NASA puts off shuttle space walk decision until Thursday
NASA postponed by one day a decision on sending astronauts at the International Space Station on a spacewalk to repair damaged heat tiles on the Endeavour shuttle before it returns to Earth, the agency said late Wednesday.
Endeavour mission chief John Shannon said that initial assessments show that damage to the shuttle`s structure did not appear to be severe, and that he was hopeful that there would not be a need for repairs.
"Yes, I will repeat it ... I am cautiously optimistic the repair won`t be needed," he told reporters.
On Tuesday NASA had said that a decision would be made by Wednesday evening on how to deal with the 8.75 by 5.0 centimeter (3.5 by 2.0 inch) gouge in Endeavour`s heat shield near a landing gear hatch, which likely was caused by foam shedding from the shuttle`s external fuel tank during launch.
The concern is that the gash could create excess friction as the shuttle hurtles into the Earth`s atmosphere at high speeds, though NASA has said the problem "poses no threat to crew safety or mission operations."
"The analysis we have shows that it will be no damage at all to the underlying structure, which was very good news to us," Shannon said Wednesday.
"I think most of the data are in place to make a decision but I want the team to go off and think about it over night," he said of the final decision.
He said that undertaking a fourth space walk on the current mission carried more risk than undertaking a repair not deemed absolutely necessary.
NASA officials earlier said the gouge was likely caused by a 100 gram (3.5 ounce) piece of foam, or foam with ice, that broke from the external fuel tank 58 seconds into the shuttle`s launch on August 8. Earlier reports characterized the debris as just ice.
The damage to the heat shield has evoked the February 2003 Columbia disaster, when broken tiles on the shuttle`s heat shield led to its disintegration upon its return from space, killing the seven astronauts aboard and putting in limbo the shuttle program for nearly 18 months.
|
