Engineers Had ‘Grave’ Concerns on Columbia

NASA engineers harbored a broader and deeper concern than previously disclosed about potential damage to the shuttle Columbia, according to hundreds of pages of e-mails and internal reports released Monday.

The chief engineer for the space shuttle complained during Columbia’s mission that the agency was wrong and that its judgment bordered on irresponsibility when NASA failed to ask for photographs from spy satellites to assess possible damage, according to one of the memos.

Rodney Rocha said that the damage to Columbia’s thermal protection system -- caused by foam debris that was observed falling from the external tank during launch -- “could present potentially grave hazards” and that heating could occur in the “most critical locations” inside the orbiter’s left wing.

Rocha wrote the memo as a draft e-mail on Jan. 22, 10 days before Columbia broke up on reentry, and addressed it to more than a dozen NASA officials all over the country, but he never sent it. Instead, he submitted a printout to a supervisor at Johnson Space Center, according to NASA spokesman Allard Beutel. Rocha apparently backed off from a wider distribution because of the tone, Beutel said.

Not long after the accident on Feb. 1, NASA officials said that they were aware of the foam strike, but that it did not amount to a safety issue and could not possibly have caused the accident. A report by the Boeing Co. that had been requested by NASA after the launch predicted a safe return for Columbia. But those early statements by NASA officials did not fully represent the serious concerns and the lack of consensus.

After videos of the foam strike were seen by engineers at NASA and at Boeing, a number of them quickly raised concerns, the e-mails show.

“There’s a lot of speculation as to the extent of the damage, and we could get a burn through into the wheel well upon entry,” wrote Carlisle Campbell, an engineer at Johnson Space Center.

“That’s amazing footage,” wrote Thomas Hoffman of Boeing. “I hope the tiles are OK (like I’m the only one concerned?)”

“This is, certainly, the largest one [foam piece] I have seen hit the orbiter,” wrote Carlos Ortiz-Longo of Johnson.

Toward the end of the mission, Robert H. Daugherty of the Langley Research Center in Virginia wrote, “Any more activity on the tile damage or are people just relegated to crossing their fingers and hoping for the best?”

The e-mails also show that NASA’s space shuttle safety chief, Bryan O’Conner, reportedly chastised officials at Alabama’s Marshall Space Flight Center in December after they defended the foam insulation on the external tank in a review. The briefing asserted that the external tank was “safe,” but O’Conner asked for a new hazard assessment. It is unclear what became of that request.

The documents also indicate for the first time that Columbia exceeded its planned reentry weight by about 700 pounds, causing officials to consider how that might affect the temperature during reentry. A heavier shuttle would encounter more heating because of additional friction with the atmosphere. Rocha, among others, explored how different reentry flight profiles would affect the heating, in which the shuttle faces skin temperatures of as much as 3,000 degrees Fahrenheit.

Since the accident, some experts have speculated on whether NASA could have done anything to save Columbia if it had known that the orbiter’s thermal protection system had been damaged. Those measures could have included cooling down Columbia’s underbelly before reentry by turning it away from the sun, flying as directly as possible to the ground by minimizing the cross range of the flight and jettisoning as much weight from the craft as possible before reentry.

But NASA officials did not take any measures. It considered but decided against asking the National Imagery and Mapping Agency, the intelligence shop that controls spy satellites, to get high-resolution photos of the orbiter. The Rocha memo lays out a precise and clear reason why NASA should not have hesitated to obtain the photos:

“The engineering team will admit it might not achieve definitive high confidence answers even with additional images, but without action to request help [to] clarify the damage visually, we will guarantee it will not.”

NASA Administrator Sean O’Keefe said last week that the space agency had reached an agreement with the mapping agency to routinely obtain photographs of the space shuttle during missions. However, future shuttle missions may also be limited to flights to the international space station, where astronauts would be able to make detailed observations and possibly repair damage.

The massive document released Monday afternoon did not include any e-mails or memos written by or addressed to senior NASA officials, such as shuttle director Ron Dittemore; William F. Readdy, the associate administrator for spaceflight; and his deputy, Michael C. Kostelnik. They were all aware during the mission about the damage assessments, but it is unclear what written materials they were provided and whether they become involved in any of the management decisions.

Meanwhile, a data recorder recovered in Texas shows that the temperatures inside Columbia’s left wing were surging three minutes earlier -- and by hundreds of degrees higher -- than previously known. Harold W. Gehman Jr., chairman of the Columbia Accident Investigation Board, said Monday that investigators hope to recover far more information from the recorder when it is fully analyzed.

The data gleaned so far from the recorder continue to emphasize the theory that the leading edge of the orbiter’s left wing was damaged by the foam debris during liftoff, Gehman said.

“We are still pulling all the data together to attempt to indicate where the breach is,” Gehman said. “But this certainly leads us away from things like tile and landing gear doors and things like that. It kind of leads us toward the leading edge.”

The first sign of unusual heating occurred just five minutes after the shuttle encountered the Earth’s atmosphere somewhere over the Pacific. A sensor behind a leading edge panel shot up to 450 degrees and then went dead.