NASA studying chipped tile, debris from fuel tank
BY WILLIAM HARWOOD
STORY WRITTEN FOR CBS NEWS "SPACE PLACE" & USED WITH PERMISSION
Posted: July 26, 2005
KENNEDY SPACE CENTER, Fla. - The shuttle Discovery, carrying seven astronauts, critical space station supplies and the hopes of a nation, rocketed into orbit today in a nerve-wracking bid to revive America's human space program two-and-a-half years after the Columbia disaster. But at least two pieces of debris seen falling from the shuttle shortly after launch brought back haunting memories of Columbia, prompting intensive analysis to determine what, if any, threat they might pose.
But a major goal of NASA's post-Columbia recovery effort was to minimize the amount of foam, ice or tile debris that can shake off during launch, possibly hitting and damaging the orbiter. The incidents seen today were captured by a new camera mounted on the external tank.
What might have caused the landing gear door tile to break, or how significant it might turn out to be, was not immediately clear. Likewise, engineers had no immediate explanation for the debris that appeared to originate from the fuel tank.
"This is a test flight and we're seeing areas of the vehicle working in flight regions that we have never seen before," said John Shannon, mission operations manager at the Johnson Space Center. "We've never seen the underside of the orbiter like that."
Closer to the ground, launch pad cameras caught a bird hitting the tip of the external tank a few seconds after blastoff. But it was a relatively low-speed collision and while it was no doubt a significant event for the bird, it caused no obvious damage to the shuttle.
Click here to see pictures from the bird strike, chipped tile and tank debris events.
In any case, Shannon said it would take several days to fully analyze all the available imagery to determine what, if anything, might need to be done about the tile damage or any other areas of potential concern.
"I don't have any conclusions because we're in the first half day of a six-day activity," he said. "We're going to get better data."
"We know the folks back on the planet Earth are just feeling great right now and our thanks to everybody for all of the super work that's been down over the past two-and-a-half years to get us flying again," she radioed after reaching orbit. "That was by far the smoothest ascent ... that we've ever experienced. (You) couldn't ask for a better flight."
Later, addressing the flight control team, Collins paid tribute to "the great ship Columbia and her inspiring crew."
"We miss them and we are continuing their mission," she said. "God bless them tonight and God bless their families. Good night."
With Collins and pilot James "Vegas" Kelly at the controls, Discovery's three hydrogen-fueled main engines shuddered to life at 10:39 a.m., throttling up to full power with a rush of flame and thunder.
Six-point-six seconds later, with the spacecraft straining against massive hold-down posts, the shuttle's two solid-fuel boosters ignited with a crackling roar, eight explosive bolts detonated and the spaceplane majestically vaulted skyward from launch pad 39B.
Climbing straight up atop twin jets of bright-orange 5,000-degree flame, Discovery rolled about its vertical axis and lined up on a trajectory paralleling the East Coast, the crew in a heads-down position beneath the ship's huge external tank.
It was a thrilling moment for thousands of area residents, tourists and countless engineers and technicians who worked virtually around the clock through weekends and holidays to recover from the Feb. 1, 2003, Columbia disaster and, more recently, problems with a fuel tank sensor that blocked a July 13 launch attempt.
Despite extensive troubleshooting, engineers were never able to pin down exactly what went wrong. But based on the results of the testing and additional checks built into today's countdown, NASA managers were prepared to waive a launch commit criterion to permit a launch with three operational sensors.
Debate about changing the rule in the heat of a flight campaign reminded many observers of schedule-driven management failures cited by the Columbia Accident Investigation Board. But top shuttle managers said safety was never at risk in today's campaign and that the decision to proceed was based on a solid understanding of the problem.
As it turned out, all four sensors worked flawlessly today, the launch rule was not changed and Discovery was cleared for flight as is.
Even so, memories of Columbia's Feb. 1, 2003, destruction - triggered by the impact of foam debris 81.7 seconds after launch 16 days earlier - were never far from mind as Discovery roared away through a partly cloudy sky. The shuttle's powerful booster rockets were jettisoned as planned two minutes and five seconds after liftoff, falling back to Earth as the shuttle smoothly accelerated toward space.
The debris incidents generated quite a bit of interest at the Johnson Space Center, but Shannon said it was premature to draw any conclusions. He said the tile damage appeared about an inch-and-a-half across, but analysts do not yet have any information on how deep the damage might be and thus, whether or not it poses any threat to the space shuttle.
As for the debris seen flying off the external tank a little more than one minute later, Shannon said it was not yet clear whether a piece of foam broke away, whether the event was associated with the booster separation sequence or whether it represented an unknown phenomenon that has not been previously seen.
But minimizing debris shedding was a major goal of NASA's post-Columbia recovery and more than 112 television cameras, high-speed film and movie cameras and powerful radars were focused on Discovery as it climbed away, giving engineers unprecedented views of the craft.
