PPI SyEN Forum
PPI SyEN FORUM
Selected correspondence from readers, authors, and contributors
Selected correspondence from readers, authors, and contributors PPI SyEN FORUM offers the opportunity for feedback and discussion on topics around systems engineering – especially those that have been (or should be) addressed in PPI SyEN. Please send your email to PPISyEN@ppi-int.com
Defeating Complacency – Obstacle to Mission Success by Scott Jackson, PhD On the day after the successful SpaceX mission, I ran into an old friend. “How are you?” he asked. Knowing that he intended his question to be a common courtesy, I did not give him a courteous answer. “Depressed” I answered. “Why? He replied. “I am depressed about the failure of the SpaceX mission.” I said. “But” he replied, “the mission was a total success.” “I know,” I replied, “I am talking about the one around the corner. It has all the potential for failure.” As a part of my career in systems engineering, I have studied all the major system disasters, what caused them, how they can be prevented, and how can the system recover from a disruption. Obvious accidents include Columbia, Challenger, and Tenerife, the deadliest accident in aviation history. Systems that recovered include Apollo 11 and Apollo 13. Returning to the topic of failures, Leveson [1] tells us that the two most common causes of failure are optimism and complacency. Optimism is simply the belief that a goal can be achieved that is beyond the capability of the current system. Complacency is more complex. It is the inattention to safety and other safeguards of success. So how are these obstacles overcome and show us a path to success? That is difficult to say, and that is why I was depressed. It will be remembered that Columbia and Challenger were only 17 years apart. One would think that the lessons from the first disaster would make the second one virtually impossible. But that was not the case. What happened in between? Did complacency set in? Following the splash-down of SpaceX the airwaves were packed with self-congratulation. The mood was euphoria. The question that was asked many times was: What is the main obstacle to doing it again? The answer was always the same: cost. It was pointed out that a new propulsion system would bring the cost down. With all respect, I cannot agree that cost is the main obstacle. I vote for complacency. So, the real question is: how do you control complacency? There are no easy answers. One approach is to find a complacency metric, that is, a way to measure complacency and determine how close you are to having mission success. Without going into details, I can report that there are no clear complacency metrics. At least I have not found one. What you can do is assure that you are following all the standard safety design procedures, such as the use of redundancy. But even there you have to make sure your process is complete and thorough. You cannot do that if you are suffering from complacency. I don’t want to leave you with the message that success is not possible. It certainly is, but you cannot relax.
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