Balky ISS Computer May Delay Monday's SpaceX CRS-3 Launch – UPDATE

UPDATE:  NASA will air a press conference on NASA TV at noon EDT on Sunday, April 13, with an update on the mission’s status.

NASA reported late last night (EDT) that a backup computer on the exterior of the International Space Station (ISS) is malfunctioning.  If the problem cannot be overcome by Monday, SpaceX’s CRS-3 cargo flight to the ISS could be delayed.

NASA posted on its website that the computer, called a Multiplexer-Demultiplexer (MDM), is not responding to commands.  MDMs control some of the systems associated with robotic systems like Canadarm2, which is needed to grapple SpaceX’s Dragon spacecraft and move it a docking port.  Canadarm2 itself is fine and the primary MDM also is fine.  Only the backup MDM is affected.

If NASA cannot get it to work, a spacewalk will be needed to replace it, NASA said. That would mean a delay in the SpaceX launch of its third operational cargo mission to ISS, CRS-3.

The launch was originally scheduled for March 16, but was delayed because of a fire at an Air Force radar tracking site at Cape Canaveral that also delayed a national security space launch.

In the meantime, NASA and SpaceX continue to work toward an on-time launch of SpaceX CRS-3 at 4:58 pm EDT on Monday.  If the launch proceeds as planned, SpaceX’s Dragon spacecraft would arrive at the ISS early Wednesday morning EDT.

Check back here for updates as they become available.