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Board: Shuttle safe despite missing 3 recommendations
BY WILLIAM HARWOOD
STORY WRITTEN FOR CBS NEWS "SPACE PLACE" & USED WITH PERMISSION
Posted: June 27, 2005

WASHINGTON - An independent panel charged with assessing NASA's implementation of post-Columbia safety upgrades said in its final hearing today that the agency has failed to fully implement three of the most critical safety upgrades recommended by the Columbia Accident Investigation Board.

But that failure, while potentially embarrassing to NASA, is as much a matter of semantics and the wording of the recommendations - and a much improved understanding of the shuttle's susceptibility to debris impact damage - as it is any lack of effort on NASA's part, panel members said.

In fact, the chairman of the Return to Flight Task Group, who piloted the shuttle Discovery on the first post-Challenger mission in 1988, said he would be willing to ride Discovery again next month when NASA hopes to resume shuttle flights after a two-and-a-half-year hiatus.

"I would not have a concern about flying," he said.

Said board member Joe Cuzzupoli: "We feel it is a safe vehicle to fly, based on their inputs."

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NASA plans to hold a formal flight readiness review Wednesday and Thursday at the Kennedy Space Center to review mission preparations and to set an official launch date. The agency hopes to launch Discovery between July 13 and July 31 on a long-delayed service-and-supply mission to the international space station.

It will be the first manned American space flight since the shuttle Columbia was destroyed during re-entry Feb. 1, 2003, a disaster blamed on a chunk of foam debris that broke away from the ship's external fuel tank during launch. The foam blasted a hole in the leading edge of Columbia's left wing, triggering the ship's destruction in the fire of re-entry 16 days later.

The Columbia Accident Investigation Board made 29 recommendations for improving shuttle safety, including 15 that were to be implemented before launchings resumed.

In July 2003, former NASA Administrator Sean O'Keefe set up a panel of aerospace experts, former astronauts and academics to assess the agency's implementation of the 15 return-to-flight recommendations. O'Keefe said NASA would not question the recommendations, but would carry them out to the letter. Covey and former Apollo astronaut Tom Stafford headed up the Return to Flight Task Group.

The panel had hoped to present its final report a full month before the resumption of shuttle flights. But the report was held up pending NASA's completion of last-minute work to analyze the threat posed by ice shaking of the external tank during launch.

The results of that analysis were reviewed Friday and while engineers were unable to precisely characterize the threat posed by ice, senior managers agreed the risk was acceptable. They plan to make a formal "go" recommendation during the formal flight readiness review later this week.

The last-minute analyses were key elements in two of the three open items being considered by the Stafford-Covey panel. The CAIB recommendations in question called for NASA to:

  • Initiate an aggressive program to eliminate all External Tank Thermal Protection System debris-shedding at the source with particular emphasis on the region where the bipod struts attach to the External Tank.

  • Initiate a program designed to increase the Orbiter's ability to sustain minor debris damage by measures such as improved impact-resistant Reinforced Carbon-Carbon and acreage tiles. This program should determine the actual impact resistance of current materials and the effect of likely debris strikes.

In the wake of the Columbia accident, NASA eliminated the bipod insulation directly responsible for the fatal impact and implemented a variety of other changes to minimize foam shedding. The debris that doomed Columbia was as big as a suitcase and weighed 1.67 pounds. Engineers believe the largest piece of foam that might be shed during Discovery's launch is on the order of a half ounce.

Ice was a thornier issue to resolve and NASA managers still are not able to precisely characterize the actual risk. Estimates for the possibility of damage that would require a response range from 1-in-100 or so to one in several tens of thousands.

But the RTF task group today concluded NASA had not met the literal intent of the two recommendations.

The agency did not initiate a program to eliminate "all" debris from the external tank, a feat now thought to be impossible due to the basic design of the tank. And while NASA improved the strength of the shuttle's heat shield system in some areas, it decided to stop efforts to beef up the wing leading edge panels after a decision by the Bush administration to retire the shuttle by 2010.

The third open item centered on a requirement for NASA to develop credible repair techniques to fix heat-shield damage that might occur despite the other improvements:

  • For missions to the International Space Station, [NASA should] develop a practicable capability to inspect and effect emergency repairs to the widest possible range of damage to the Thermal Protection System, including both tile and Reinforced Carbon-Carbon, taking advantage of the additional capabilities available when near to or docked at the International Space Station.

