speeds of over 1,000 mph but can’t be used from a standing start. These will take the plane to altitudes of 20 miles (the average passenger jet cruises at 6 miles). The hitch? This plane will take 40 years to build. While the technology to create the ZEHST plane is already available, the cost of creating a completely new kind of aircraft is in the billions, and a plane that only carries 100 passengers will have a hard time repaying that debt.
Via Daily Mail