# Holographic Mixed Reality System for Air Traffic Control and Management
## 6 Flight Scenarios and User Tests
The usability test mainly encompassed the four areas i.e., the usefulness, ease of use, ease of learning and satisfaction. While designing the questionnaire, the ease of the usability of Hololens was also taken into account as shown in Table 2.  
The results of the conducted user test are as follows: \begin{table}
\begin{tabular}{c c} \hline \hline
**Category** & **Question** \\ \hline \multirow{7}{*}{Usefulness} & (1) It helps me to detect possible emergency situations earlier through 4D \\  & representation of navigational data \\  & (2) It reduces time to interpret through 4D representation of navigational data. \\  & (3) It is helpful for air traffic control workflow in low visibility conditions. \\  & (4) It is helpful in the decision making process in complex air traffic scenarios. \\  & (5) It helps me to understand air traffic’s navigational data. \\  & (6) It helps me to interpret complex air traffic scenarios. \\ \hline \multirow{7}{*}{Ease of Use} & (1) It is easy to access and interact with various information related to air traffic. \\  & (2) It is easy to interact with the system. \\ \cline{1-1}  & (3) It makes overall air traffic control workflow easier to perform. \\ \cline{1-1}  & (4) The organization of information on the system screen is clear. \\ \cline{1-1}  & (5) It requires the fewest steps possible to accomplish the data. \\ \cline{1-1}  & (6) It does not require additional effort to use the system. \\ \hline \multirow{2}{*}{Ease of Learning} & (1) It is easy to learn to use this system. \\ \cline{1-1}  & (2) I easily remember how to use it. \\ \cline{1-1}  & (3) It can be used well in real operating environment. \\ \hline \multirow{2}{*}{Satisfaction} & (1) Overall, I am satisfied with this system. \\ \cline{1-1}  & (2) I believe air traffic controller will use the system well in their work \\ \hline \multirow{3}{*}{Hololens Usability} & (1) Hololens is easy to use. \\ \cline{1-1}  & (2) I will become skillful quickly with Hololens. \\ \cline{1-1}  & (3) Hololens has an intuitive way of interacting. \\ \cline{1-1}  & (4) I feel comfortable using Hololens. \\ \cline{1-1}  & (5) Hololens is easy to learn to use it. \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Holographic mixed reality system questionnaire. As shown in Figure 10, the category of usefulness in the questionnaire, achieved higher scores than the remaining three categories. This is likely to be associated with the holographic device's view and usability, which is the ease of use. During the experiments, the subjects pointed to a narrow field of view, unfamiliar interactions, and so on. The subjects were unfamiliar with the Hololens device's gesture input method and found it difficult to learn. These limitations of the device may have affected the system usability results. The user test resulted in positive feedback about the applicability of the system along with constructive criticism to enhance the system. They also recorded their points of view about the hardware used. The overall feedback of each expert is as follows:  
<Participant 1>  
1. As a tower cab, it is a good way to monitor the work of the tower team. 2. The narrow field of view (FOV) of the Hololens makes it difficult to analyze a wider area which may result in difficulty to identify objects. 3. While the flight had been in progress, detailed information i.e., altitude, speed of aircraft etc. were shown along with aircraft. However, it was suggested to show the required information when it is needed. <Participant 2>  
1. It would be good to use it for simulation of flight operations as it enhanced the analysis power pretty well. 2. The narrow FOV of Hololens was a problem. Interaction was quite difficult and extensive training about how to use Hololens is required. The overall feedback from the experts can be seen as both positive and negative.