US military is planning a hypersonic vehicle that could fly from New York to London at five times the speed of sound.

The proposed hypersonic vehicle is based on the X51-WaveRider, a scramjet engine developed by the Air Force Research Laboratory and Darpa (the US military’s research agency) as part of a $300 million (£200 million) programme to prove the viability of air-breathing, high-speed scramjet propulsion.

Hypersonic flight is five times the speed of sound (Mach 5) and requires a special type of engine that can handle the heat and pressure of hypersonic aerodynamics.

Over the course of the WaveRider project four X-51A cruisers were built and in May 2010 the first X-51A WaveRider made a successful test flight off the coast of South California.

As it is effectively only an engine, it wasn’t capable of flight, so it was attached like a missile to the left wing of a B52 Stratofortress (below).

Military plane flying through blue sky with vehicle attached

When the B52 reached 50,000ft, the WaveRider was released, accelerating using a rocket booster before the engine ignited and it reached speeds of Mach 5.  A vehicle error after 200 seconds caused the flight to be terminated.

The last test flight was undertaken in May 2013, with the fourth X-51A WaveRider travelling 230 miles in just over six minutes – the longest air-breathing hypersonic flight - before it crashed into the ocean.

Check out video of the flight by clicking the arrow in the main picture above.

Air Force Chief Scientist Mica Endsley told Miltary.com that the X-51 was a proof of test concept.

“It showed that you could get a scram jet engine, launch it off an aircraft and it could go hypersonic,” she said.

“It was able to go more than Mach 5 until it ran out of fuel. It was a very successful test of an airborne hypersonic weapons system.”

Vehicle attached to military plane

The team is now planning a new type of hypersonic air vehicle capable of carrying equipment such as guidance systems and weapons. The challenge is to create materials, such as a guidance system, that will withstand the temperature, which they hope to overcome by 2023.

“There are a bunch of technological challenges that have to be addressed to make a functioning system that will work," Endsley said.

She said a flight from New York to Los Angeles could drop in time from 5 hours to 30 minutes.

Having the capability to travel long distances at high speeds makes hypersonic flight a key military technology of the future, with both the US and China testing hypersonic flights.

But don’t start planning your one-hour flight to the Big Apple just yet. Although hypersonic flight is possible, the human body isn’t capable of withstanding the current acceleration speeds.

Video credit: Boeing

Photo credit: Wright Patterson Air-Force Base