CAPE CANAVERAL, Fla. -- Before resuming shuttle missions NASA must do a better job inspecting the leading edge of the spaceplanes' wings and ensure that the nation's spy satellites capture detailed images of the orbiter during each flight.
Those are the first two official preliminary recommendations from the Columbia Accident Investigation Board (CAIB), released Thursday in Houston.
In the past, CAIB chairman Harold Gehman has characterized these recommendations as "interim advisories" because they represent findings that definitely will be in their final report but can be released sooner to give NASA a chance to begin implementation.
Neither recommendation specifically reveals or offers insight into what caused the Feb. 1 loss of shuttle Columbia over Texas, but are nevertheless action items the space agency needs to address.
NASA Administrator Sean O'Keefe, speaking in Washington, D.C. at the National Press Club, embraced the recommendations and said one will offer a "technology challenge" and the other is essentially already a done deal.
And money to pay for these recommendations and the ones to follow, it seems, will be no object.
"Resources necessary to do this are going to be available and we'll assess whatever else is necessary as we go along," O'Keefe said.
The NASA chief added he anticipates a "significant increase" in the agency's budget during the next few years, not only to pay for the aftermath of Columbia but to move forward with an Orbital Space Plane and nuclear power initiatives that will set the stage for exploring Mars.
O'Keefe said NASA's budget is expected to grow from about $15 billion in the next year to almost $18 billion within the next few years.
Recommendation One
The board's first concern is with the reinforced carbon-carbon (RCC) panels that protect the front of the shuttle's wings from the hottest temperatures of re-entry.
There are 22 of the U-shaped, grey panels bolted to the front of each wing. T-shaped seals made of RCC material and other panels lined with black heat protection tiles protect the gap between the panels and the rest of the wing.
NASA considers the entire heat shield a "criticality one" item, meaning a failure of a panel would lead to the loss of the vehicle and crew.
According to the CAIB statement, the first recommendation was issued "because of the board's finding that current inspection techniques are not adequate to assess structural integrity of RCC, supporting structure, and attaching hardware."
Constructed in layers, the composite structure can often hide flaws. Visual inspections aren't enough to detect potential trouble inside, and it's impractical to break apart the RCC panels to check them after each flight.
The board wants NASA to explore non-destructive means of inspection, such as through x-rays or ultrasound, and to do so more frequently than the current maintenance instructions call for. "Visual external inspections and tactile checks are the only specified post flight inspections of RCC composite components," the statement said.
"The planned interval for removing RCC composite components for more thorough inspection is typically many flights, unless their removal is dictated by an observed visual surface condition or necessitated by the requirement to provide access for other operations."
It's possible that an RCC panel or T-seal was damaged by insulating foam that fell from the external tank and struck Columbia's left wing leading edge in a such a way as to create a breach in the heat shield that led to the tragedy.
O'Keefe said the new inspections offer a "technology challenge," but already has an experience engineer spearheading the effort to satisfy the board's recommendation.
Recommendation Two
The second recommendation intends to ensure that NASA always takes advantage of the nation's imaging capabilities -- namely from its classified spy satellites -- to help inspect areas of the shuttle's heat protection tiles that can't otherwise be seen by the crew in orbit.
"This recommendation was issued because of the board's finding that the full capabilities of the United States government to image the shuttle on orbit were not utilized," the CAIB statement said.
According to information released by the board and NASA, during Columbia's mission a NASA official in Florida informally requested the military take a look at the shuttle to see if cameras could pick up any damage to the heat protection tiles from the falling foam.
But that request was quickly "turned off" by other NASA officials, who at that point believed the Columbia crew was in no danger from any tile damage and didn't think the classified spacecraft would be able to see anything anyway.
NASA has a Memorandum of Agreement with the National Imagery and Mapping Agency (NIMA) to make on-orbit imaging of the shuttle available.
In the past that imagery was available only when requested, but the CAIB recommendation calls for making "imaging for each shuttle flight a standard requirement."
Anticipating the request, NASA modified their agreement with NIMA and announced the change two weeks ago.
"We made corrective action on that right away and we have an operative procedure now that will make imagery and national assets and national means available to us during any operational activity," O'Keefe said.
The full CAIB report is expected in June and additional preliminary recommendations are expected, board officials said.
NASA continues to plan for a return to flight before year's end.
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