[sarex] STS-116 MCC Status Report #09

Arthur Rowe azrowe80 at verizon.net
Thu Dec 14 04:22:55 PST 2006


11:30 p.m. CST Wednesday, Dec. 13, 2006
Mission Control Center, Houston, Texas


STS-116 MCC Status Report #09

The first phase of the electrical and thermal makeover of the 
International Space Station was completed tonight as the outpost’s 
newest solar arrays began rotating to follow the sun and ammonia flowed 
into the station’s permanent cooling system for the first time.

Flight controllers sent commands to enable a large joint to begin 
rotating around 7 p.m. CST, moving the solar arrays on the P4 truss like 
a giant paddle wheel to track the sun as the station moves from daylight 
to darkness in orbit. A few hours later, just before 10 p.m. CST, valves 
were opened to allow 300 pounds of ammonia to flow into the truss 
segments of the station and its radiators, the first step toward 
providing permanent cooling for the avionics and electronics on the 

Those vital activation tasks occurred after a day-long effort by 
Discovery’s crew to retract the port array on the P6 solar array truss 
structure, which was installed six years ago to provide early electrical 
power for the station.

The crew spent six hours today sending as many as 45 commands in a 
start-stop fashion to retract, then redeploy, then retract the balky 
Venetian-blind like array panels in an effort to fold them into a narrow 
blanket box at the base of the array. But guide wires that help fold the 
arrays flat into the box apparently became snagged with only 17 out of 
31 bays of the port array retracted. That was enough, however, to 
provide enough clearance to enable the new P4 arrays to begin rotating 
as planned.

Mission managers met tonight to discuss various options for completing 
the P6 array retraction, and decided to press ahead with the second of 
three scheduled spacewalks Thursday by Bob Curbeam and Christer 
Fuglesang during which they will rewire the first pair of electrical 
channels for the permanent power system on the station.

Managers will convene over the next few days to determine whether 
additional spacewalk activity by Discovery’s crew will be scheduled to 
complete the retraction of the P6 array, although they have concluded 
that the array is in a safe configuration for the remainder of this 
mission, Discovery’s undocking next week, and if necessary, for the 
arrival of a new Russian Progress resupply ship in January should a 
spacewalking task be added to the Expedition 14 crew following 
Discovery’s flight.

Late tonight, to gather data for a future decision, Mission Control 
asked Discovery Commander Mark Polansky and Station Commander Mike 
Lopez-Alegria to consider which flight day would be best for a fourth 
spacewalk if one is ordered to complete the P6 array retraction. 
Polansky and Lopez-Alegria asked for more details about what such a 
spacewalk would entail before offering their thoughts.

With the station’s new solar arrays rotating and its permanent cooling 
system operating as advertised, Discovery’s crew members will begin an 
eight-hour sleep period at 1:17 a.m. CST and will wake up Thursday at 
9:17 a.m. CST to begin preparations for the second spacewalk of the 
flight. The station crew members will be awakened thirty minutes later.

The next STS-116 status report will be issued Thursday morning after 
crew wakeup, or earlier if events warrant.

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