The CREDOS Project Human Machine Interface Design Abstract This deliverable presents the first stage of the design and development of a Human Machine Interface (HMI) to support CREDOS operations. This document describes the methodology that is being used to define the HMI requirements and develop potential HMI design solutions for CREDOS. A summary of those activities that have been conducted to date is provided and activities planned for the future outlined. The different design alternatives and options that have been developed to help define the requirements specification for the CREDOS controller HMI are then presented. This document is accompanied by an annexed video file which presents one HMI design option for CREDOS. Contract Number: AST5-CT-2006-030837 Proposal Number: 30837 Project Acronym: CREDOS Deliverable: D4-5 Delivery Date: T15 Responsible: EUROCONTROL Nature of Deliverable: Report and CD-Rom Dissemination level: Public File Id N : CREDOS_410_ECTL_DLV_D4-5_HMI.doc Status: Approved Version: 1.0 Date: 18/06/2008 Approval Status Document Manager Verification Authority Project Approval EEC NLR PMC Anna Wennerberg Lennaert Speijker PMC members Sub WP Leader WP4 Leader 1
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Executive summary The aim of the CREDOS project is to investigate the feasibility of relaxing the ICAO Wake Turbulence Separation that is normally required between departing Heavy and Medium aircraft under certain crosswind conditions. It is proposed that the suspension of this separation can take place when there are sufficient cross-winds to move the wake vortices out of the path of the following aircraft trajectory. This deliverable presents the first stage of the design and development of a Human Machine Interface (HMI) to support CREDOS operations. This document describes the methodology that is being used to define the HMI requirements and develop potential HMI design solutions for CREDOS. A summary of those activities that have been conducted to date is provided and activities planned for the future outlined. The different design alternatives and options that have been developed to help define the requirements specification for the CREDOS controller HMI are then presented. This document is accompanied by an annexed video file which presents one HMI design option for CREDOS. This deliverable is the first step towards defining the CREDOS HMI specifications that will be developed for the real time simulation due in 2009. This document covers only the Tower Runway Controller working position. 3
Table of Contents EXECUTIVE SUMMARY...3 1. INTRODUCTION...7 1.1 Background...7 1.2 Purpose and scope...7 1.3 Document structure...8 1.4 References...8 2 HMI DEVELOPMENT PROCESS...9 2.1 HMI related activities conducted to date...9 2.1.1 Human factors issue analysis (HFIA)...9 2.1.3 Preliminary HMI design...9 2.1.4 Task analysis...9 2.1.5 Preliminary stakeholder workshop...10 2.1.6 Field studies...10 2.1.7 Alternative HMI design options...10 2.2 Future planned HMI related activities...11 2.2.1 Prototyping sessions...11 2.2.2 Part-task real time simulation...11 2.2.3 Real time simulations...11 2.3 Overview of HMI design and development process...11 3 INITIAL HMI DESIGNS...12 3.1 Simple CREDOS HMI...13 3.1.1 Information presented...13 3.1.2 Assumptions...13 3.1.3 Description...13 3.2 Advanced CREDOS HMI...14 3.2.1 Information presented...14 3.2.2 Assumptions...14 3.2.3 Description...15 3.3. Additional CREDOS HMI options...17 3.3.1 Manual digital timer...17 3.3.2 Wind and crosswind indication Option 1...17 3.3.2 Wind and crosswind indication Option 2...18 4 CONCLUSIONS...20 4
List of Figures FIGURE 1. OVERVIEW OF THE CREDOS HMI DESIGN AND DEVELOPMENT PROCESS 11 FIGURE 2. CREDOS HMI SIMPLE SOLUTION.13 FIGURE 3 CREDOS HMI ADVANCED SOLUTION...14 FIGURE 4 DESCRIPTION OF THE CREDOS ADVANCED HMI - WHEN CROSSWINDS ARE CREDOS COMPLIANT 15 FIGURE 5 DESCRIPTION OF THE CREDOS ADVANCED HMI WHEN CROSSWINDS ARE NOT CREDOS COMPLIANT....16 FIGURE 6 MANUAL DIGITAL TIMER 17 FIGURE 7 WIND PLUS CROSS WIND INFORMATION DISPLAY FOR RUNWAY CONTROLLER S CWP.... 18 FIGURE 8 METEO INFORMATION DISPLAY FOR RUNWAY CONTROLLER S... 18 FIGURE 9 WIND & CROSSWIND INFORMATION INTEGRATED INTO METEO WINDOW 19 5
List of Acronyms CREDOS A-SMGCS HFIA HMI EC ERC NLR PMC U/S ICAO TL RWY Crosswind REDuced separations for Departure OperationS Advanced Surface Movement Guidance Control System Human Factors Issue Analysis Human Machine Interface European Commission EUROCONTROL National Aerospace Laboratory-Netherlands Project Management Committee Unserviceable International Civil Aviation Organization Transition Level Runway 6
