Shuttle Crew Knew About Damage

The commander of the space shuttle Columbia was informed about the foam strike most believe led to the ship's destruction in a casual e-mail from Mission Control a full week after liftoff. The e-mail dismissed any concern about the strike as "not even worth mentioning."

The wording of the e-mail gave commander Rick Husband and pilot William "Willie" McCool no reason to question the conclusion that Columbia was in no danger. And indeed, the commander replied in a light-hearted manner, reports CBS News Space Consultant Bill Harwood.

In a rare, documented acknowledgment from Columbia's crew on the subject of the foam impact, Commander Rick D. Husband cheerily replied: "Thanks a million!

"And thanks for the great work on your part AND for the great poems!" Husband e-mailed. "I saw the word Chine below and thought it was "China". I guess it's believeable [sic] that you might meet someone from China by the name of Main Wing :)."

The brief electronic exchange, disclosed Monday by the space agency, represents the latest evidence that astronauts were unaware of the impending danger when the stricken shuttle later made its fiery, violent return to Earth.

Flight director J.S. Stich conveyed his assurance to Columbia's commander and its pilot on Jan. 23, even as engineers elsewhere at the National Aeronautics and Space Administration continued to debate and study whether the foam impact might have fatally damaged protective materials on the shuttle's exterior.

Such materials included the gray-colored wing panels made from reinforced carbon, known within NASA as RCC, and insulating tiles covering other parts of the spacecraft.

"Experts have reviewed the high-speed photography and there is no concern for RCC or tile damage," Stich wrote to Husband and McCool. "We have seen the same phenomenon on several other flights and there is absolutely no concern for entry."

Stich described the foam strike as "not even worth mentioning" but said he was worried that reporters might ask the astronauts about it during in-flight interviews the crew conducted regularly.

As it turned out, no reporters ever asked about the foam strike.

Mission Control uplinked a video of the foam strike Jan. 25 and Husband replied the next day, saying only "thanks for the super work! We appreciate it."

Investigators are increasingly convinced that a 1.5-pound, suitcase-sized chunk of foam that peeled off the shuttle's external fuel tank and smashed against Columbia's left wing loosened a protective panel along the leading edge. That could have permitted searing temperatures to penetrate the spacecraft during its fiery return Feb. 1, melting key structures aboard Columbia until it tumbled out of control at nearly 13,000 miles per hour.

All seven astronauts died as the shuttle disintegrated over Texas during re-entry, just minutes short of a landing at the Kennedy Space Center.

In hindsight, the e-mails are disturbing because of the remarkably casual manner in which the foam strike, the worst in shuttle history, was dismissed, said Harwood. Other e-mails that were released after Columbia's Feb. 1 destruction showed mid-level engineers were concerned about potentially severe re-entry damage all the way until the day before landing.

NASA has said previously that Columbia's crew was apprised within days of liftoff about the foam investigation. But the crew members — and NASA's brass — were never told about the intense debate among some midlevel engineers over concerns Columbia's left wing might burn off and cause the deaths of the crew.

Previously disclosed notes from five high-level meetings during Columbia's mission showed that shuttle managers hardly mentioned the subject and dismissed it conclusively on Jan. 27 as "not a safety of flight concern."

NASA spokesman Kyle Herring said Stich's Jan. 23 e-mail assurance was not sent to Columbia's crew as a formal, operational dispatch and was based on ground assessments at the time. Herring said if NASA had concluded that Columbia's return would be risky, "then obviously more information would have been provided to the crew through channels other than a personal e-mail."

The foam strike was discovered during routine post-launch video analysis on Jan. 17. Mission managers promptly ordered an engineering assessment to determine whether or not Columbia's heat-shield tiles had been damaged enough to compromise safety during re-entry. An analysis carried out by Boeing concluded that while possibly severe heat damage to the underlying skin might require post-landing repairs, the impact did not pose a "safety of flight" issue.

The analysis indicated any impact on the reinforced carbon leading edge panels would do little more than mar the coating. As it turned out, the analysis was deeply flawed. The engineers extrapolated from an earlier tile-impact study involving much smaller pieces of debris and had virtually no data at all regarding how such strikes might affect RCC panels.

Post-accident analyses, impact tests using a nitrogen gas cannon, enhanced launch video and sensor data all indicated the 1.67-pound chunk of foam, which hit the leading edge at more than 500 mph, caused a breach that allowed super-heated air to burn its way inside during Columbia's re-entry Feb. 1. The wing ultimately failed and Columbia was destroyed.

But NASA's mission management team accepted the results of the Boeing analysis, quashed efforts to obtain spy satellite photography that might have resolved the issue one way or the other and informed the crew about the impact only in passing.

But according to a just-released transcript of internal mission control communications loops, the foam strike, or a debris impact of some sort, clearly was on the minds of re-entry flight controllers when the first signs of trouble developed.

NASA released printouts of the exchanges under the Freedom of Information Act and published them on its Web site.