> During inspections and analysis, however, investigators noticed some unanticipated variations across Orion’s heat shield. “Some of the charred material ablate

> During inspections and analysis, however, investigators noticed some unanticipated variations across Orion’s heat shield. “Some of the charred material ablated away differently than what our computer models and what our ground testing predicted,” Hu said. “More of this charred material was liberated during reentry than we had expected.” Yeah, the first thing I thought of when reading this was NASA/O-Rings and early indicators: > In a flight readiness review of March 1984, NASA's top managers discussed and accepted the idea that some O-ring erosion was 'acceptable' because the rings embodied a safety factor. The incidence of heat damage at the SRB joints was growing -- three of the five 1984 flights showed heat damage, eight of the nine 1985 flights, and the flight on January 12, 1986, just two weeks before Challenger. http://choo.fis.utoronto.ca/mgt/DM.case.html http://choo.fis.utoronto.ca/mgt/DM.case.html