SpaceX CRS-4 Launch Slips One Day While ISS Joint Commission Worries About Delays

NASA announced today that the launch of SpaceX’s next cargo resupply mission to the International Space Station (ISS) has been delayed one day to September 20, 2014.  A one-day delay is minor, but at a recent meeting of the U.S.-Russian joint commission that oversees ISS safety and readiness issues, concern was expressed about delays in U.S. resupply missions.

NASA said the “adjustment” in the SpaceX CRS-4 launch date was made to accommodate preparations of SpaceX’s Falcon 9 rocket and “was coordinated with the station’s partners and managers.”  This is the fourth operational SpaceX cargo flight to the ISS (SpaceX CRS-4).  Launch is currently scheduled for 2:16 am ET on September 20 from Cape Canaveral, FL, and NASA has several pre- and post-launch briefings planned.  If the launch does, in fact, take place on September 20, berthing to the ISS will be on September 22.

In a June 20, 2014 letter to the heads of NASA and its Russian counterpart, Roscosmos, obtained by SpacePolicyOnline.com, the ISS Joint Commission (JC) expressed mild concern about schedule delays for U.S. “visiting vehicles” — SpaceX’s Dragon and Orbital Sciences Corporation’s Cygnus.  Dragon and Cygnus deliver supplies to ISS.

“While the ISS program has done a good job of managing the manifest to ensure no resupply issues, the JC observed that there continues to be schedule delays with the U.S. visiting vehicles.  Although this has not presented any problems to date, it should be monitored as the U.S. commercial resupply program matures,” it said.

The JC is co-chaired by Lt. Gen. Tom Stafford (ret.), who chairs NASA’s ISS Advisory Committee, and Alexander Milkovskiy, head of the Roscosmos Advisory Expert Council.  It met most recently in Korolev, Russia (outside Moscow) from June 16-20, 2014.  its task is to advise the NASA Administrator and Roscosmos Director on the safety and operational readiness of ISS. Milkovskiy is Director General of Russia’s TsNIIMash, the Central Research Institute of Machine Building.  Stafford is a legendary Apollo-era astronaut who flew on Gemini and Apollo missions and commanded the U.S. portion of the joint U.S.-Soviet Apollo-Soyuz Test Project (ASTP) mission in 1975.

SpaceX’s last launch to ISS in April was delayed several times due to technical and weather problems.  The technical issues included a helium leak discovered about one hour before a planned launch on April 14.  Orbital’s subsequent cargo mission, Orb-2, was delayed initially because of the SpaceX problems, and then because of a test failure of an engine similar to the one used for the Orb-2 launch.

ISS resupply is also provided by Russia (Progress), Europe (ATV) and Japan (HTV), but the letter mentioned only the U.S. vehicles as a matter of concern.  Europe’s final ATV mission, ATV-5, is currently docked to the ISS.