The fourth and final X-51A Waverider hypersonic plane was tested this week by the U.S. Air Force off the coast of California.
The Air Force said in a statement Friday that the unmanned craft flew for more than three minutes under power from its supersonic combustion ramjet engine ("scramjet") hitting a speed of Mach 5.1
What happens when a scramjet engine is activated?
Imagine "lighting a match in a hurricane and keeping it lit," says Boeing in a video released Friday.
The WaveRider was released Wednesday from a B-52 bomber 50,000 feet above the Pacific and was initially accelerated by a rocket before the scramjet kicked in. The flight ended with a planned plummet into the Pacific Ocean.
Says the U.S. Air Force:
The final flight of the X-51A Waverider test program has accomplished a breakthrough in the development of flight reaching Mach 5.1 over the Pacific Ocean on May 1 a little after 10 a.m. Pacific Time.
"It was a full mission success," said Charlie Brink, X-51A program manager for the Air Force Research Laboratory Aerospace Systems Directorate.
The cruiser traveled over 230 nautical miles in just over six minutes over the Point Mugu Naval Air Warfare Center Sea Range. It was the longest of the four X-51A test flights and the longest air-breathing hypersonic flight ever.
Hypersonic technology could allow for an Air Force strike anywhere in the world within minutes. Previous test flights proved somewhat unsuccessful.
The third unmanned, experimental plane failed to fly last August after being dropped from a B-52 bomber at Point Mugu. At six times the speed of the splash, the one-time-use, Boeing-built bullet crashed into the ocean instead of shooting through the sky in an attempt to reach Mach 6.
Test two ended prematurely in 2011 with the craft trying to restart its engine. The first craft achieved Mach 5 for about 140 seconds in 2010.