Recommendation 6.4.1 also called for NASA to "accomplish an on-orbit Thermal Protection System inspection, using appropriate assets and capabilities, early in all missions. The ultimate objective should be a fully autonomous capability for all missions to address the possibility that an International Space Station mission fails to achieve the correct orbit, fails to dock successfully, or is damaged during or after undocking."

NASA has equipped Discovery with a 50-foot boom, laser sensors and TV cameras to carry out a detailed inspection of the shuttle on the second day of its mission. Additional inspections will be made by the space station's crew as Discovery approaches.

But NASA has been unable to develop certified repair techniques to fix entry critical damage to the shuttle's reinforced carbon carbon wing leading edge panels or its more fragile heat shield tiles. Repair techniques will be tested during Discovery's flight, but they are relatively immature and capable of repairing relatively minor damage.

NASA managers say agency and contractor engineers have done the best they could and that actual flight tests are required to find out how the techniques are affected by the space environment. Only then can they be certified and relied on for actual use in an emergency.

In the event Discovery suffers entry critical damage despite the other upgrades, NASA has made plans for the shuttle's crew to move into the international space station to await rescue by the shuttle Atlantis.

NASA managers believe the last-resort "safe haven" scenario, coupled with the redesigned tank, inspection procedures and other changes, make it reasonable to press ahead with launch.

The Return to Flight Task Group, after internal debate, adopted a rather strict interpretation of the recommendation in question, one that required any repair techniques to be thoroughly tested on the ground before launch to provide confidence they could be relied on in an emergency. And under that interpretation, NASA failed to meet the intent of the CAIB, the task group concluded.

But Adamson said the panel's interpretation was just that and that NASA had made strides in other areas that made up for any shortfall in the repair work.

"If you really get down to the heart of intent of CAIB, they were trying to break a chain of events," Adamson said. "What happened, a piece of debris gets liberated, it has the right transport mechanism, it impacts the orbiter in the right place, causes damage that needs to be repaired, there's no repair capability. And there's no ability to actually see and characterize the damage. All those things added up to conspire against Columbia.

"What the CAIB was really trying to tell us, I think, was that we've got to focus our effort in these four areas of reducing the debris, making the orbiter more impact resistant, be able to see and characterize the damage and then if you've got some, fix it," Adamson said.

"They wanted to see all NASA's efforts forcused in those four areas to reduce the likelihood that event could ever happen. And I think they've done that. That's exactly what they went off and did and the fact that in each one of these, taken independently, we might find some semantics in the wording that says we don't think they fully met the intent of this one (or that one) overall, they've significantly reduced the risk."

The actual "intent of the CAIB" has been a major question mark for NASA and the RTF Task Group because of the deliberately broad wording of recommendation 6.4.1.

For his part, Harold Gehman, the retired admiral who led the Columbia Accident Investigation Board, told CBS News in February that he was satisfied NASA had, in fact, met the CAIB's intent even though certified tile and leading edge repair techniques will not be available in time for Discovery's flight.

"It is our judgment that they're efforts have passed the criteria that we set up for them," Gehman said in a February interview.

Asked if he thought it was reasonable to fly without a certified repair technique given all the other improvements and safeguards implemented in the wake of the CAIB report, Gehman said: "That's correct."

"But that doesn't mean they're allowed to give up on the repair," he added. "In our view, they have to keep working at it."

The recommendations centered on four broad areas.

"First of all, you've got to understand foam creation and the creation of the hazard in the first place and you've got to do everything you can to prevent the creation of foam in the second place," Gehman said in the CBS interview. "The second thing you've got to do is, you've got to have much better pictures on launch and ascent to know whether or not there's been a foam event, or a debris event. You've got to know that. The third thing you've got to do is, you've got to essentially re-certify the orbiter to be ready to come back into the Earth's atmosphere. That translates into some kind of an inspection in orbit.

If serious damage is detected, "you have to have some minimal, practical kind of capability to do some kind or orbital repair, the best practicable kind of a repair. Knowing full well, depending on the size of the damage or what the nature of the damage was, there are some repairs that are beyond your capability to do in space.

"And it has been our unwritten policy ... and I told Stafford-Covey and asked Stafford and Covey to back me up on this and they have - and that is, you must attack all four of these things.

"Now you can do some better than others," Gehman said. "If you really think you've done a fabulous job of preventing the creation of debris in the first place, you've got some really good ways to take pictures to make sure your orbiter hasn't been struck or anything like that and you're really sure that it's in good condition, then you can do some of the other stuff to a lesser degree.

"But you do have to make an attempt at all four areas. Now, within those four areas, there are sometimes one, two, three or four things that you've got to do. But that was what our intent was."

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