Shuttle Atlantis in Good Health for ISS Docking

This image, taken by an STS-115 astronauts just after reaching orbit, shows one area of ice frost ramp foam loss during Atlantis' Sept. 9, 2006 launch. None of the lost foam appeared to damage the orbiter. CREDIT: NASA/JSC.

HOUSTON - NASA's space shuttle Atlantis appears to be in good health as it ferries six astronauts and a hefty payload towards the International Space Station (ISS), mission managers said Sunday.

"We have a really good start to this very complex mission," John Shannon, head of Atlantis' STS-115 Mission Management Team, said in a briefing here at NASA's Johnson Space Center. "The teams certainly have their game faces on."

Commanded by veteran shuttle flyer Brent Jett, Atlantis' six-astronaut crew launched spaceward Saturday on an 11-day mission to outfit the ISS with a new pair of 17.5-ton port-side trusses and unfurl two wing-like solar panels. The space shuttle is scheduled to dock at the ISS at 6:46 a.m. EDT (1046 GMT) on Monday. [Watch the docking LIVE via SPACE.com's NASA TV feed here.]

"It was fun today, we got a big day tomorrow though," Jett told Mission Control at the end of his orbital work day. "So we've got to get some rest."

Jett and his STS-115 crewmates spent a busy day today scanning their spacecraft for any signs of damage from foam insulation debris, which fell from Atlantis' external tank late during launch well after they could have been a hazard concern. But initial analysis of imagery from the shuttle's sensor-tipped inspection boom has found no blemishes of concern, Shannon said.

"Atlantis looks great," Shannon said, adding that aside from a few minor glitches the orbiter is performing as expected.

A couple of microswitches for automated motors that open Atlantis' shell-like payload bay doors did not return proper signals, but are part of a redundant system with adequate backups, Shannon said. Engineers also found that one of four hydraulic system channels for the speed brake that pops out of Atlantis' tail during landing was also acting up, but has three redundant channels, he added.

Pinpointing foam loss

Image analysts have been able to pinpoint where some foam insulation fell free from Atlantis' external tank during launch using images taken by the shuttle's crew. NASA official reported several instances of foam debris shedding during the shuttle's 8.5-minute flight to orbit, but none at a time when they could pose a threat to Atlantis' vital heat shield.

Shannon said an early look shows that small pieces of foam fell from at least one insulated bracket - known as an ice frost ramp - while another bit originated near a similar structure. Ice frost ramps are known to shed some foam during liftoff, and the new data from STS-115's external tank will be rolled into a redesign of the ramps already underway.

"I would say the ice frost ramps performed exactly as we expected them to...there were no surprises on this flight at all," Shannon said, adding that another bit of foam fell from an area repaired later in the tank's preparations. "I think it will provide some good data for the team that's doing the redesign."

Atlantis' STS-115 mission marks NASA's second to fly with exposed ice frost ramps after engineers removed a protective, foam-covered wind screen after a large piece fell from the shuttle Discovery's fuel tank during 2005's STS-114 launch. Foam shedding during liftoff has been a prime focus for NASA since 2003, when a chunk of insulation pierced the heat shield of Columbia during launch and critically damaged the spacecraft, which was later lost with its crew during reentry.

Post launch heat shield inspections are now standard task in NASA's shuttle flight plan, and the integrity of Atlantis' precious heat-resistant tiles and carbon-composite panels has been deemed "not suspect", Shannon said.

Space station beckons

Meanwhile, Atlantis six-astronaut crew is bearing down on the ISS with its $371.8-million cargo of solar arrays and the Port 3/Port 4 truss segments to be attached to the orbital laboratory during the STS-115 mission.

Aboard the space station, Expedition 13 commander Pavel Vinogradov and flight engineers Jeffrey Williams and Thomas Reiter have readied their orbital home for its second visiting shuttle in three months. NASA's Discovery orbiter ferried Reiter and fresh supplies to the ISS in July's STS-121 mission.

"It's like preparing your house for a bunch of relatives to come over people who are also going to help you build the house while they're staying with you," said NASA's Kirk Shireman, who chairs the ISS Mission Management Team for the STS-115 spaceflight.

Atlantis' Monday docking will mark the delivery of the first major piece of ISS hardware since late 2002. Construction of the orbital laboratory stalled as NASA recovered from the Columbia accident.

"Tomorrow is an extremely busy day and a very big day for the International Space Station," Shireman said.

NASA will broadcast Monday's docking of the Atlantis shuttle at the ISS live, with rendezvous operations beginning at 1:35 a.m. EDT (0535 GMT). You are invited to follow the shuttle's progress using SPACE.com's NASA TV feed by clicking here.

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