Increased Safety Goes Hand in Hand with Higher Cost Efficiency: Single-Controller Operation Showcasing Its Advantages

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The author presented a paper titled: Increased Safety Goes Hand in Hand with Higher Cost Efficiency: Single Controller Operation Showcasing its Advantage. However there are some observation and suggestions:

1. The author should expand the methodology

2. The results and discussion needs to be expanded

3. A comparison Table to see the difference between the authors methodology and the one presented in the literature is required

4. What is the novelty of the work?

Author Response

Note: We uploaded the revised zip and pdf and additional through Supplementary Files a pdf with coloured changes: red text shows deleted text, blue text show new text.

Comment 1: The author should expand the methodology 

Response 1: Thank you for taking the time to review our work. Could you be more specific about what aspects of the methodology you think are lacking? What specific changes or additions do you think would strengthen the study? We take all comments from reviewers seriously, including yours, and have made efforts to address similar concerns raised by other reviewers. However, we value constructive feedback and would like to understand your perspective in greater detail.

Comment 2: The results and discussion needs to be expanded 

Response 2: Could you provide more specific guidance on what aspects of the research or analysis you feel need further elaboration? That being said, we value the input from all reviewers and have taken into account the suggestions from other reviewers in results and discussion sections.

Comment 3: A comparison Table to see the difference between the authors methodology and the one presented in the literature is required 

Response 3: We have taken your comments into consideration and have included a summarizing table (Table 6) that provides an overview of the key methodologies employed by other publications in this field.

Comment 4: What is the novelty of the work? 

Response 4: The structure of the paper was detailed in the introduction section. The unique contribution of the paper to the research topic is highlighted following the research questions.

Reviewer 2 Report

Comments and Suggestions for Authors

The paper is related to the situation when air-traffic increases and in such scenarios air navigation authorities always face a staff shortage thus, this paper proposes a deployment of one controller per sector which could be a solution to staff shortage problems. However, there are following major concerns as mentioned below:

1. The title is too philosophical please propose a title that shares the insights of a paper to some extend. 

2. Within abstract author mentioned the staff shortage issue in a generic way, I mean there are number of other techniques to address the same issue so why someone will give importance to your suggested approach. Lack of novelty please improve abstract. 

3. Within the literature I suggest to summarise all such approaches addressing the staff shortage issue and or researchers who earlier introduced single controller along with their limitations and try to sync your arguments why you are proposing this and how it is different from previous approaches. 

4. In paper many of the sections and subsections are written in postulates form which is wrong approach to share your information in any technical form of writing. It is technical paper not a presentation please amend it. 

5. Add exhaustive information within conclusion section. In addition to this, please highlight the main contributions of this paper within introduction section as well. 

6. Better provide a table that share all acronyms along with their full description. 

Comments on the Quality of English Language

Re-read all paper to avoid some minor grammatical and punctuation errors. 

Author Response

Note: We uploaded the revised zip and pdf and additional through Supplementary Files a pdf with coloured changes: red text shows deleted text, blue text show new text.

Comment 1: The title is too philosophical please propose a title that shares the insights of a paper to some extend

Response 1: Thank you for taking the time to review our manuscript and providing your feedback. We appreciate your expertise and enthusiasm for our work.

Regarding the title, we understand your suggestion to make it more concrete and directly related to the content of the paper. However, after careful consideration, we would like to respectfully decline changing the title. While we agree that a more straightforward title might be more appealing to some readers, we believe that the current title accurately reflects the essence of our research.

The title "Increased Safety Goes Hand in Hand with Higher Cost Efficiency: Single Controller Operation Showcasing its Advantage" conveys the main theme of our paper, which explores the benefits of single controller operation in improving safety and cost efficiency. We believe that this title effectively captures the essence of our study and will resonate with readers who are interested in this specific topic.

That being said, we appreciate your feedback and would like to propose a minor revision to the title. While maintaining its original core message, we could add  a brief phrase that provides more context. For example: "Increased Safety Goes Hand in Hand with Higher Cost Efficiency: Single Controller Operation Showcasing its Advantage - A Human-in-the-loop simulation".

We value your input and would like to hear any further suggestions you may have on how to improve the title.

