The company with the world’s largest aircraft now has a hypersonic rocket plane

Stratolaunch has finally found a use for the world's largest airplane.

Twice in the last five months, the company launched a hypersonic vehicle over the Pacific Ocean, accelerated it to more than five times the speed of sound, and autonomously landed at Vandenberg Space Force Base in California. Stratolaunch used the same vehicle for both flights.

This is the first time anyone in the United States has flown a reusable hypersonic rocket plane since the last flight of the X-15, the iconic rocket-powered aircraft that pushed the envelope of high-altitude, high-speed flight 60 years ago.

Stratolaunch announced the results of its two most recent test flights Monday. In December and again in March, Stratolaunch's Talon-A2 rocket plane launched from the belly of an enormous carrier aircraft over the Pacific Ocean and flew several hundred miles to Vandenberg, a military spaceport about 140 miles northwest of Los Angeles. There ...