Safety is the highest priority for Air Traffic Control. Attention is continually given to improving safety. The focus is on learning from the incidents that occur in practice and on preventing them happening again.
Our goal is to improve safety in the long term. Therefore, it is important to continually monitor the general trend in safety of our operation. This monitoring pays special attention to the significant incidents. These are incidents that pose a risk to the safe handling of aircraft and/or ground vehicles that can be in the vicinity of each other. Here it is not important which organisations or individuals played a role in the incident.
Significant incidents fall within the ICAO severity classification system, 'serious' and 'major'.
The figure below provides insight into the trend in the number of significant safety incidents in the LVNL operation from 2014 to 2018.
Every point on the trend line indicates the average number of significant incidents per 10,000 handled flights over the past twelve months, this is called the twelve-month average. This average is used to avoid transitory seasonal influences. Normalisation to the number of flights reduces the fluctuations resulting from changes in traffic volume.
Because, by definition, significant incidents occur infrequently, it is always possible for there to be an occasional rise or fall in a specific period. In such situations, an investigation must determine whether the trend provides a realistic picture of the safety situation.