Comment 2: Within abstract author mentioned the staff shortage issue in a generic way, I mean there are number of other techniques to address the same issue so why someone will give importance to your suggested approach. Lack of novelty please improve abstract. 

Response 2: We refined the abstract to effectively integrate methodology and results within the 200-word limit, while strengthening the novelty of our concept. However, we were unable to incorporate additional approaches to address staff shortages due to space constraints. In Chapter 2, we provide a comprehensive comparison of these alternative methods with SCO, allowing readers to understand the rationale behind our approach.

Comment 3: Within the literature I suggest to summarise all such approaches addressing the staff shortage issue and or researchers who earlier introduced single controller along with their limitations and try to sync your arguments why you are proposing this and how it is different from previous approaches.

Response 3: In response to your suggestion, we have included a comprehensive comparison table (Table 1) in Chapter 2, which summarizes the key features and limitations of various approaches addressing the staff shortage issue. This table aims to provide a clear overview of the existing literature on this topic, highlighting the strengths and weaknesses of each approach.

Comment 4: In paper many of the sections and subsections are written in postulates form which is wrong approach to share your information in any technical form of writing. It is technical paper not a presentation please amend it

Response 4: Upon reviewing the manuscript, we have made an effort to rephrase and replace these sections with a more formal and technical tone. However, upon reviewing our revisions, we are still unsure if all instances of postulates have been fully replaced. We would like to request clarification on specific areas where the postulate format may still be present. Are there particular sections that require more attention?

Comment 5: Add exhaustive information within conclusion section. In addition to this, please highlight the main contributions of this paper within introduction section as well.

Response 5: The structure of the paper was detailed in the introduction section. The unique contribution of the paper to the research topic is highlighted following the research questions. We appreciate your suggestion to add more information to the conclusion section to make it more exhaustive. Upon reviewing other comments from reviewers, we also noticed that some have requested a shorter or more concise conclusion. In light of this feedback, we have revisited our conclusion section and made revisions to replace certain sentences with concrete results from our paper.

Comment 6: Better provide a table that share all acronyms along with their full description.

Response 6: Thank you for bringing this to our attention. We have indeed revisited the list of acronyms and definitions provided prior to the References section, as per the guidelines outlined in the MDPI template.

Comment 7: Re-read all paper to avoid some minor grammatical and punctuation errors.

Response 7: We've taken your feedback into consideration and have re-read the entire manuscript  to ensure that it meets the highest standards of grammar, punctuation, and clarity. We're confident that the revisions we made address any minor errors you may have identified, and we appreciate your diligence in double-checking our work.

Reviewer 3 Report

Comments and Suggestions for Authors

The article discusses important aspects related to optimization in air traffic management. The structure of the article is not appropriate. The article should include:

- literature review. Currently, the literature review focuses on aspects related to air traffic management. The research gap has not been demonstrated. Clear measures of safety, efficiency are not indicated. How other publications define these areas and why the authors will do better is not indicated.

- mathematical model. In their paper, the authors go straight to the analyses conducted. They present numerical results. What is lacking in the work is a general mathematical notation of the relationship between the level of safety and cost effectiveness. There is no definition of the variables of this model, no indication of the limitations of the model.

- case study. This part of the work is described in chapters 3 and 4. It would be necessary to structure this part of the work in relation to the chapter mathematical model. The notations of the mathematical model, variables and constraints on specific numerical values should be presented. It should also be indicated why the proposed approach is better than those presented in other scientific publications.

- conclusion. This part of the work does not need to be changed.

Very interesting article therefore I recommend it for thorough revisions in order to proceed with further publication.

Author Response

Note: We uploaded the revised zip and pdf and additional through Supplementary Files a pdf with coloured changes: red text shows deleted text, blue text show new text.

Comment 1: literature review. Currently, the literature review focuses on aspects related to air traffic management. The research gap has not been demonstrated. Clear measures of safety, efficiency are not indicated. How other publications define these areas and why the authors will do better is not indicated. 

Response 1: We have taken your comments into consideration and have made significant updates to our literature review section. Specifically, we have added subchapters dedicated to detailing measurements and methods used in existing literature related to air traffic management. Furthermore, we have included a summarizing table (Table 6) that provides an overview of the key methodologies employed by other publications in this field.

