New | New Lockheed Martin jet heralds dawn of the hypersonic age

In aviation, being bigger isn’t always better. Despite being the undisputed giants of the modern age, neither Boeing’s 787 Dreamliner  nor the massive Airbus A380  are particularly inspiring; don’t we all yearn for a return of the supersonic age? 

Those who pine for the turbojet-powered Concorde,  which retired 10 years ago after taking more than 2.5 million passengers on regular 3½ hour crossings from New York to London, can now look forward to an age not of supersonic, but hypersonic aircraft. It looks set to make Concorde look like the 1960s technology it was.

Lockheed Martin’s new prototype SR-72 jet  – though just a two-seater for now – can theoretically travel from New York to London in  under an hour, reaching speeds of up to Mach 6 – about 7,350km/h,  or roughly  six times the speed of sound. Concorde travelled at a top speed of  2,173km/h, just under Mach 2. 

Despite the popular lament  at Concorde’s premature demise, it’s not that trailblazer  that the SR-72 has to live up to. The SR-72 comes from the same legendary Skunk Works  division of Lockheed Martin that in 1964 developed the SR-71 Blackbird,  a two-seater that remains one of the fastest aircraft built to date. Capable of  Mach 3, the SR-71 – which was used for spying until 1990 – flew from New York to London in less than two hours % in 1976.

It also holds the record for travelling between Los Angeles and Washington DC in just over an hour. 

Seven years in development so far, the similarly two-seater, twin-engine SR-72 can maintain such incredible hypersonic speeds because of its use of a scramjet supersonic combustion engine, which “breathes” compressed air, though to get to the very high speeds requires a regular turbine engine.

Joining the two separate systems together – the “combined cycle propulsion” concept – is the neat trick inside the SR-72.