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...