Flight Readiness Review "Intensive and Spirited"

After two days of "intensive and spirited" debate and deliberation, NASA's Flight Readiness Review (FRR) Board gave the green light for a July 1 launch of Space Shuttle Discovery. "There were many different viewpoints about whether we were ready to fly," said NASA Administrator Mike Griffin, "and we've decided that we are." The announcement came in a press conference Saturday.

Wayne Hale, Deputy Manager of the Space Shuttle Program, said there were at least 250 people involved in the discussions. "Contrary to prior FRRs, questions and concerns were accepted and addressed from all people," said Hale. "Dissent was welcome."

In the end, NASA's safety engineer and chief engineer recommended a "No Go" for launch until the foam surrounding the tank's 37 ice/frost ramps could be redesigned. The engineers are concerned that debris shed from the tank will damage the shuttle, as it did in the launch that ultimately ended in Columbia's tragic re-entry breakup in 2003.

True to what Griffin calls the agency's "new culture of openness and healthy debate," the dissenting engineers were allowed to type their concerns, in their own language, directly into the FRR Boards final report.

In a surprisingly frank and open dialog with the press, Griffin admitted the decision to fly was not unanimous. "You have to understand that NASA gets a lot of external advice, and I get a lot of advice internally. But, in the end, it's just advice. Somebody's got to make the decision and that's what you pay me for."

"Debris shed from the tank does not represent an ascent risk," Griffin said, "it represents a descent risk." He would have had to think harder about his "go" decision, he implied, if they did not have a safe haven in the space station, a back-up space shuttle ready to go for rescue, and, if necessary, assistance from Russia.

Despite Griffin's confidence in the mission, Hale said that the foam surrounding the ice/frost ramps is still at the top of NASA's "risk chart."

"I have launched a ‘tiger team' to develop a new design in rapid but thorough fashion," said Hale. "The risk is acceptable for a limited number of flights until a new design is available."

Griffin was less comfortable even calling it a risk. "I do not agree with categorizing [the risk of debris damage] as probable. Now, in fact, we have had 114 flights with this vehicle. And, while we've had two loss-of-vehicles incidents, they were not due to ice frost ramps. Can we fly a number of flights without a probable incident? I believe we can."

"This is a matter of programmatic risk," Griffin added, "not crew risk. The shuttle will be retired in 2010. We need to accept some programmatic risk and get on with it. That is not the same as accepting crew risk." If the risk doesn't pay off, Griffin assured, and NASA loses another shuttle vehicle, he will be the first to call for an immediate end to the shuttle program.

William Gerstenmaier, NASA's associate administrator for space operations, said the two-day FRR tackled lots of other issues besides the foam and ice/frost ramps. "We reviewed everything we could to make sure we were really ready to fly. Losses of ice/frost ramp foam are expected to be similar to past launches, which are acceptable losses for STS-121."

STS-121 and the next 15 consecutive missions are designed to complete the construction of the international space station prior to the scheduled phase out of the shuttle program in 2010.

Launch director Mike Leinbach said the processing of Discovery was going extremely well and there were no problems that might preclude a July 1 launch.

Preparations for Discovery's sister shuttle, Atlantis, were also proceeding on schedule in the event it would be needed for a rescue mission, according to NASA.

A rescue shuttle could be called up within 10 days of Discovery's launch, and be in the air 47 days after that. Leinbach said there would be a two-week window of launch opportunity at the end of August and first week of September, and that Atlantis would be ready for an August 21 launch if necessary. The Discovery crew will have enough supplies on board for 82 days.

Countdown begins Wednesday, June 28 for a scheduled 3:43 pm EDT launch from pad 39B at Kennedy Space Center.

FMI: www.nasa.gov