In aviation accidents, a chain of events (or error chain) is the many contributing factors typically lead to an accident, rather than one single event. These contributing actions typically stem from human factor-related mistakes and pilot error, rather than mechanical failure.
Sometimes you find interconnectivity in strangest places and several years ago I recall reading an article reviewing the US Space Shuttle Challenger Disaster which occurred on January 28, 1986 in which the Solid Rocket Booster malfunctioned upon launch and tragically resulted in a massive explosion killing all seven crew members on board over The Atlantic Ocean.
The piece struck a chord with me as I recall watching the event live on TV as a child. It was a surreal experience; seeing the explosion and hearing the seemingly endless silence that followed from the usually vocal new reporters. I guess some images stick with you forever.
The piece which is now sadly lost to memory was the first time I had read the term ‘Error Chain.’
‘In aviation accidents, a chain of events (or error chain) is the many contributing factors typically lead to an accident, rather than one single event. These contributing actions typically stem from human factor-related mistakes and pilot error, rather than mechanical failure.’
The term clearly stuck with me for some time as I recall bringing the term up while teaching Risk Management during an IDC a few years back and it has evolved in to a natural part of the presentation each time I give it. We watch a series of videos of a dramatized event that happened during confined training of a PADI Open Water Training dive in which a series of events also results in a tragic but easily avoidable accident in a pool.
After each section of the video the candidates are asked if they saw anything that concerned them and of they would have done anything differently. I recorded each one of their answers on the whiteboard and we go over each step once the videos have concluded to see if we can see the root cause for the accident or identify the first link of the error chain.
We invariably end up at the same place during every program which is great to see. The candidates identify that the instructor should have been present and in full control of proceedings before entering the water as defined by PADI standards of Direct Supervision.
‘Observe and evaluate student diver ability to perform skills and understand theoretical knowledge. Do not delegate this responsibility to certified assistants except as outlined in specific course standards or professional membership standards.’
-2017 PADI Instructor manual-
This is an awesome exercise to go through as one of the major objectives of professional diving programs is to instil an instructors mindset and chasing the error chain back to its root cause most certainly proves that they are ready to move forward in to teaching real candidates and use these critical thinking skills to avoid incident or accident happening in the first place.