The Weekly Reflektion 40/2022

Risk assessments are a key part of ensuring that any activity or project can be carried out safely. Risk assessments can be major activities with multiple participants perhaps over several days. Risk assessments can also be short and sweet and consist of a quick review before the job gets done.

What are the factors that influence whether your risk assessments will achieve their objectives?

The culture in NASA was built on the German V1 and V2 rocket development. Technical rigour, structured approach, extensive quality control, learning and quick response to challenges. Forums for discussion could be deliberatelyadversarial and the language used was secondary to the key technical points that were made. Little room for the sensitive engineer and no room for the engineer that could not justify his/her views with hard and verified data. This culture was certainly a major factor in the development of the Saturn V rocket and the successful moon landing on 20th July 1969.

During the space shuttle program NASA completed an extensive risk assessment process before each launch. The Flight Readiness Review (FRR) consisted of four levels of assessment. Level four was a collaborative process with all the space shuttle contractors to ensure all issues related to the launch were properly prepared and verified including a review of relevant data. Level three was an adversarial process where the basis for the decision was challenged both by people in the organisations working on the shuttle and from independent persons (outside eyes). Level two was carried out at a higher management level and provided the technical oversight for the senior management. The Level two assessment included a Delta review where any major changes from the previousFRRs were reviewed in detail to ensure the change had been properly reviewed and potential consequences assessed. Level one was the senior management, and the assurance that the risk assessment process had been carried out thoroughly and in accordance with the FRR procedure. The FRR for 25thmission was completed, and the launch approved for Challenger in January 1986.

On the day before the scheduled launch the weather forecast was for cold conditions and a predicted temperature of -8 C. No launch had taken place at such a low temperature. NASAinitiated a review and requested all their contractors to assess their systems and equipment for the low temperature. Morten Thiokol was responsible for the solid rocket boosters (SRBs) and there had been several problems with the sealing of ‘O’ rings in the SRB joints on previous launches. Up until this moment the Thiokol engineers had resolved the uncertainties surrounding the ’O’ rings and convinced themselves that the risk to the shuttle was acceptable. Suddenly, with the new information, some of the engineers got cold feet. They started to doubt the integrity of the ‘O’ rings and advised to delay the launch. They provided data on ‘O’ ring leaks vs. ambient temperature on launch day to justify their recommendation.However, the data was hastily put together and not particularly convincing. NASA accepted the launch delay recommendation but questioned the engineers’ judgement based on the poor data presentation. The technical rigour culture kicked in and the Thiokol management requested a review of the data. They changed their recommendation to NASA and a decision to launch was made. Seven people died on 28th January 1986 when an ‘O’ ring leak on an SRB led to a shuttle break up and explosion.

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