Orbital Sciences Corporation is proceeding with operations to prepare their Cygnus spacecraft to launch on its first mission to deliver cargo to the International Space Station (ISS) on Dec. 19, despite the fact that NASA has yet to decide whether or not to delay the mission after discovering a malfunction in the space station’s starboard cooling Pump Module’s flow control valve last week.
The mission, Commerical Resupply Services Mission (Orb-1), will be the first of eight scheduled commercial cargo resupply missions by Orbital to the ISS under NASA’s Commercial Resupply Services (CRS) contract.
An accident on the ISS, however, has forced NASA to turn their focus from the pending launch to the malfunction on the ISS, and the agency will not green-light launching a new spacecraft to the ISS without completely understanding the severity of the situation first.
However, despite the hardware malfunction on the ISS, Orbital is proceeding with launch preparations so the company can hit their Dec. 19 launch target date—just in case NASA decides to hold off on sending Expedition 38 astronauts Rick Mastracchio and Michael Hopkins on a series of spacewalks to fix the problem.
NASA and Orbital Sciences issued the following statement this afternoon:
“NASA engineers continued efforts Sunday to regulate temperatures in one of two cooling loops on the International Space Station affected by the malfunction last week of a flow control valve in a cooling pump. Efforts overnight to fine-tune the position of an isolation valve associated with the flow control system in the Pump Module into a “sweet spot” to assist the faulty Flow Control Valve in regulating the affected cooling loop’s temperatures were still being evaluated as engineers continue to review the data, valve positioning techniques and additional methods of temperature management in the loop.”
So, while work continues on the ground to launch Orbital’s Antares rocket and Cygnus cargo craft from the Mid-Atlantic Regional Spaceport at Wallops Island, Va., this Thursday, ISS astronauts Mastracchio and Hopkins continue to prepare their spacesuits and other equipment in the Quest airlock—should they be called upon to conduct multiple spacewalks to replace the Pump Module as soon as Dec. 19.
NASA’s statement goes on to say, “The International Space Station Program continues to keep both options on the table pending further engineering analysis and troubleshooting efforts on the station’s cooling system.”
The space agency is expected to make their GO / NO GO decision on whether or not to launch Cygnus this Monday.
Orbital released the following statement on the company’s Facebook page Sunday afternoon:
“We have been authorized to load the final cargo for the International Space Station into the Cygnus spacecraft today. This cargo is about 95kg of time-sensitive materials consisting primarily of science payloads. We expect to finish loading the cargo later this afternoon. Installation of the Antares payload fairing is scheduled to occur on Monday.
Loading the final cargo allows us to continue to target a launch on December 19. However, NASA is still assessing the thermal control issue on the space station, and a final determination to launch has not yet been made.”
Cygnus will be delivering supplies and time-critical science cargo to the ISS—loading the spacecraft today (already delayed from Saturday) instead of waiting for NASA’s final GO/NO GO decision allows Orbital to preserve several days of launch opportunities beginning Thursday night at 9:19 p.m. EST. Once the cargo is finished loading in the Pressurized Cargo Module (PCM ) it will take 12 hours to perform all necessary closeout procedures on Cygnus, including operations to purge the air in the PCM, close the hatch, and perform leak checks. Installation of the Antares payload fairing, which encapsulates the spacecraft for launch, would follow on Monday, Dec. 16.
Should NASA green-light a Dec. 19 launch attempt, Orbital expects to roll their Antares rocket and Cygnus spacecraft to its launch pad in the pre-dawn hours of Dec. 17.
Stay with AmericaSpace for updates and full coverage of Orbital’s first mission to the ISS.
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