## 5 Further Analyses and Discussion: Towards the Unwanted Chain of Errors Avoidance
\begin{table}
\begin{tabular}{c c c c c c c c c c} \hline \hline
**Year** & **2014** & **2015** & **2016** & **2017** & **2018** & **2014** & **2015** & **2016** & **2017** & **2018** \\ \hline Yes & 8 & 14 & 13 & 4 & 4 & 1 & 0 & 1 & 0 & 2 \\ No & 19 & 19 & 8 & 4 & 4 & 1 & 1 & 0 & 0 & 2 \\ No answer & 1 & 0 & 2 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ \hline
**Rank** & \multicolumn{6}{c}{**Master**} & \multicolumn{6}{c}{**Staff Captain**} \\ \hline
**Year** & **2014** & **2015** & **2016** & **2017** & **2018** & **2014** & **2015** & **2016** & **2017** & **2018** \\ \hline Yes & 19 & 8 & 5 & 0 & 9 & 0 & 0 & 0 & 0 & 1 \\ No & 8 & 13 & 8 & 3 & 1 & 0 & 2 & 0 & 0 & 1 \\ No answer & 0 & 0 & 3 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ \hline
**Rank** & \multicolumn{6}{c}{**Chief Officer**} & \multicolumn{6}{c}{**Staffey Officer**} \\ \hline
**Year** & **2014** & **2015** & **2016** & **2017** & **2018** & **2014** & **2015** & **2016** & **2017** & **2018** \\ \hline Yes & 17 & 10 & 5 & 5 & 7 & 4 & 1 & 0 & 0 & 3 \\ No & 9 & 7 & 2 & 0 & 4 & 0 & 2 & 0 & 0 & 0 \\ No answer & 0 & 0 & 0 & 0 & 1 & 1 & 1 & 0 & 1 & 0 \\ \hline
**Rank** & \multicolumn{6}{c}{**Second Officer**} & \multicolumn{6}{c}{**Third Officer**} \\ \hline \hline \end{tabular} Source: Authors.  
\end{table} 
Table 1: ECDIS EHO participants’ opinions regarding PNC removal divided by years and rank. Figure 10: HMI survey participants’ opinions regarding PNC removal (Q2: Do you think that it is still necessary to keep navigational paper charts after implementation of the mandatory ECDIS system?). Source: Authors. Masters and staff captains have favoured the PNC removal for an additional 10%, while there has been approximately 20% of the increase of the second officers who share the same opinions (in 2018, as derived from both surveys). There has also been a 4% decrease in opinions of the chief officers (from 90% to 86%), and 38% of the third officers who have favoured the PNC removal after the mandatory system implementation. The total share of the answers from participants who have supported the PNC removal decreased from 100% to 62%. Since the individual results have not been totally uniform, more specific research should be conducted, providing a larger, and therefore, more representative samples of participants' categories. So far and it is, generally speaking, logical, the senior ranks have been mostly more reluctant to discontinuation of the PNCs usage, as opposed to junior officers. The latter have been in total consensus about the PNCs' complete removal from the service. Another consequential and perhaps underrated question has emerged or, rather to say, it has been confirmed: To what extent will the traditional supporters ignore the usage and the features of the system as a result of their standpoints regarding the non-acceptance, or even resistance to the means? Although seemingly negligible, this issue refers to the desired synergy between traditional and system supporters, i.e., their ability for joint and successful achievement of safe navigation. Several potential issues and uncertainties can be identified on the basis of these results. The categorized issues have been shown in Figure 11. In their nature, they can be divided in two major groups: (i) system and data problems (grey coloured rectangles and orange arrows) and (ii) operational (navigator's) issues (blue coloured rectangles and orange arrows). Both can individually lead to potential precarious and difficult situations (red coloured rectangle), e.g., overreliance as a navigator's problem, or the ENC information quality as a data problem leading to difficulties or risks in system handling and the execution of navigation tasks. A combination of (i) (grey coloured arrows) and (ii) (blue coloured arrows) has been pointed out (red arrowed colour) as a most unwanted scenario, i.e., an operator with a low level of knowledge experiencing a system problem. As for discrepancies in the system acceptance, they could lead to intentional non-usage of the system and its features, nevertheless its role.