File photo of a five-segment ATK solid rocket booster on the company’s test stand in Promontory, Utah. The 154-foot booster, which is in development for NASA’s Space Launch System (SLS), will produce heat two-thirds the temperature of the sun, and its 12-foot-diameter cylinder will deliver 3.6 million pounds of thrust when the rocket ignites. The next full-scale test article for the SLS booster, Qualification Motor-1 (QM-1), is expected to ignite for a two-minute test fire on the morning of March 11, 2015. Photo Credit: ATK

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When NASA’s heavy-lift Space Launch System (SLS) rocket lofts the agency’s Orion deep space crew capsule for the first time in 2018 it will mark the beginning of a new chapter in America’s human spaceflight efforts, aiming for destinations beyond low-Earth orbit (LEO) by employing the largest and most powerful launch vehicle in history. The colossal 321-foot tall SLS will thunder towards space on the power of four former (upgraded) liquid-fueled space shuttle RS-25 engines, but even with a combined thrust of nearly 2.5 million pounds those four engines alone won’t be enough to provide the 70-metric-ton (77-ton) lift capacity the initial SLS configuration promises. The rocket needs more power at launch to make NASA’s ambitious deep-space human exploration plans a reality, and this spring ATK is expected to test fire the largest and most powerful solid rocket booster ever built to help get the job done.

Quelle: AS