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Initial tank pictures show no major foam loss BY WILLIAM HARWOOD STORY WRITTEN FOR CBS NEWS "SPACE PLACE" & USED WITH PERMISSION Posted: June 1, 2008 Close-up photos of the shuttle Discovery's external tank, shot as it drifted away from the orbiter Saturday, show a few relatively minor areas of foam loss but no major damage, NASA officials said today. Redesigned oxygen feedline brackets and new ice-frost ramps used to connect pressurization lines and a cable tray to the tank's skin - both recent post-Columbia safety upgrades - appeared to perform well. About five pieces of debris were seen falling away during launch from a camera mounted on the tank, but Mission Management Team Chairman LeRoy Cain said today it's not clear where the presumed foam might have originated.
"So those areas of foam that we saw coming off, those five or so pieces, at least some of them are coming from an area that we can't see yet or are not evidenced in the handheld or the umbilical well imagery that we've seen. So possibly from areas maybe underneath the feedline or areas that we're just not able to see because of the rotation of the tank and the lighting." External tank No. 128 was the first built from the ground up with post-Columbia upgrades, including the new feedline brackets and ice-frost ramps, redesigns intended to further minimize foam shedding. Based on video and still images shot by the astronauts, Cain said all of the feedline brackets were still in place as were the new ice-frost ramps. "We do have a couple of areas where we lost some foam ... but in a general sense, in a broader sense, the tank really performed in an absolutely magnificent fashion," he said. The photographs show a relatively small divot in the foam insulation just below the left bipod strut that helped hold the nose of the shuttle to the tank. A few other areas of foam loss also were noted, but Cain said engineers had not yet tried to synch up the damage sites visible in the still photos with the foam shedding incidents visible in the ascent video from the ET camera.
Along with downlinking post-separation video and still images today, shuttle pilot Kenneth Ham and Karen Nyberg used Discovery's robot arm to carry out a cursory inspection of the shuttle's upper wing leading edge panels and no obvious damage sites could be seen. A small corner of an insulation blanket on an aft rocket pod appeared to have pulled up slightly, but it did not seem significant. The astronauts were unable to carry out the usual flight day two inspection of the shuttle's nose cap and wing leading edge panels using a 50-foot-long boom equipped with laser scanners and high-resolution cameras. The shuttle's payload - the Japanese Kibo laboratory module - is so large the boom could not be mounted in the ship's cargo bay. The crew of the last station assembly crew left their boom on the station and Discovery's crew will retrieve it during a spacewalk Tuesday. The boom will be used later in the mission as usual. In the meantime, Cain said ascent video, sensor data, ET separation pictures, video from cameras mounted in the shuttle's solid-fuel boosters and photographs shot by the station crew during Discovery's approach Monday will give engineers the data they need to assess the health of the orbiter's heat shield. So far, despite the foam seen falling away during launch in the ET camera, NASA managers are pleased with the performance of the tank.
"So I think in short, we have to be very careful in trying to determine too much from that. And that's why you see us being kind of careful in our initial briefings. It is some indicator that we have some foam loss, and that's about it. We kind of rely on the other imagery data we have. In short, we have to be careful with that feedline camera and be very mature about how we handle what we see going up hill from that camera lens." Lead Flight Director Matt Abbott said Discovery is in good shape and ready for docking with the international space station on Monday. Because of an electrical problem with a backup steering system used by the left-side orbital maneuvering system rocket, the rendezvous will be completed using the right OMS engine and smaller maneuvering jets. The left-side engine is parked, but it will be used for re-entry at the end of the mission. For readers interested in a look ahead, here is the rendezvous timeline for Discovery's docking with the space station Monday (in EDT and mission elapsed time): DATE/EDT...DD...HH...MM...EVENT 06/02/08 10:34 AM...01...17...32...ISS in docking orientation 10:34 AM...01...17...32...Automated transfer vehicle solar arrays feathered 11:16 AM...01...18...14...Terminal initiation rocket firing 11:40 AM...01...18...38...U.S. solar arrays feathered 11:41 AM...01...18...39...Station in proximity operations mode 11:52 AM...01...18...50...Sunset 12:14 PM...01...19...12...Range: 10,000 feet 12:23 PM...01...19...21...Range: 5,000 feet 12:27 PM...01...19...25...Sunrise 12:29 PM...01...19...27...Range: 3,000 feet 12:33 PM...01...19...31...MC-4 rendezvous rocket firing 12:37 PM...01...19...35...Range: 1,500 feet 12:39 PM...01...19...37...Rotational pitch maneuver start window open 12:42 PM...01...19...40...Range: 1,000 feet 12:45 PM...01...19...43...KU antenna to low power 12:46 PM...01...19...44...+R bar arrival directly below ISS 12:51 PM...01...19...49...Range: 600 feet 12:53 PM...01...19...51...Start pitch maneuver 12:55 PM...01...19...53...Noon 01:01 PM...01...19...59...End pitch maneuver 01:03 PM...01...20...01...RPM full photo window close 01:04 PM...01...20...02...Begin move from below to in front of station (575 ft) 01:11 PM...01...20...09...RPM start window close 01:15 PM...01...20...13...+V bar arrival; 310 feet directly ahead of station 01:16 PM...01...20...14...Range: 300 feet 01:20 PM...01...20...18...Range: 250 feet 01:23 PM...01...20...21...Sunset 01:24 PM...01...20...22...Range: 200 feet 01:27 PM...01...20...25...Range: 170 feet 01:28 PM...01...20...26...Range: 150 feet 01:33 PM...01...20...31...Range: 100 feet 01:36 PM...01...20...34...Range: 75 feet 01:40 PM...01...20...38...Range: 50 feet 01:43 PM...01...20...41...Range: 30 feet; start stationkeeping 01:48 PM...01...20...46...End stationkeeping; push to dock 01:52 PM...01...20...50...Range: 10 feet 01:54 PM...01...20...52...DOCKING 01:58 PM...01...20...56...Sunrise
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VIDEO:
SUNDAY'S MISSION STATUS BRIEFING 