spacetoday.net: Foam impact creates T-seal gap in test

Posted: Fri, May 30, 2003, 11:07 AM ET (1507 GMT)
STS-107 patch (NASA)

A chunk of foam fired at a segment of a space shuttle wing leading edge created a measurable gap in a T-seal, a finding that some have called a "potential breakthrough" in the Columbia investigation. According to a statement released late Thursday by the Columbia Accident Investigation Board (CAIB), investigators fired a 0.76-kg chunk of foam like that used on the shuttle's external tank at a segment of leading edge panels and seals taken from the shuttle Enterprise. The debris, striking the panels at 855 kmph, created a gap between one of the panels and a T-seal. The gap was 55 centimeters long and over 0.6 cm thick in some places. While the CAIB said it has not made any final conclusions about the Columbia accident, the research appears to bolster the current leading hypothesis that falling foam from the external tank damaged leading edge panels or seals, creating a gap that allowed hot plasma to enter the orbiter’s wing during reentry. Similar foam impact tests are planned for June.