The Challenger Tradgedy was Caused by an Apollo Mistake, Terminating Risk Analysis

NASA’s attitude toward risk changed drastically between the Apollo and Space Shuttle design. [1]Apollo engineers were seriously alarmed about riskbecause of the fatal Apollo 1 fire and the fact that the estimated probability of another fatal accident was extremely high. The predictions were so appalling thatmanagement terminated risk analysis to avoid public apprehension. Because risk analysis was not done, the Space Shuttle design accepted excessively high andunknown risk. The immediate cause of the Challengertragedy was the mistaken decision to launch in coldweather that impaired the O-ring seals, but the fundamental cause was the high risk of the shuttle design. Before Challenger, management asserted that the probability of a fatal accident was 1 in 100,000.Probabilistic Risk Analysis (PRA) found a roughly 1 in 100 chance of a shuttle failure.