WATCH: World's largest plane by wingspan takes flight
It's being billed as the world's largest airplane by wingspan.
The twin-fuselage six-engine jet was built by Stratolaunch, the company created by the late Microsoft co-founder Paul Allen.
The design of the plane will allow it to act as a flying launch pad for satellites.
The idea is to fly the plane to 10 km (6.2 miles) before releasing satellites into orbit.
Its 385 ft (117 m) wingspan is the length of an American football field.
On its maiden voyage, the aircraft flew up to nearly 4,600 metres while reaching speeds of almost 275 km/h.