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By the numbers: NASA's Space Launch System

Posted: September 14, 2011

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Billed as the biggest rocket ever built, NASA's concept for a behemoth heavy-lift booster unveiled Wednesday will initially weigh 5.5 million pounds, stand taller than the Statue of Liberty and generate 10 percent more thrust than the Saturn 5 moon rocket produced at liftoff.

The Space Launch System would be the biggest rocket ever built. Credit: NASA
Powered from the launch pad on its first flight by two solid rocket boosters and three hydrogen-fueled main engines, the Space Launch System would initially haul 70 metric tons, or about 154,000 pounds, of payload into low Earth orbit. That's more than double the lift capacity of any operational launch vehicle today.

NASA says it will cost $10 billion to design and develop the mega-booster in time for its first test launch by the end of 2017. It will cost another $6 billion to get the Orion capsule, or Multi-Purpose Crew Vehicle, ready for flight. Modifications and upgrades to launch infrastructure at the Kennedy Space Center in Florida will cost $2 billion more.

The twin five-segment solid rocket motors and three RS-25D/E engines are derived from equipment used on the space shuttle program. It's likely the early missions of the enormous rocket would fly with hardware that helped launch space shuttles.

NASA plans to plug its existing inventory of space shuttle main engines for the first few heavy-lift rocket flights. The engines are designed to be reusable, but they would crash back to Earth and be destroyed with the launcher's 27.5-foot-diameter core stage on SLS missions.

In its earliest crew configuration, the super rocket will stand 320 feet tall and weigh as much as 24 fully-loaded Boeing 747 jumbo jets. Its three main engines and pair of boosters will ramp up to 8.4 million pounds of chest-thumping thrust at liftoff, more than than the Saturn 5 moon rocket or the space shuttle.

That thrust level is equivalent to the horsepower of 160,000 Chevrolet Corvette engines, according to NASA.

With the addition of two more RD-25D/E engines on the first stage, the Space Launch System's "evolved" architecture would be able to deliver 130 metric tons, or 286,000 pounds, of mass to low Earth orbit. Its voluminous nose fairing would carry 9 school buses into space.

Its mass would increase to 6.5 million pounds and it would stand as tall as a 40-story building. The extra propulsion would raise its liftoff thrust to 9.2 million pounds, 20 percent more than the Saturn 5 rocket's powerful F-1 first stage engines.