Readdy addresses the media in the hours after Columbia's tragedy February 1. Photo: NASA

William Readdy, associate administrator for spaceflight and a former shuttle commander, told the Columbia Accident Investigation Board he did not consider asking for a spy satellite inspection of Columbia's left wing during the doomed ship's mission because the agency had already concluded the shuttle could land safely.

But in a letter to the CAIB, the Senate and House Intelligence committees and the NASA Inspector General, Readdy said he agreed that NASA could accept an offer from an unnamed government agency - presumably the National Imagery and Mapping Agency - to perform such an inspection on a "not-to-interfere basis."

But no such inspection was ever formally requested by NASA and no such remote inspection ever took place.

"If we had thought for a moment there was a problem, we would have asked," Readdy told reporters today in Washington.

During Columbia's launching Jan. 16, three pieces of debris broke away from the shuttle's external fuel tank about 81 seconds into flight. One piece, roughly the size of a suitcase, slammed into the underside leading edge area of the orbiter's left wing.

When the impact was discovered during routine post-launch analysis of ascent film and video, NASA managers ordered Boeing to carry out an analysis to determine what sort of damage such an impact might have caused. The Boeing team ultimately concluded the tank debris could have caused enough damage to the shuttle's fragile heat-shield tiles to produce localized, potentially severe damage. But the engineers concluded the potential damage did not pose a safety-of-flight concern and that Columbia could safely land.

NASA's mission management team, chaired by Linda Ham, a former ascent/entry flight director, accepted that analysis and the space agency never requested help from NIMA or other agencies operating the nation's most sophisticated imaging satellites and ground-based satellite-tracking telescopes.

That decision has been the subject of second-guessing and criticism in the wake of the disaster. In the days after the mishap, shuttle program manager Ronald Dittemore said no request for satellite imagery was made because the resolution of the imagery, based on past NASA experience, would not be high enough to reveal damage to individual tiles and because the Boeing analysis had concluded Columbia could land safely.

During Columbia's mission, however, Wayne Hale, a senior flight director now serving as launch integration manager at the Kennedy Space Center, made inquiries about the possibility of Air Force help inspecting Columbia. But those initial efforts were terminated by senior management.

"The SSP (space shuttle program) did not want any data and in fact there was never a formal MOD (mission operations directorate) request made from the FDOs (flight dynamics officers) or the Flight Director," Steve Stich, a flight director himself, wrote in an email to a colleague.

In a February interview, Hale declined comment on the matter, saying "I probably ought to wait until I tell the board my story. That's coming up."

Readdy's letter to the CAIB, reviewed by CBS News today, shows more senior managers also discussed the issue.

"A NASA individual visited me in my office," Readdy's letter to the CAIB begins. "That person and another individual from another agency had been discussing the external tank debris issue during STS-107 ascent. He wanted to discuss an 'offer of support' from the other agency with respect to observing the space shuttle Columbia on orbit. He explained that NASA would have to request that support on an emergency or high priority basis.

"I explained that the ET debris and possible implications to the left wing thermal protection system had been analyzed and reported to the Mission Management Team and documented in MER (mission evaluation report) daily report FD (flight day) 12 dated 1/28/03 1245 GMT.

"My understanding was that the space shuttle program was well aware of those capabilities that could be provided by the other agency and it had concluded that the offer would not contribute to the analysis. I related that as well as the conclusion reached by the MMT that there was no 'safety of flight' issue, and for those reasons there was no rationale for requesting emergency or high priority support.

"He reiterated that the other agency desired to support on a 'not-to- interfere' basis. I acknowledged this information, told him again that this was not viewed as a 'safety of flight' issue, but told him to accept the offer of support on a 'not-to-interfere' basis."

Ted Molczan, a respected satellite observer, has calculated that Columbia could have been imaged on multiple occasions by classified optical imaging satellites. Resolution would have varied from six to 16 centimeters, or 2.3 to about six inches.

"As of this writing, the precise cause of the Columbia accident is unknown, so it is impossible to know whether or not high-resolution imagery would have been useful," Molczan writes on a web page devoted to the topic. "There may not have been any outwardly visible signs. Even if there was something portentous to be seen, the outcome might have been the same. At this point in the investigation, having clear imagery of the left wing probably would be valuable, but that is easy to say in hindsight."

In other developments, Readdy sent a letter Wednesday to Michael Kostelnik, deputy associate administrator for the space shuttle and the international space station programs, asking him to "begin to identify those critical actions now that we believe need to be completed before a safe return to flight can be assumed. We will adjust this preliminary planning as necessary as we receive recommendations from the CAlB."

"The Deputy Associate Administrator for International Space Station and Space Shuttle Programs will establish a formal "Return to Flight" team, and provide direction for the team to address these actions and other actions determined necessary to comply with the formal recommendations of the CAIB," Readdy wrote.

The team "will plan for a safe return to flight as soon as practicable. As a goal, the SSP shall plan for corrective actions and reviews which support a launch opportunity as early as the Fall of 2003. The team will work closely with the leadership of the International Space Station (ISS) program to ensure that return to flight plans support an optimal return to the tasks of ISS assembly and continued logistics support."

Readdy said the team should consider:

• A thorough review of key shuttle systems, including the insulation currently used on the external tank;
• Development of in-flight tile inspection and repair kits;
• A review of radar and photographic coverage policies for launch and entry;
• A review of failure modes and effects analyses, critical items lists, waivers and hazards;
• Operational concepts for on-orbit inspection and repair of TPS;
• How in-flight safety issues are resolved, "including the appropriate level of management visibility and decision in that process."

"I am asking you to initiate these Return to Flight activities as soon as possible, establish this team, and provide a preliminary action plan no later than 1 April 2003," Readdy concluded. "You will be responsible for providing the team charter and day-to-day direction."

Readdy plans to establish and chair a Spaceflight Leadership Council to oversee return-to-flight activities. Michael Greenfield, associate deputy administrator for technical programs, will co-chair the panel.

"Much needs to be done as we move forward to fly again," Readdy concluded. "I anticipate that our processes will be strengthened and that the safety of flight enhanced as we return to flight."

Readers should keep in mind that setting this Fall as a goal for return to flight is little more than motivational talk at this point. Until the CAIB completes its report and NASA assesses what corrective actions might be necessary, talk of launch dates seems more than a bit premature.