During the traditional on-orbit news conference held on Friday the crew of the Space Shuttle Endeavour
said it agrees with NASA decision not to repair damage the shuttle sustained during takeoff.

"We're certainly concerned that if we did the repair we could do more damage to the underside of the orbiter," Commander Scott Kelly said. "The shuttle crew and the staging crew agreed with the decision not to the repair."

"I think it was absolutely the appropriate decision to forgo the repair, and that they took the appropriate amount of time to come to the decision," he added.

Late Thursday NASA mission managers in Houston decided that Saturday’s spacewalk will not include repairs of Space Shuttle Endeavour’s heat shield.

"After hours of reviewing data and imagery collected during the inspections by the (shuttle) crew, the managers decided the damage did not pose a safety risk to the crew or Endeavour," a NASA statement said.

"The MMT made two significant decisions tonight," the chairman of the mission management team, John Shannon said. "The first was a unanimous recommendation that the damage we saw after reviewing all the engineering tests and analysis was not a threat to crew safety, this was not something that the astronauts are in danger about. We had thought that for several days, but we were waiting for the final analysis to be complete.”

The damage is not enough to risk a catastrophic failure of the shuttle's heat shield, like the one that destroyed the shuttle Columbia on re-entry in February 2002, but the process of underside repairs during a spacewalk would have entailed risks for the astronauts.

The crew was slated to begin their fourth and final spacewalk on Saturday and astronaut Dave Williams and space station flight engineer Clay Anderson are to conduct Saturday's spacewalk. During this spacewalk Willians and Anderson are to install and remove antennas on the outside of the ISS and conduct other construction projects. In other activities, the crew has been transferring cargo and and troubleshooting a problem with an internal communications system.

The cargo transfers have been ongoing since shortly after Endeavour arrived Aug. 10. STS-118 delivered supplies and equipment to the orbital outpost and will return unneeded station items and science experiments to Earth.

Under the current schedule on Monday, the shuttle is to undock from the International Space Station and head earthward, with landing at Florida's Kennedy Space Centre planned on Wednesday.

But according to the latest reports, NASA is worried about the effects of Hurricane Dean. The National Hurricane Center said early Saturday that hurricane Dean was developing into an "extremely dangerous" category four storm as it heads toward the Yucatan peninsula in Mexico.

Winds were gusting at 240 kilometres per hour, putting it at the upper range of category four, and meteorologists said in broadcast reports it could jump to category five as it picks up strength over the warm Gulf of Mexico waters.

That’s why NASA Mission control is taking in consideration to scale back Saturday's spacewalk to allow for a possibly early end to Endeavour's mission. NASA wants to keep its options open for moving up Wednesday's shuttle landing by one day, and shortening the spacewalk would be one way to do it, said Le Roy Cain, a ranking member of the mission management team, quoted by Associated Press.

Another, less likely option is to to keep the shuttle at the international space station longer than planned.