Investigators now believe that the debris started a chain of events
that led to Columbia's disintegration above Texas Feb. 1. All seven
Other records released Monday reveal the flight controllers' alarm
in the minutes before the disaster.
On Thursday, Jan. 23, flight director Steve Stich sent a personal
e-mail to Columbia's commander, Rick
Husband, and pilot, William McCool.
Stich's e-mail said he wanted to notify the crew that a piece of
foam had fallen off the external fuel tank during launch Jan. 16
and hit the shuttle's left wing.
The event, Stich said in the e-mail, ''is not even worth mentioning''
except that there was a news conference with the crew in a few days.
He told Husband and McCool that he wanted ''to make sure that you
are not surprised by it in a question from a reporter.'' The e-mail
said, ''Experts have reviewed the high speed photography, and there
is no concern for RCC or tile damage. . . . there is absolutely
no concern for entry.''
Reinforced carbon-carbon, or RCC, is the heat-resistant material
on the front edge of the shuttle's wing. Heat-protective tiles cover
the rest of the wing.
The expert review to which Stich referred was a preliminary analysis
by engineers from NASA and Boeing, a NASA contractor. The final
analysis, completed three days after Stich's e-mail, also concluded
that the foam strike was not a safety hazard.
Husband responded several days later. His e-mail began, ''Thanks
a million Steve!'' It closed with a ''happy face'' made of a colon
and a parenthesis.
Former shuttle commander Carl Meade said it's not unusual
for a shuttle crew to hear so little from the ground about some
problems. ''You've got to remember, on every flight, there are several
of these things that turn up, that turn out to be nothing. Of course,
in hindsight, that's not the right thing to do.''
As Columbia started its return to Earth, flight controllers at
Johnson Space Center in Houston chatted and joked as they monitored
the shuttle's progress, according to a newly released transcript.
A few minutes later, a mechanical-systems operator reported that
no data were coming from some of Columbia's sensors.
''What in the world?'' the operator said.
''This is not funny,'' said Jeffrey Kling, the head of the mechanical-systems
Kling and the operator puzzled over what happened. Then more measurements
''I am not believing this,'' Kling said.
''No . . . '' the operator said.
Columbia disintegrated shortly thereafter.