Comment 2: mathematical model. In their paper, the authors go straight to the analyses conducted. They present numerical results. What is lacking in the work is a general mathematical notation of the relationship between the level of safety and cost effectiveness. There is no definition of the variables of this model, no indication of the limitations of the model.

Response 2: We acknowledge that our manuscript jumps straight into the analyses conducted, presenting numerical results without background information on the mathematical relationships between the variables. We agree that a clear general mathematical notation of the relationship between safety and cost effectiveness would enrich our work. This limitation is now pointed out in the paper, as it is focusing on the validation excluding analytic models.  However, we have included (addressing your previous comment) literature to measurements applicable to our investigated variables and compared approaches. The variables addressed (safety, situational awareness, workload, operational efficiency, environmental impact and cost efficiency) all serve to prove the feasibility of the new SCO concept. Cost efficiency is automatically predetermined by the concept if the other variables show to acceptable and the concept to be feasible. Thus, it was not the aim of the study to show a correlation or any relationship between two variables. Instead, the title merely provides an insight into the results. There was also no theoretically substantiated assumption in advance. These clarifications are included now as well.

Comment 3: case study. This part of the work is described in chapters 3 and 4. It would be necessary to structure this part of the work in relation to the chapter mathematical model. The notations of the mathematical model, variables and constraints on specific numerical values should be presented. It should also be indicated why the proposed approach is better than those presented in other scientific publications.

Response 3: The limitation of not including a mathematical model is now pointed out in the paper, as it is focusing on the validation excluding analytic models.  Chapters 2, 3 and 4 now follow all the same structure addressing one variable after the other (safety, situation awareness, workload, operational efficiency, environment impact and cost efficiency).

Comment 4: conclusion. This part of the work does not need to be changed.

Response 4: In response to he other reviewer comments we have nevertheless adapted the conclusion section.

Reviewer 4 Report

Comments and Suggestions for Authors

1. Kindly avoid the terms 'we', and 'our' in the manuscript.

2. Kindly add the novelty part, methodology, and quantitative results in the abstract.

3. If the maximum declared capacity exceeds 100%, how the controller can manage the situation?

4. Provide the abbreviation for CPDLC.

5. The research question (d-f) needs to be removed from the manuscript.

6. The experimental design part (section 3.1) needs to be described clearly.

7. Graphical illustrations for the proposed framework can be added for better visualization.

8. A more detailed explanation is required for Figures 4-6.

9. The Operational Performance (And other aspects also) needs to be compared with any baseline methods for a better understanding of the proposed method.

10. Revise the discussion section with research findings and strengthen it with literature support.

11. Revise the conclusion with research findings and future directions. Trim the conclusion section.

12. The research questions need to be placed, where the questions were addressed.

 

Author Response

Note: We uploaded the revised zip and pdf and additional through Supplementary Files a pdf with coloured changes: red text shows deleted text, blue text show new text.

Comment 1: Kindly avoid the terms 'we', and 'our' in the manuscript.

Response 1: Thank you for pointing this out. We have reviewed the manuscript carefully and made sure to exclude the words 'we' and 'our' as per your feedback.

Comment 2: Kindly add the novelty part, methodology, and quantitative results in the abstract.

Response 2: We refined the abstract to effectively integrate methodology and results within the 200-word limit, while strengthening the novelty of our concept. However, we were unable to incorporate additional approaches to address staff shortages due to space constraints. In Chapter 2, we provide a comprehensive comparison of these alternative methods with SCO, allowing readers to understand the rationale behind our approach.

Comment 3: If the maximum declared capacity exceeds 100%, how the controller can manage the situation? 

Response 3: We deleted the corresponding phrase in brackets in Chapter 4.5 for simplification. Nevertheless, we still like to answer your question as follows: As ATM planning is inherently a forecast-only activity, it cannot be guaranteed that a specific amount of aircraft will not exceed the declared capacity due to factors such as weather, pilots, previous ATC units, and so on. Therefore, in operation, it can happen that on short notice, the declared capacity is exceeded.

