Air-breathing engine in Boeing's X-51A WaveRider may pave the way to Mach 20 planes

The Hypersonic X-51A WaveRider

Boeing's X-51A WaveRider — a jet-fueled, air-breathing hypersonic rocket developed for the U.S. Air Force  —  went hypersonic during a recent test off the Southern California coast, flying at more than five times the speed of sound.

A Silver Surfer-style, air-breathing engine defied naysayers with its triumphant recent test reaching Mach 5 -- that’s an astonishing mile per second, or nearly 4,000 miles per hour-- smashing its own previous time in flight record.

At Edwards Air Force Base on Wednesday, May 1, Boeing's WaveRider made the longest hypersonic flight to date, flying for three minutes and smashing its own 2010 record. The air-breathing engine that powered the X-51A WaveRider could be key not just to travelling coast to coast in under 40 minutes but to making the sort of deep-space exploration seen in "Star Trek: Into Darkness" a reality.

The government has high hopes for this type of hypersonic engine, and defense agency DARPA is looking to push the tech further, with plans to invest more than $90 million into the hypersonics programs over the next two years.

One goal is to provide global-range, maneuverable, hypersonic flight at a mind-warping Mach 20. In 2014, DARPA plans to launch the Small Responsive Space Access X-Plane to mature the technology inexpensively, for quick reaction not just anywhere on the globe but also in space.

DARPA wants this X-Plane to successfully undertake ten flights in ten days, carrying cargoes up to 5,000 pounds to low earth orbit at a speed of at least Mach 10. The goal is a system ten times cheaper as well, which the Agency proposes to transition to the Air Force, Navy and commercial sector.

The 'Silver Surfer,' coming soon
Often described as a surfboard that rides its own self-created sonic wave, the X-51A Waverider does look sort of like the Silver Surfer’s mode of travel. It’s actually an unmanned scramjet-powered experimental aircraft.

It weighs approximately 4,000 pounds with a fuel capacity about 270 pounds and currently has a ceiling of more than 70,000 feet.

Ordinary rocket engines tend to get their thrust from a high-pressure, high-velocity gas stream, resulting from the combustion of liquid oxidizer and a hydrogen fuel.

They require on-board oxygen in a big way because they tend to use it to combust the hydrogen fuel - and this gives you speeds up to around 10,000 mph.

For example, a space shuttle weighs about 165,000 pounds, but still needs to lug around an extra 1.36 million pounds of liquid oxygen.

No such albatross with these very promising air-breathing engines. The WaveRider’s engine doesn’t require its own oxygen supply and instead harvests the air as it flies through the atmosphere.

Due to the novel method of combustion, its current take-off doesn't look like a traditional Cape Canaveral launch. Instead it uses a booster rocket to get to hypersonic speed, before the scramjet takes over and does its stuff.

In 2010, the X-51A achieved a major aviation history landmark by making the longest-ever supersonic combustion scramjet-powered flight.

The following year, the second flight test vehicle encountered a problem while nearing Mach 5. The third test run last year also encountered some problems and the vehicle was lost.

This fourth test produced a triumph, successfully demonstrating not just the revolutionary engine, but also high temperature materials, airframe and engine integration at hypersonic speeds.

NASA's experimental unmanned NASA's X-43A scramjet still holds onto the bragging rights on the speed front, however. It set the world speed record for a jet-powered aircraft -- recognized by the Guinness Book of World Records -- at Mach 9.6, or nearly 7,000 mph.

Air-breathing engines unlock aviation’s future
WaveGlider’s recent record-setting is important not just for pushing the boundaries of what’s possible, but for further establishing the bedrock of the hypersonic tech of the future.

With air-breathing engines, future space travel could be faster and cheaper, in part due to the potential for reducing the absurdly heavy onboard liquid oxygen weight currently necessary to make that journey from earth to space.

Air-breathing engines could allow for far larger payloads revolutionizing cargo transport to space and between points at home.

On earth, the speed of U.S. Air Force aircraft could be unmatched, and commercial air travel immensely accelerated -- making the Concorde look positively prehistoric.

Pratt & Whitney is developing a suite of hypersonic propulsion system technologies that have defense potential well beyond aircraft. Missiles, high-speed weapons and advanced defense systems could all be enhanced by this sort of tech.

This next stage hypersonic speed could be very useful for time-critical missions, and give the U.S. unprecedented speed in global strike.

Ballet dancer turned defense specialist Allison Barrie has traveled around the world covering the military, terrorism, weapons advancements and life on the front line. You can reach her at wargames@foxnews.com or follow her on Twitter @Allison_Barrie.