Caution Prevails - Orbital Antares Launch to the ISS Postponed

©NASA/Bill Ingalls

File photo. January 9, 2014 Antares launch.

Although there are no issues with the current Orbital Antares rocket or the Cygnus spacecraft, both of which are ready to launch, it is with abundant precaution that the mission to the International Space Station has been postponed until no earlier than July 1.

It was a May 22nd failed hot-fire test of an Aerojet Rocketdyne AJ26 engine planned for a 2015 launch which created the delay in the latest Orbital resupply mission to the space station.

The AJ26 engine is a staple engine used by the Antares. Currently there is an ongoing investigation into what went wrong with hot-fire test. Once the investigation is concluded the launch should be able to proceed unless the investigation turns something up that warrants further delay.

In statement released today by Orbital they say "the new launch schedule reflects the timing of the investigation into the cause of an AJ26 engine failure that occurred in late May at NASA's Stennis Space Center during customary acceptance testing. All other elements of the Orb-2 mission are prepared to move forward, including the Cygnus spacecraft, which is fueled and, except for late-load cargo, is packed with its manifest of ISS cargo."

"The engine that failed was designated for use in a 2015 CRS mission and was undergoing hot fire testing that all Antares AJ26 engines are subject to in order to ensure nominal performance and acceptance for use in Antares missions. The investigation into the failure is being led by the Antares main stage propulsion supplier, Aerojet Rocketdyne, with Orbital and NASA engineers also supporting the effort. Once the investigation team reaches the point in their process that they can clear Antares to launch the Orb-2 mission, a targeted launch date will be established. For now, NET July 1 is simply a planning date. Please check back here for further updates."

Related: Orbital Antares Launch Postponed, May 28, 2014

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