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After the Challenger disaster occurred, the Rogers Commission investigating the accident reported that, in fact, "the decision to launch the Challenger was flawed". Since this time, the Challenger incident has become a classic example of what might be termed the human component in failure analysis. This component refers to the fact that as projects grow more and more complex, there is an increasingly greater chance of failure stemming from faults in project management and decision-making.

The Challenger explosion was technically caused by hot gases in an aft joint of the rocket, burning through two rubber seal rings called "O-rings". The specific failure occurred when the O-rings malfunctioned in the colder-than-usual temperatures on the day of the fatal launch. The key point, however, is that knowledge of potential problems with the O-rings can be dated as far back as 1977, almost ten years prior to the actual disaster. Clearly, undetected mechanical difficulties were not responsible for the disaster. The question is, of course, what was?


Communication Breakdown

In attempting to answer this question, the Rogers Commission uncovered numerous management - and organizational-related flaws in the project. For example, one of the major problems lay in communication within and between the three major organizations involved: NASA headquarters; the Marshall Space Centre; and Thiokol, the designer of the solid fuel rocket motor which housed the O-rings. On one hand, upper-level decision-making figures at NASA were not even aware of many of the concerns voiced by Thiokol engineers on the eve of the launch. These engineers, in turn, were not aware that the second of the two O-rings was no longer classified as redundant by the Marshall Space Centre. The engineers were unable to judge the acute seriousness of the problem nor were they able to impress the concerns they did have on those in charge.


Biased Judgement

Another project management-related problem brought to light by the Commission concerned biased judgement. In countless discussions prior to the launch, the O-ring issue was raised. The seriousness of the problem, however, was unclear. Psychologists contend that once a message is left open to interpretation, those in charge tend to insert a personal bent. What became clear was that decisions were not independent of political, financial, and even social pressures.

Other specific problems included inadequate problem tracking procedures, unclear specifications, and problems in establishing priority between safety and money.

There's a great deal of trade-off on design and a great deal of judgement involved in engineering and there always will be. The problem is everybody thinks of engineering as an exact science.

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