Two WB-57 jet aircraft, flying to either side of the shuttle's ground track at an altitude of 60,000 feet, used nose-cone mounted telescopes and high-definition TV cameras to monitor the shuttle through booster separation. The video offered a unique, never-before-seen perspective of a shuttle launch, but the debris events under discussion were not obvious in a video replay.
Earlier today, NASA Administrator Michael Griffin urged reporters to give the image analysis team time to do its work.
"Our guys are going to take a really serious look at the end-to-end footage and in fact, a danger would be possibly seeing something that's very large and visible that we haven't had a chance to look at and ignore something that would be smaller and more significant.
"The guys are going to take a professional look at every frame of footage that we have from every camera that we have. Because as I've said, these are test flights right now. The primary object under test is the external tank and all of the design changes we made to that tank so we'd never have a repeat of (Columbia)."
It will take engineers several days to review all the launch imagery, data from new impact sensors in Discovery's wings and to conduct extensive inspections in orbit using a new TV/laser scanning device and cameras aboard the international space station.
Engineers fully expected to see signs of impact damage even though the shuttle's external tank has been redesigned to minimize ice formation and foam shedding. But if any major damage is, in fact, detected, flight controllers are spring loaded to carry out additional inspections to precisely characterize the damage before considering what, if anything, might need to be done.
Unlike Columbia's ill-fated crew, the Discovery astronauts are equipped with rudimentary repair equipment that will be tested during the first of three planned spacewalks after docking with the international space station Friday. But it is doubtful NASA would ask a crew to rely on untried repair procedures if serious damage is, in fact, detected.
In a worst-case scenario, Collins and company more likely would be asked to move into the space station to await rescue by another shuttle crew. In that scenario, Discovery would be undocked by remote control from the Johnson Space Center in Houston and guided to an unmanned re-entry and breakup over the Pacific Ocean.
But NASA managers - and the astronauts - were confident the tank redesigns would be up to the task, allowing them to focus on the goals of the long-awaited mission.
"There will be debris, there will be some damage, I'm convinced of that," Discovery's flight engineer, Stephen Robinson, told CBS News before launch. "If there isn't, that'll be great but I'll sure be surprised. I would be very surprised if it's critical damage, damage that won't allow us to fly home on. But here's the thing. We'll know it. We won't have to wonder. We'll know it.
"We'll have the technology now for the first time on this mission to take a look at it with all the cameras and sensors. This is the way we verify all the engineering that's been done. So we'll get to look at our bird before we come home.
"Then, on top of that, if the worst on worst on worst happens and we do have critical damage, the space station will (be available for safe haven), we won't have to risk our lives coming back through the atmosphere. This is what gives me tremendous confidence and makes me feel very lucky I'm flying now."
Joining Collins, Kelly and Robinson aboard Discovery were Andrew Thomas, Wendy Lawrence, Charles Camarda and Japanese astronaut Soichi Noguchi. The goal of the 114th shuttle mission is to deliver critical supplies and equipment to the space station; to bring no-longer-needed hardware and trash back to Earth; to test rudimentary tile and wing leading edge repair techniques; and to install a new gyroscope in the space station's orientation control system.
The gyro installation, heat shield repair tests and work to attach tools needed for upcoming station assembly flights will be carried out during three spacewalks later in the mission.
But the first item on the agenda after reaching orbit was for Noguchi to photograph Discovery's empty external fuel tank as it drifted away to find out if any foam insulation came off during the climb to space.
Data collected from scores of impact sensors mounted behind the shuttle's reinforced carbon carbon wing leading edge panels was downlinked to flight controllers late in the day for detailed analysis.
The astronauts plan to spend all day Wednesday inspecting the exterior of the leading edge panels, the RCC nose cap and heat-shield tiles around the crew cabin for any signs of impact damage, either due to ice or foam.
Columbia was destroyed during re-entry because of a hole in an RCC panel on its left wing, which allow super-heated air to burn its way inside as the ship plunged back into Earth's atmosphere. The wing melted from the inside out, triggering Columbia's breakup.
Lost in the disaster were commander Rick Husband, pilot William "Willie" McCool, flight engineer Kalpana Chawla, David Brown, Michael Anderson, Laurel Clark and Israeli astronaut Ilan Ramon.
The Columbia Accident Investigation Board blamed the disaster on the separation of a suitcase-sized chunk of foam from an aerodynamically shaped ramp intended to prevent ice from building up around the struts holding the shuttle's nose to the external tank. A large piece of insulation from the same area broke away from a shuttle two missions earlier. But NASA managers concluded it did not represent a safety-of-flight issue and cleared the next two missions for launch while a fix was designed.
