Monday, August 1 2005 11:40 Hrs (IST) - World Time -

Houston: NASA (National Aeronautics and Space Administration) engineers are determining whether two strips of heavy insulating cloth dangling from Discovery's underbelly could lead to overheating and endanger the shuttle's re-entry into Earth.

The agency may order the first space walk to the underside of the orbiter if engineers determine that the strips pose a serious problem.

Analysts are studying whether these strips of ceramic fibre cloth used to fill the gaps between thermal tiles could lead to unusual patterns of heating during re-entry.

"Engineers were concerned that there was a risk of them (the strips) upsetting the flow of air over the vehicle during re-entry and causing higher-than-usual temperatures to pummel the heat shield," Wayne Hale, deputy shuttle programme manager told reporters at a briefing yesterday (July 31, 2005).

The potential fixes could be folded into an August 3 space walk, the last of three planned space walks for Discovery's crew, or even warrant a fourth extravehicular activity (EVA), though mission managers stressed that option is remote at best and it is still undecided whether any action is required.

"We have a team of folks working aggressively on options to make that gap filler safe if we decide it's an issue," said Paul Hill, lead flight director for Discovery's STS-114 mission, adding that a separate team is studying the re-entry heating effects involved with leaving the protrusions in place.

"We expect to have final results on aero heating and a decision on whether we need to do anything about the gap fillers today (Aug 01, 2005)."