[新闻] 美国宇航局的工程师们曾经在备忘录中警告航天飞机左翼可能会导致灾难性的后果。

WASHINGTON — Senior NASA engineers wrote in e-mails just one day before the Columbia disaster that the shuttle's left wing might burn off and cause the deaths of the crew, but they never sent their warnings to top NASA managers.

"Why are we talking about this on the day before landing and not the day after launch?" wrote William C. Anderson, an employee for the United Space Alliance LLC, a NASA contractor, less than 24 hours before the shuttle broke apart.

After intense debate -- occurring by phone and e-mails -- the engineers, supervisors and the head of the space agency's Langley research facility in Hampton, Va., decided against taking the matter to NASA brass, the Associated Press reported Wednesday.

Robert "Doc" Mirelson, NASA's news chief, took issue with the AP report stating that engineers' reports of Columbia problems were never sent to the "NASA brass."

Mirelson told Fox News that the worst-case scenarios written by engineers were taken to senior engineering management.

Mirelson said "these guys [engineers] get paid to come up with the worst-case scenarios" and that is what they did.

Jeffrey V. Kling, a flight controller at Johnson Space Center's mission control, foresaw with haunting accuracy what might happen to Columbia during its fiery descent if superheated air penetrated the wheel compartment.

Kling wrote just 23 hours before the disaster that his engineering team's recommendation in such an event "is going to be to set up for a bailout (assuming the wing doesn't burn off before we can get the crew out)." Kling the following day was among the first in mission control to report a sudden, unexplained loss of data from the shuttle's sensors in the left wing.

The e-mails released Wednesday describe a far broader discussion about the risks to Columbia than the concerns first raised three days earlier by Robert Daugherty, a NASA senior research engineer at Langley. He was mostly concerned about the safety of the shuttle landing with flat tires or wheels damaged from extreme heat.

Among the messages was one from Daugherty's boss at Langley, Mark J. Shuart, to another Langley supervisor, Doug Dwoyer, describing Daugherty as "the kind of conservative, thorough engineer that NASA needs."

"I can only hope the folks at (Johnson Space Center) are listening," Shuart wrote.

One e-mail, from R.K. "Kevin" McCluney, a shuttle mechanical engineer at Johnson Space Center, described the risks that could lead to "LOCV" -- NASA shorthand for the loss of the crew and vehicle. But McCluney ultimately recommended to do nothing unless there was a "wholesale loss of data" from sensors in the left wing, in which case controllers would need to decide between a risky landing and bailout attempt.

"Beats me what the breakpoint would be between the two decisions," McCluney wrote.

Investigators have reported such a wholesale loss of sensor readings in Columbia's left wing, but it occurred too late to do anything -- after the shuttle was already racing through Earth's upper atmosphere and moments before its breakup.

Many of the e-mails NASA released Wednesday were gathered at the direction of Ronald Dittemore, the shuttle's program manager at Johnson Space Center. In a message he wrote the day that news organizations first reported Daugherty's concerns, Dittemore asked for copies of the e-mails "so that I can see the traffic and get a feel for the conversations."

Daugherty's concerns -- and the following debate among other engineers -- took place days after engineers from the Boeing Co., another NASA contractor, had assured that Columbia could return safely despite possible damage to its left wing on liftoff from insulation peeling off its external fuel tank.

In response to Dittemore's request for the e-mails, Robert C. Doremus, a NASA employee at Johnson, on Feb. 11 summarized the earlier exchanges and concluded that Daugherty and three other engineers, on the afternoon before the breakup, agreed "we were doing a 'what-if' discussion and that we all expected a safe entry."

The e-mails also disclose that Dwoyer, a middle manager at Langley, wrote to the director of the research center, Del Freeman, and asked whether Freeman should contact William F. Readdy, NASA's associate administrator for space flight.

NASA officials said Wednesday that Freeman never contacted Readdy, and that Freeman considered the matter resolved after he discussed the problem with Langley engineers.

该电子邮件：

http://www.nasa.gov/columbia/COL_email_030226.pdf

The Associated Press contributed to this report.

下图是事故调查组一成员在肯尼迪宇航中心的机库里检查航天飞机残骸。