THE RESEARCH ON THE INFLUENCE OF WORKLOAD ON THE OCCURRENCE OF DIFFERENT TYPES OF ATC ERRORS

1. THE RESEARCH ON THE INFLUENCE OF WORKLOAD ON THE OCCURRENCE OF DIFFERENT TYPES OF ATC ERRORS Samartseva Elena IAN-519

2. Aims of the research provision • to investigate the reasons of high workload • to define the factors that influence the increase of workload the most • to define the quantitative characteristics of the main reason that cause sharp increase of workload and activity breakdown • to define types of errors that can occur due to high workload conditions

3. The research procedure • The research was performed by conducting a survey among the group of air traffic controllers – interns and ATC students. • During the survey there were 20 people interviewed and the results were represented in the form of statistics on each of the steps of the research. • The point of the research was to gather information regarding the work of an air traffic controller and workload that he/she might experience during his work, to provide the obtained results and to make the conclusions about the errors occurrence caused by high workload in air traffic control.

4. The 1st step of the research • During the 1st step of the research the participants were provided with a list of the most widespread factors that can cause high workload conditions during the shift. • Participants were asked to prioritize all of the reasons from the list putting the figures from 1 to 10 according to the importance of the influence of each reason on the workload (1 – the highest priority, 10 – the lowest one). • Participants were also encouraged to make comments and add their own reasons if necessary.

5. 1st step results

6. The 2d step of the research • During the 2d step of the research the participants were provided with an empty graph where they had to draw the line of dependence between number of ACFT in their zone and workload. They were also informed that the highest border of the graph must be considered as the highest workload – the one at which activity breakdown occurs. • The second task of this step was to point two numbers: - The number of ACFT in a zone at which, on their opinion, the conditions of high workload appear. - The number of ACFT in a zone at which the activity breakdown can occurs. • The last task was to depict these two numbers on the graph as a square and a circle correspondingly

7. 2d step results

8. Average result of dependence of workload on number of ACFT being simultaneously under control

9. The 3d step of the research • The last task was to identify which errors are most probable to occur during high workload conditions. • The participants had to tick off those errors from the list, sorted to the categories, which, on their opinion, could be caused by high workload. • Participants left empty those errors in the list, which can’t or are very improbable to occur due to exactly this conditions.

10. Equipment handling errors Radar usage: • selecting an inappropriate radar source; • selecting an inappropriate range (scale); • selecting the incorrect mode (SSR on/off, mode C on/off). Automation: • making incorrect inputs to the automated system. Radio/intercom: • selecting incorrect frequency; • selecting an incorrect button/address on the intercom; • transmitting while another transmission is in progress. Flight progress strips: • incorrect placement of strips on flight progress board; • strips placed in incorrect stripholders (colour coding); • strips not passed to correct controller.

11. Procedural errors: Handover at working position: • omitted/incorrect items; • rushed handover; • leaving the position before new controller is ready to take over. Documentation: • wrong approach/departure charts used; • briefing material not read. Checklists: • items missed; • checklist not used or used at the wrong time. Information: • approach/departure procedure information not provided or not provided in a timely manner to pilots; • weather/ATIS information not provided or not provided in a timely manner to pilots; • status of navigation aids information not provided or not provided in a timely manner to pilots. Separation minimums: • wrong separation minimum applied (i.e. wake turbulence separation).

12. Communication errors ATC to pilots: • missed calls; • misinterpretations of requests; • incorrect hearback; • wrong clearance, taxiway, gate or runway communicated. Controller to controller: • miscommunication or misinterpretation within the unit; • miscommunication or misinterpretation during coordination with an external partner.

13. 3d step results

15. Conclusions • Having the research provided we found out such facts: • The main reason considered to influence the workload increase the most is high density of flights • We have investigated the edge values of the aircraft in a zone for our group of future air traffic controllers Main errors that occur due to high workload have been found as well as we defined that the most frequently occurred categories of errors are automation errors (such as input of wrong data into the system) and communication errors (exactly missed calls) • According to the received information measures can be taken to prevent controllers overload, such as preventing the excess of number of ACFT in a zone, increasing controllers’ attentiveness to the most frequent errors, using different methods for eliminating of the reasons of errors occurrence.