CAPE CANAVERAL, Fla. -- NASA is confident SpaceX can safely launch another International Space Station resupply mission on March 1, although a joint investigation into an engine failure last fall is not yet closed.
All indications are that the next set of Falcon 9 rocket engines are "good to go," said Mike Suffredini, NASA's ISS program manager, during a Thursday news conference updating the status of station systems and activity.
The Merlin engine that shut down 79 seconds into an Oct. 7 launch had undergone considerable pre-flight testing, though not beyond levels it was designed to handle.
Investigators think that extra testing may have contributed to a pressure chamber breach, Suffredini said.
Debris shot from the bottom of the rocket, prompting speculation the engine had exploded.
In fact, SpaceX said the engine -- one of nine powering the rocket's first stage -- shut down as designed and sensors continued to record data. And the debris was likely from an aerodynamic cover shattered by the release of pressure.
A Dragon cargo spacecraft visited the space station as planned, but a small communications satellite failed to reach its intended orbit.
Suffredini said engineers had reviewed a huge amount of data but not produced a "specific smoking gun," which he said is not uncommon when investigating systems cannot be recovered.
The next engines in line to fly have been inspected thoroughly, and none has been tested beyond the levels needed to certify them for flight.
"We've been deeply involved and are completely satisfied that the right amount of work has been done on these systems," Suffredini said.
Suffredini also reported Orbital Sciences Corp. is making progress toward key tests of its new Antares rocket and Cygnus spacecraft, which hopefully will start delivering cargo this year.
A test-firing of the rocket's main engines is planned late this month, to be followed by a test launch in the spring and a demonstration mission this summer that will attempt to berth a Cygnus at the station.
"They've overcome a number of hurdles, and so I think the schedule is starting to stabilize on that system, so we're looking forward to it coming to ISS as well," Suffredini said.
If that schedule holds, the next station crew, set to launch March 27 from Kazakhstan in a Soyuz spacecraft, could see visits by all six international and commercial spacecraft that fly to the station.
"It's shaping up to be a really exciting expedition," said NASA astronaut Chris Cassidy, a U.S. Navy SEAL and veteran of a 2009 shuttle flight, who will launch with two Russian cosmonauts. "We've got a lot going on."
During Cassidy's more than five-month expedition, Russian crew members plan to perform four spacewalks.
NASA also is considering up to three spacewalks to take care of a variety of maintenance tasks, including replacement of a failed communications device that sends and receives video and data from the ground.
Station managers are also studying whether to make Cassidy's crew the first to fly an express Soyuz trip to the station, arriving after just four orbits rather than the normal two-day journey.
"I think this is a very good thing that we are decreasing the time that it takes for crews to reach the ISS," said veteran cosmonaut Pavel Vinogradov, one of Cassidy's crewmates. "I don't anticipate any technical issues associated with this activity."
By James Dean, Florida Today