Space Exploration Technologies Corp.'s unmanned spacecraft is "back on track" to deliver cargo to the International Space Station after an engine malfunction, the company's chief executive officer said.
Elon Musk, head of the Hawthorne, California-based company known as SpaceX, announced the engine issue in a Twitter posting about a half hour after Friday's 10:10 a.m. launch of the Dragon craft from Cape Canaveral, Florida.
Three of the four groups of engines, known as thrusters, didn't initially activate. After the ship orbited in space for about five hours, SpaceX was able to turn on a second set and regain control, Musk said. The rest were activated later, he said.
"It looks like we're going to be back on track here," Musk said during a press conference organized by the National Aeronautics and Space Administration.
The ship was supposed to link up with the station Saturday. That rendezvous will take place Sunday, according to NASA's website.
The agency requires at least three sets of thrusters on the craft to be working to connect with the space station, according to Suffredini said.
Musk said a preliminary review suggests the malfunction may have stemmed from a blocked or stuck fuel valve. He announced Friday afternoon in a Twitter posting that the engines were coming back online.
"Pods 1 and 4 now online and thrusters engaged," he wrote. "Dragon transitioned from free drift to active control. Yes!!"
James Oberg, a space consultant in Dickinson, Texas, and a former mission-control specialist for NASA, described the malfunction as a "routine contingency" and one "that all good flight-control teams prepare for."
With one set of engines, the supply craft still managed to successfully deploy its solar arrays, which supply electrical power.
The craft was launched from a Falcon rocket. It is carrying more than 1,200 pounds of scientific experiments, food and other cargo. It's scheduled to return March 25 with more than 2,300 pounds of equipment.
The mission is the company's second regular cargo delivery and third trip to the space station. SpaceX completed its first resupply mission in October following a test flight in May. The company has a $1.6 billion contract with the NASA for at least a dozen resupply flights.
SpaceX's October mission also wasn't flawless. Less than two minutes after launch, one of the rocket's nine engines shut down. The failure caused the eventual loss of an Orbcomm Inc. satellite that was flying in the rocket as a secondary payload.
NASA is relying on SpaceX and Orbital Sciences Corp., based in Dulles, Virginia, to help resupply the station after retiring its shuttle fleet in 2011.
The agency depends on Russia to carry astronauts to space at about $63 million per seat. It wants companies such as SpaceX and Boeing Co. to eventually do that work.