Review board says shuttle safe despite NASA failure to fully implement three CAIB recommendations

Review board says shuttle safe despite NASA failure to fully implement three
CAIB recommendations

http://cbsnews.cbs.com/network/news/space/current.html

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."
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 a formal flight readiness review later this week at
the Kennedy Space Center.

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 o 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 creatino 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 stuf 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."

--
--------------

Jacques :-)

www.spacepatches.info

Jacques van Oene wrote:
snip most of quote
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.

Are there going to be cameras to monitor this?

Ian Stirling wrote:
Jacques van Oene wrote:
snip most of quote
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.

Are there going to be cameras to monitor this?

Google for the upgrades to the camera systems; cameras have been
rehab'd (some for the first time in a long time, IIRC), and additional
cameras have been installed.

2 WX planes are to fly additional telescopes to increase the altitude
at the flight can be visually monitored.

The belly cam has been upgraded (or supplemented?) to digital for more
immediate analysis of imagery. I don't recall that the belly cam film
was recovered from Columbia.

Whether any of these cameras can spot a 0.5 oz chunk of foam is beyond
what I've picked up, though.

/dps

snidely wrote:


Ian Stirling wrote:
Jacques van Oene wrote:
snip most of quote
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.

Are there going to be cameras to monitor this?

snip
Whether any of these cameras can spot a 0.5 oz chunk of foam is beyond
what I've picked up, though.

Many thanks.