Lockheed Martin hopes to eventually make planes that can fly as much as 20 times the speed of sound

A plane that can fly six times as fast as sound is just years away, according to its manufacturers.

The new military plane would be able to fly around 4,500 miles per hour, according to defence firm Lockheed Martin.

Companies have long struggled to develop such quick aircraft. But new engineering developments might finally make it possible to break through those records.

The company hopes that the new plane is just one step on the way towards its ultimate aim of planes that can fly as much as 20 times the speed of sound, according to CNBC.

The new technology allows the planes to harness a stream of air that would be compressed as the plane flies forward. Usually, planes work by using fan blades to compress that air — but the new changes will allow it to do so much more quickly.

The technology means that the SR-72 might come into service in the 2030s.

As well as the engine systems, some previous planes have been held back by the materials they’re made of. The Concorde, for instance, could only fly around twice the speed of sound.

The new plane will avoid those problems by being coated in ceramic tiles, of the same kind that were on the Space Shuttle.