In response, NASA said it launched an investigation to try to verify the allegations, embraced an astronaut code of conduct and was weighing changes in its drinking policies.
NASA convened the eight-member panel to examine its health policies after the arrest of astronaut Lisa Nowak in February on allegations she stalked and attacked a rival for the affections of a fellow astronaut.
"Interviews with both flight surgeons and astronauts identified some episodes of heavy use of alcohol by astronauts in the immediate preflight period, which has led to flight safety concerns," the report said.
The panel did not say when the incidents took place or name the astronauts involved.
"We don't have enough data to call it alcohol abuse," said U.S. Air Force Col. Richard Bachmann, panel chairman and commander of the Air Force School of Aerospace Medicine, who offered few details of the two incidents cited in the report.
"We have no way of knowing if these are the only two incidents that have ever occurred in the history of the astronaut corps or if they are the tip of a very large iceberg," Bachmann said during a 90-minute news conference.
Today's NASA astronauts do not generally convey the rip-roaring image of "Top Gun" fighter jet test pilots, but of quiet-mannered aeronautical engineers and scientists.
The report's release came a day after NASA said it was investigating sabotage of a noncritical computer due to be flown next month to the International Space Station on the space shuttle Endeavour. Despite that incident and the embarrassment surrounding Nowak's arrest, the U.S. space agency is moving forward as planned with its main task, the construction of the $100 billion space station.
'NOT GOING TO BE TOLERATED'
Bachmann said that of the two incidents in which NASA astronauts were cleared to fly despite indications they were drunk, one involved a space shuttle flight that ended up being postponed for other reasons and the other involved a Russian Soyuz spacecraft going to the International Space Station.
The report, one of two submitted to NASA chief Michael Griffin, said the U.S. space agency must fix "ingrained and long-standing" cultural and structural problems that may contribute to behavioral problems by astronauts.
"Alcohol is freely used in crew quarters. Two specific instances were described where astronauts had been so intoxicated prior to flight that flight surgeons and/or fellow astronauts raised concerns to local on-scene leadership regarding flight safety," the report added.
"However, the individuals were still permitted to fly."
NASA officials said they were unaware of any incidents in which astronauts were intoxicated prior to flight.
Shana Dale, NASA deputy administrator, said the panel did not provide specifics on the two incidents to NASA. She said NASA would conduct its own investigation to try to confirm whether the incidents occurred and the scope of the problem.
"Alcohol use in regard to spacecraft or aircraft -- and anybody's that's impaired -- is not going to be tolerated by this agency," Dale said.
Officials said NASA would make more explicit its policy that astronauts are barred from drinking 12 hours before a flight and must not be "under the influence nor the effects of alcohol at the time of launch." Dale said NASA would consider making the prohibition longer than 12 hours before launch.
The 12-hour rule previously was stated explicitly only in regard to flying T-38 training jets, not space flights.
Dale said NASA had accepted a series of recommendations made by the panel, including drafting some sort of code of conduct detailing acceptable behavior. Officials said it was premature to say an astronaut would be fired for violating it.
NASA also will make psychological assessments part of an astronaut's annual physical exam and take steps to make sure flight surgeons, fellow astronauts and others who may suspect an astronaut is drunk can better raise the concern, Dale said.
Güncelleme Tarihi: 28 Temmuz 2007, 10:43