Nasa managers could be hauled before Congress to answer claims that they ignored doctors’ advice and allowed space shuttle astronauts to fly while drunk.

The US space agency announced last night that it is to shake up the way it monitors crews in light of the allegations, revealed formally yesterday by a panel set up to review astronauts’ health and wellbeing.

“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 stated.

“Alcohol is freely used in crew quarters,” it explained. “Two specific instances were described where astronauts had been so intoxicated prior to flight that flight surgeons and/or fellow astronauts raised concerns. However, the individuals were still permitted to fly.”

Air Force Colonel Richard Bachmann, chairman of the investigating panel, said that the known drinking incidents involved personnel on the ground and in orbit. After drinking heavily, an astronaut flew on a Russian spacecraft, while another was cleared to fly on a space shuttle mission that was later aborted for mechanical reasons.

“It’s not unique to the shuttle, it’s not unique to the T38s [Nasa training jets], it’s not unique to the space station,” Colonel Bachmann said. “We have no way of knowing if these are the only two incidents that have occurred in the astronaut corps or whether they are just the tip of a very large iceberg.”

The scandal comes five months after Lisa Nowak, 44 — who went into orbit on board Discovery last year — was arrested for attempting to kidnap a love rival. The back-to-back episodes have left Nasa once again struggling for credibility.

“Instances were described where major crew medical or behavioural problems were identified to astronaut leadership and the medical advice was disregarded,” the report, based on interviews with 14 astronauts, reveals.

Professor Richard Berendzen, a former Nasa consultant, said last night: “If this is true, it’s beyond appalling and it’s not the glory days of the Nasa we once knew.”

The alleged offenders have not been named. Jeff Williams, who returned last year from a six-month stint on board the International Space Station, said: “Let’s face it, astronauts are a bunch of brothers and sisters and they’ll cover each other’s backsides . . . Who knows what the role of the particular ones was to be?”

The scandal will not help Nasa’s hopes of winning an increase in government funding. It is already fighting budget shortfalls, despite facing an increasing list of goals.

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