The Supervisor, in cooperation with the flow management position, will regulate air traffic, but they can only act in anticipation of future events or react on current situation. A typical solution in operation for the time between the first exceedance of the declared capacity and the time the implementation of measures to decrease traffic below the declared capacity become effective is to request the ATCO working the sector in question as soon as possible for their agreement to temporarily exceed the declared capacity for a certain period.

This possibility is considered during the evaluation/setting of the declared capacity number, taking into account that 100+x% should be manageable by any licensed ATCO.

Comment 4: Provide the abbreviation for CPDLC.

Response 4: We have re-examined the list of acronyms and definitions provided prior to the References section, as per the guidelines outlined in the MDPI template. Notably, we have now included the phrase 'Controller-Pilot-Data-Link' (CPDLC) in its expanded form when it first appears in the text, accompanied by the corresponding acronym in brackets.

Comment 5: The research question (d-f) needs to be removed from the manuscript.

Response 5: 

Regarding your suggestion to remove research questions d-f from the manuscript, we would like to understand the reasoning behind this recommendation. While these questions were not addressed in the current paper, they are part of the validation study and has been published elsewhere, as stated in the manuscript. Our intention was to provide a comprehensive overview for readers, avoiding the impression an aspect of our research is overlooked.

Could you please elaborate on why removing these questions would be beneficial or relevant? We're eager to address any concerns you may have.

Comment 6: The experimental design part (section 3.1) needs to be described clearly.

Response 6: We apologize if the description of the experimental design in section 3.1 was unclear or missing key details. To clarify, we would like to request more specific feedback on what exactly is missing from this section that would help us better understand how we can improve it. That being said, we have included a graphic (Figure 2) in this section to provide a visual representation of the system used in validation, which may help provide additional clarity. Could you please let us know if there's anything else we can do to address your concerns and provide a more detailed explanation?

Comment 7: Graphical illustrations for the proposed framework can be added for better visualization.

Response 7: In response to your suggestion, we have indeed included two figures in our presentation:
One figure illustrates the technical structure of the framework in principle, providing a clear overview of the underlying architecture.
The other figure visualizes the participants' interface, showcasing how users will interact with the system. However, we are not sure whether this may fully address your request.

Comment 8: A more detailed explanation is required for Figures 4-6.

Response 8: We added separate explanations for all three figures prior their appearance.

Comment 9: The Operational Performance (And other aspects also) needs to be compared with any baseline methods for a better understanding of the proposed method.

Response 9: We have taken your comments into consideration and have made significant updates to our literature review section. Specifically, we have added subchapters dedicated to detailing measurements and methods used in existing literature related to air traffic management. Furthermore, we have included a summarizing table (Table 6) that provides an overview of the key methodologies employed by other publications in this field. Explicitly for operational performance, we have revisited and refined our description to enhance clarity.

Comment 10: Revise the discussion section with research findings and strengthen it with literature support. 

Response 10: Regarding the discussion section, we appreciate your suggestion to incorporate main results that support our discussion and provide relevant literature to bolster our arguments. Given the current state of research on single controller operation for this specific topic, we acknowledge that some results may not be directly comparable to existing literature. However, we have made a concerted effort to draw upon related areas of research and contextualize our findings as best possible. To further enhance the discussion, we would like to highlight that we conducted an initial exploration of certain topics in Chapter 4, where each variable's individual results were closely examined in relation to the related discussion. In contrast, Chapter 5 takes a more comprehensive approach, integrating insights from multiple areas to provide a holistic understanding of the topic.

Comment 11: Revise the conclusion with research findings and future directions. Trim the conclusion section.

Response 11: Given the current state of research on single controller opration it is hard to connect to research findings. However, we have revisited our conclusion section and made revisions to replace certain sentences with concrete results from our paper and carefully ammendet future directions.

Comment 12: The research questions need to be placed, where the questions were addressed.

Response 12: To address your suggestion, we have indeed included our research questions in the discussion section of the manuscript.

Round 2

Reviewer 3 Report

Comments and Suggestions for Authors

All my comments have been taken into account.

Reviewer 4 Report

Comments and Suggestions for Authors

Dear Authors,

Congrats.

In the earlier version, the RQs were not addressed comprehensively. Now it is enhanced.