SpaceX Dragon crippled by glitch following launch to space station
By Alan Boyle, Science Editor, NBC News
The Falcon 9 made a problem-free ascent from its launch pad at Cape Canaveral Air Force Station in Florida at 10:10 a.m. ET. But a half-hour after launch, SpaceX's billionaire founder, Elon Musk, said in a Twitter update that controllers encountered a glitch involving the capsule's thrusters. "Issue with Dragon thruster pods," Musk wrote. "System inhibiting three of four [pods] from initializing. About to command inhibit override."paceX's Falcon 9 rocket successfully sent an unmanned Dragon capsule into orbit Friday for a cargo run to the International Space Station, but the Dragon's thruster system is crippled. The glitch has already forced a delay in the cargo craft's space station rendezvous.
In an email, Ra said the Dragon "experienced an issue with a propellant valve" after it achieved orbit.Each pod contains a grouping of thrusters that are used to guide the Dragon's course in orbit. Initially, SpaceX said it preferred to hold off on opening up the Dragon's power-generating solar arrays until at least two of the four thruster pods were operational. Later, SpaceX spokeswoman Christina Ra said that the solar arrays were deployed after overriding the onboard computer.
"One thruster pod is running," she said. "We are trying to bring up the remaining three. We did go ahead and get the solar arrays deployed. Once we get at least two pods running, we will begin a series of burns to get to station."
NASA said three operational thruster pods would be required for the Dragon's approach to the space station. More than three and a half hours after launch, NASA mission control told space station commander Kevin Ford that SpaceX was making progress on the Dragon's thruster problem, but not enough progress to allow for Saturday's scheduled rendezvous.
"We wish it gets fixed and gets up here to us," Ford replied. "That's really awesome they're working their way through the problems."
A news briefing is planned later Friday to discuss the status of what's scheduled to be a three-week resupply mission.
This is the third Dragon flight to the station: The first one, which took place last May, was a demonstration flight aimed at proving that California-based SpaceX could safely reach the space station, get hooked up, and then descend again to a splashdown. Last October's second flight marked the first of what's expected to be 12 resupply missions to the station, under the terms of a $1.6 billion contract with NASA. At that rate, each Dragon mission costs NASA about $133 million.
If the Dragon can proceed with the resupply mission, astronauts will use the station's robotic arm to grab the capsule from a distance of 10 meters (33 feet), and then pull it in to a port on the orbital outpost's Harmony module.
This Dragon contains more than 2,300 pounds (1,050 kilograms) of cargo, including experiments to study the growth of plants and mouse stem cells in zero-G. There are also spare parts for the station's air-recycling system, and a research freezer for preserving biological samples.
A similar freezer was loaded up with ice cream treats for the crew for last October's resupply mission, but this time, the goodies packed on the Dragon were "a little bit healthier," SpaceX President Gwynne Shotwell said. Although she wasn't specific about what the space station's six residents would be getting, she said the treats were coming fresh from an orchard owned by the father of one of SpaceX's employees.
The astronauts are due to open up the Dragon on the day after its arrival. It will take about three weeks to unload the craft, then load it up with more than 3,000 pounds (1,370 kilograms) of cargo for return to Earth. The original schedule called for the Dragon to be unberthed for a Pacific splashdown and recovery on March 25.
SpaceX's cargo flights are meant to fill the gap left by the retirement of NASA's space shuttle fleet in 2011. Another company, Orbital Science Corp., has a separate NASA contract to begin deliveries to the space station later this year. Cargo can also be delivered to the space station on Russian, Japanese and European transports, but only SpaceX currently has the capability to bring cargo back down.
SpaceX and two other companies, Sierra Nevada Corp. and the Boeing Co., are developing crew-capable spacecraft under a separate NASA program. Those spaceships could be ready for NASA's use as early as 2017. In the meantime, U.S. astronauts have to ride on Russian Soyuz capsules at a cost of about $60 million per seat.
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