Selasa, 06 Januari 2015

To Reuse Rockets, SpaceX Needs to Stick This Landing

If space tourism is ever going to become a reality for the general public, someone will need to devise a way to make spacecraft fly much more like airplanes than like existing rockets.

Elon Musk wants to be that someone. His Space Exploration Technologies (SpaceX) will try to land its Falcon 9 rocket aboard a floating platform 200 miles off the eastern coast of Florida on Tuesday, shortly after the launch of the company’s fifth cargo mission to the International Space Station (ISS). While SpaceX’s customer, NASA, cares primarily about the 5,200 pounds of supplies, tools, and science experiments—and an Imax camera—headed to the ISS, SpaceX is eager to make history retrieving a used rocket.

“A fully reusable vehicle has never been done before,” Musk said on the company’s website. “That really is the fundamental breakthrough needed to revolutionize access to space.” The SpaceX chief executive officer has said the development of a “rapidly reusable space launch vehicle” could reduce the cost of spaceflight by a factor of 100. That money-saving feat is also a key step in Musk’s goal of seeing humans migrate to Mars.

NASA’s space shuttle program employed a launch system that wasn’t particularly reusable. A craft’s two solid rocket-fuel boosters were fished from the ocean and refurbished; a shuttle’s larger external tank carrying liquid hydrogen was discarded. And while shuttles landed in California or Florida, they required an enormous amount of costly engineering work before taking a subsequent flight.

In 2014, SpaceX achieved a “soft landing” in the ocean on two Falcon 9 tests, but with an accuracy of only about 6 miles. The company is trying to improve that to within 32 feet on Tuesday’s landing. SpaceX is prepared for its precision landing to fail, putting the odds at “50 percent at best” given the technical hurdles of slowing the 14-story-tall rocket from a speed of about 1 mile per second and then setting it gently on a floating drone ship platform that’s 300 feet by 170 feet. “Stabilizing the Falcon 9 first stage for reentry is like trying to balance a rubber broomstick on your hand in the middle of a wind storm,” the company said in a news release last month, shortly before it delayed the launch into the new year.

Regardless of how Tuesday’s landing attempt fares, California-based SpaceX is probably still several years away from perfecting a reusable launch system for commercial customers, says Marco Caceres, a senior space analyst with Teal Group in Fairfax, Va. But SpaceX has already disrupted pricing, with its Falcon 9 launches costing $61.2 million—the lowest in the industry. The company could further lower prices by as much as one-third if it mastered the technology of reusable rockets, Caceres says. SpaceX competes in the space launch market with companies such as United Launch Alliance, a Boeing-Lockheed Martin joint venture; the European consortium Arianespace; and Orbital Sciences.

“There’s nothing that says the price that has been set—$60 million or $70 million per launch—that that’s what it has to be if you can come up with reusable technologies that are proven and that are safe,” Caceres says. Lower prices would also lead to more customers that want to use satellites, such as universities, but can’t afford current launches, he says. And a stream of new customers would further boost SpaceX’s coffers to help fund its many future aspirations, such as flights to Mars and back.

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