The accident board faulted that decision, saying NASA managers never recognized the threat posed by foam debris and instead had come to accept debris shedding as normal. Minor foam impact damage was seen on every flight even though NASA's original design criteria called for a debris-free fuel tank.
The accident board also found fault with how NASA responded to the launch-day strike on Columbia, saying poor communications and the agency's institutional "culture" prevented concerns from lower-level engineers from reaching senior managers. Those managers concluded Columbia could safely re-enter "as is" and never ordered spy satellite photographs that might have revealed the full extent of the damage.
Most engineers believe Columbia's crew could not have been saved even if those steps had been taken, but many fault agency management for not giving the team a chance to come up with a solution.
The Columbia Accident Investigation Board made 29 recommendations for improving management and flight safety, including 15 that had to be implemented before the shuttle program could resume missions. An independent panel of experts ultimately concluded NASA had fully implemented 12 of the recommendations but had fallen short on the three most critical requirements: eliminating all debris shedding from the external tank; initiating a program to strengthen the tiles and RCC panels to make them more resistent to impacts; and developing reliable tile and RCC repair techniques to cope with any damage that might occur.
But over the past two-and-a-half years, NASA has learned that it is impossible to eliminate all debris from the tank given its current design. A program to strengthen the leading edge panels was canceled after President Bush ordered the agency to retire the shuttle fleet by 2010. And in a sort of "Catch-22," NASA was unable to develop reliable repair procedures without first testing them in space.
But the review panel did not suggest NASA should not launch Discovery, merely that the recommendations, as written, were not fully implemented. Retired Adm. Harold Gehman, chairman of the Columbia Accident Investigation Board, agreed NASA had met the intent of the recommendations and "I know of no reason why they should not proceed with the launch."
For his part, Griffin said NASA had done everything humanly possible to fix the shuttle program's shortcomings and that any additional delay would only produce incremental improvements in safety.
"If we ground the shuttle fleet, we're not going to be able to complete station assembly, we're not going to be able to do other things that we want to do," he said before launch. "If, of course, we believe that all debris sources have been reduced to a level low enough that the shuttle outer mold lines won't be damaged, then the tile repair issue becomes kind of moot.
"We're in that gray area where we believe we have greatly reduced the risk due to debris, foam and ice, but not so much we're completely comfortable with it. So the STS-114 crew ... will be lifting off in the face of a known risk. In that vein I want to point out this is a test flight. In a sense, they're all test flights."
Here is the flight plan for Wednesday (acronyms: OBSS - orbiter boom sensor system; RMS - remote manipulator system, or robot arm; OMS POD - orbital maneuvering system rocket pod; SAFER - simplified aid for EVA resuce; a jet backpack):
REV...EVENT..........................MET in DD/HH:MM...EDT........GMT July 27 10...DISCOVERY CREW WAKE UP.................00/14:00...12:39 AM...04:39 12...WB-57 VIDEO REPLAY...............KSC...00/16:21...03:00 AM...07:00 12...RMS CHECKOUT...........................00/16:30...03:09 AM...07:09 12...FLIGHT DIRECTOR UPDATE...........JSC...00/16:51...03:30 AM...07:30 12...RMS GRAPPLE & UNBERTH OF OBSS..........00/17:15...03:54 AM...07:54 12...Ku BAND ANTENNA DEPLOYMENT.............00/17:30...04:09 AM...08:09 13...OMS POD PHOTOGRAPHY....................00/18:00...04:39 AM...08:39 13...RENDEZVOUS TOOLS CHECKOUT BEGINS.......00/18:40...05:19 AM...09:19 13...RMS/OBSS SURVEY........................00/18:45...05:24 AM...09:24 13...SAFER CHECKOUT.........................00/19:10...05:49 AM...09:49 15...AIRLOCK PREPARATION....................00/21:10...07:49 AM...11:49 15...EMU CHECKOUT...........................00/22:00...08:39 AM...12:39 15...ODS RING EXTENSION.....................00/22:15...08:54 AM...12:54 17...OBSS BERTH.............................01/00:10...10:49 AM...14:49 17...MISSION STATUS BRIEFING..........JSC...01/00:21...11:00 AM...15:00 17...RMS SURVEY OF DISCOVERY................01/00:55...11:34 AM...15:34 18...VTR PLAYBACK OF OBSS VIDEO.............01/02:30...01:09 PM...17:09 20...VIDEO FILE........................HQ...00/04:21...03:00 PM...19:00 20...DISCOVERY CREW SLEEP BEGINS............01/05:00...03:39 PM...19:39 20...FLIGHT DAY 2 HIGHLIGHTS..........JSC...01/05:21...04:00 PM...20:00 22...POST-MMT BRIEFING................JSC...01/07:21...06:00 PM...22:00 24...POST-MMT BRIEFING REPLAY.........JSC...01/11:21...10:00 PM...02:00
See the Status Center for full play-by-play coverage.