The gargantuan Stratolaunch dual-fuselage aircraft, with a wingspan of 385 ft (117 m), is one step closer to reaching the skies after it recently completed a second taxi test that saw it hit a speed of 46 mph (74 km/h) as it stormed down a runway in Mojave, California.

Announced back in 2011, Stratolaunch Systems is one of several companies working to develop an air-launch-to-orbit aircraft. After years of development the massive plane first rolled out of its hangar and into the public eye last year and since then has rapidly moved through a series of successful testing phases ahead of a first flight planned for late 2019 or early 2020.

The first successful taxi test took place in December last year as the aircraft traveled under its own power down a runway reaching a speed of 28 mph (45 km/h). This allowed the engineers to monitor systems such as steering, braking, anti-skid and telemetry. Now the team has ramped up the speed to 46 mph (74 km/h) as revealed in a new video showing the enormous aircraft barreling down the runway powered by six Pratt & Whitney turbofan engines.

While no specific date has been announced for the next stage of testing, if the engineering team does eventually get this beast into the air it will be the largest plane to ever take flight. With a wingspan of 385 ft (117 m), the aircraft weighs an astonishing 500,000 lb (226,000 kg) and is designed to carry payloads up to 550,000 lb (249,476 kg).

Back in 2011, co-founder of Stratolaunch Systems Paul Allen commented, "We are at the dawn of radical change in the space launch industry." It may have seemed like an overly ambitious statement seven years ago, but after watching this mammoth engineering feat speed down a runway in 2018 it now feels like an entirely apt statement. We can't wait to see this thing get up into the air.

Source: Stratolaunch

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