Hypersonic missiles and space planes.

• Author: Magnuson, Stew

Hypersonic technology, which has been in development since the 1950s, holds the promise of sharply reducing the so-called tyranny of time and distance.

When the intelligence community tracks down a high value target such as a terrorist group leader having a meeting with his top lieutenants, commanders want the ability to send a missile his way before his tea grows cold.

Payloads on hypersonic aircraft, whether they are weapons or sensors, could reach their destination within minutes, rather than hours, said Mark Lewis, former chief scientist of the Air Force and now director of the Science and Technology Institute at the Institute for Defense Analyses, a federally funded research-and-development center.

"It could bring an important new capability to the military. ... It would be another arrow in the quiver," he said in an interview.

Hypersonic speed is generally defined as beginning at Mach 5, which is the point where aerodynamic heating caused by the speed of the vehicle cutting through the atmosphere becomes a factor.

The Air Force concluded its successful X-51 WaveRider program last year. The final test had the missile-like aircraft flying at Mach 5.1 for about 200 seconds.

Meanwhile, the Army is testing the advanced hypersonic weapon, a missile designed for vertical launch. It suffered a failed test seconds after takeoff in August, but that was caused by a faulty booster, not the missile or hypersonic technology itself Lewis noted.

What comes next is the question, Lewis said. The technology can be applied to both weapons and intelligence gathering. The first application is likely to be the former.

"You can imagine a hypersonic weapon on a relatively established bomber platform. You can imagine popping a hypersonic weapon off a Navy cruiser. Suddenly, you've taken an existing system and given it this new capability," he said.

Hypersonic technology could be seen as a follow-on to stealth, Lewis said. Even if an aircraft has that kind of technology, it doesn't mean it is invisible, he said. Adversaries are growing better at spotting stealthy aircraft, he said. Speed m ight compensate for that, he said. "If I can fly really fast, it makes it harder to act against me. It doesn't make it impossible. But it makes it harder."

Top Air Force leaders are indicating that they want to move hypersonic technology to the next level.

Air Force Chief of Staff Gen. Mark Welsh and Secretary Deborah Lee James in the document 'America's Air Force: A Call to...