Stratolaunch's massive twin-fuselage aircraft fires all of its 6 engines

The world's largest aircraft, coming from the house of Paul Allen's Stratolaunch Systems, has just cleared the first phase of its engine testing.

The enormous aircraft, which boasts two fuselages and a wingspan of 385ft (enough to cover a football field), fired all of its six Pratt & Whitney turbofan engines for the first time at the company's facility at the Mojave Air and Space Port in California.

Conducted in three phases, the engine test followed a well-defined build-up approach. Firstly, the team started with the dry motor test where they used an auxiliary power source to charge the engines.

Next came the wet motor, where fuel was introduced to the engines. Finally, they turned on each engine individually and allowed them to idle. All six delivered the expected results, according to the aerospace company.

Stratolaunch ultimately aims to use its megaplane as a launch platform to provide low-cost access to low Earth orbit. The company, founded in 2011, has designed the aircraft to carry rockets up to a certain altitude, where they would detach and fire engines to complete the rest of its space journey.

The one of a kind plane will have a maximum take-off weight of 1.3 million pounds and will carry a rocket (payloads up to 550,000 pounds) attached underneath the wing connecting its two fuselages.

The latest engine test comes as part of several tests Stratolaunch has been conducting in order to take its massive plane to the skies. Back in May, the aerospace giant moved the megaplane out of its hanger for the first time, to start the series of tests. Moving ahead, it will conduct more engine tests and taxi tests.

All these efforts suggest the company is closing in on that ultimate first flight, but for now, there's no fixed word on when we might see the behemoth of a plane cruising and carrying rockets into the sky.