KENNEDY SPACE CENTER, Fla. -- The launch of a commercial cargo ship making its first flight to the International Space Station is expected to slip a week or so to give engineers more time to complete pre-flight testing and analysis, Space Exploration Technologies, or SpaceX, announced late today.
The company had been aiming to launch its Falcon 9 rocket and Dragon cargo capsule on April 30. A second launch opportunity was available May 3.
Last week, NASA managers tentatively cleared the SpaceX rocket and capsule for launch pending completion of testing and a final review of open items and overnight Sunday, company founder and chief designer Elon Musk said in a Twitter posting: "Just completed the rocket rollout review at SpaceX HQ in California. Almost time to launch. Pucker factor increasing..."
But this afternoon, after a review of the Dragon systems, Musk tweeted: "Am pushing launch back approximately a week to do more testing on Dragon docking code. New date pending coordination with NASA."
Company spokeswoman Kirstin Brost Grantham said in a later e-mail: "After reviewing our recent progress, it was clear that we needed more time to finish hardware-in-the-loop testing and properly review and follow up on all data. While it is still possible that we could launch on May 3, it would be wise to add a few more days of margin in case things take longer than expected. As a result, our launch is likely to be pushed back by one week, pending coordination with NASA."
With the SpaceX slip, a United Launch Alliance Atlas 5 rocket carrying a military communications satellite valued at more than $1 billion, originally scheduled for takeoff May 5, has been moved up to May 3. Following standard practice, the Air Force Eastern Range, which provides tracking and telemetry support for all rockets launched from Florida, will give ULA at least two days to get the rocket off the ground and possibly three.
Because of time needed to reconfigure range systems to support a different launch vehicle, May 7 appears to be the earliest available launch date for the SpaceX Falcon 9. Because of space station rendezvous requirements, SpaceX cannot launch on May 8 or 9. A second opportunity apparently would be available May 10.
But it is not yet clear whether NASA would press ahead for a launch on May 10 and a berthing three days later given Russian plans to launch a Soyuz spacecraft with three fresh station crew members on May 14 U.S. time.
In any case, NASA and SpaceX are expected to announce a new target launch date later this week.