“Newly disclosed e-mail inside NASA showed senior engineers worried a day before the Columbia disaster that the shuttle’s left wing might burn off and cause the deaths of the crew, a scenario remarkably similar to the one investigators believe actually occurred…. After intense debate — occurring by phone and e-mail — the engineers, some supervisors and the head of the space agency’s Langley research facility in Hampton, Va., decided against taking the matter to top NASA managers…” –NASA’s Worst Fears Realized AP/Wired)
Engineers worry all the time, about all sorts of things. Before the Challenger disaster in the 80s, most of those worries, and the dismissals of them, were oral, presented via teleconferences. Diane Vaughan’s The Challenger Disaster suggests that some engineers who worried the most weren’t able to get their concerns through the administrative layers, to the people who could take action.