NASA SLS Main Engine Test Fire

The most efficient rocket engine in history came to life again August 13, 2015 under clear skies, unleashing over a half-million pounds of thrust and a thunderous roar across southern Mississippi and NASA’s Stennis Space Center during a 535-second test fire. The same engine that powered the space shuttle uphill so reliably for three decades, Aerojet Rocketdyne’s RS-25, will again be employed for NASA’s enormous Space Launch System (SLS) rocket, upgraded to meet the new requirements for what will become the most powerful rocket in history.