1. Introduction 1.1 Background Increases in air traffic over recent years have resulted in congestion at many airports. The need to increase airport capacity is one of the major challenges facing ATM research today. One potential means of increasing airport tactical capacity is to reduce the wake vortex separation distances between aircraft. The aim of the CREDOS project is to develop and validate a new operational concept that would allow the current ICAO Wake turbulence separation that is normally needed for a Medium aircraft following a Heavy to be relaxed under certain crosswind conditions. It is proposed that the suspension of the 2 minute runway separation normally required can take place when there are sufficient crosswinds to move wake vortices out of the path of the following aircraft trajectory. 1.2 Purpose and scope This document is deliverable D4.5, HMI design, which has been developed as part of WP4.1. WP4.1 concerns the development of the initial Concept of Operations, its refinement during the project and the specification of controller working methods and tools, including HMI design. This deliverable is the first step towards defining the requirements for the CREDOS HMI that will be developed for the real time simulation due in 2009. This document has several aims: to describe the methodology that is being used to identify and define the HMI requirements and develop potential HMI design solutions for CREDOS, to provide a summary of the activities that have been conducted to date as part of the HMI development process. to present the different design alternatives and options that have been developed to date and that will be used to help define the requirements specification for the CREDOS controller HMI. The aim of D4.5 is to develop a HMI design specification for CREDOS that will be used in the CREDOS real time simulation in April 2009. However, findings from field studies that are being conducted as part of the CREDOS HF case (2.1.6.) show that one of the difficulties in developing HMI for ATC is the lack of standardisation in the way data is presented. As a result different airports often use different display formats, colours and fonts. Therefore, the specification of HMI displays will focus more on the information that is to be presented and its mechanization than on its specific appearance. The CREDOS concept is still in the early phases of development. The HMI information requirements including alerts and information input requirements are dependant on the CREDOS concept of operations and hence operational and system requirements which are in the process of being further developed. Therefore, the HMI design solutions and options presented in his document are based on the information that was available regarding the CREDOS concept and functional description before the end of 2007. It should be noted that the alternative design options presented in this document are being used to help further refine and define the HMI requirements for CREDOS. Thus they are not meant to be definitive solutions in themselves but rather a means to help the CREDOS HMI requirements be identified and defined. This deliverable presents two possible design alternatives: one that is very simple providing controllers with the minimal amount of information required for CREDOS operations and; another that is relatively sophisticated, which introduces automation support to aid controllers with CREDOS Operations. Further more, additional information and HMI design options have 7
been identified and these are also presented in this document. The simple and advanced HMI alternatives together with the various information and presentation options will be used to help identify and refine the HMI requirement specification for CREDOS. Thus this document is a working document which will be continuously updated and amended throughout the project. A 10 minute video file which presents the advanced CREDOS HMI design alternative accompanies this document (see Annex 1), as part of deliverable 4.5. This first deliverable will only consider CREDOS HMI solutions for the runway controller. HMI solutions for other system actors including the supervisor, ground controllers, departure controllers and possibly maintenance / technical staff will be considered at a later date. However, it should be noted that wherever possible, HMI solutions for other actors should be consistent with the HMI developed for the runway controller to help transferability of knowledge and skills. 1.3 Document structure The document is structured as follows: Section 1: Introduction, explaining e.g. the purpose of this document. Section 2: HMI development process Section 3: HMI designs Section 4: Conclusions and future work 1.4 References 1. Validation Strategy and Plan (CREDOS D4.3), including Appendix B (CREDOS Human Factors Action Plan). 2. Initial concept (CREDOS D4-2). Initial CREDOS Concept of operations version A. CREDOS_410_ECTL_DLV_D4-2_CONops. 3. CREDOS task analysis for tower control, Nov. 2007 (ECTL internal document) 4. Preliminary CREDOS stakeholder workshop note, CREDOS_500_ECTL_MOM_workshop Nov 2007 5. CREDOS Functional Hazard Assessment (CREDOS D4.6). 8
2 HMI development process A participatory design process is being used to develop the HMI requirements for CREDOS. This means that operational expertise will be sought throughout the design and development process to help ensure that the HMI requirements and specifications are operationally usable and acceptable. However, ensuring acceptability and usability is never guaranteed as different controllers can have very different ideas and opinions, even if they come from the same operational environment. Therefore, the design process will use a combination of subjective and objective methods to help mitigate subjective biases that may occur. The development of the HMI (and CREDOS concept as a whole) is an iterative process which involves a series of validation activities. Each validation activity in the HMI design and development process helps to define CREDOS HMI requirements. From these requirements potential HMI design solutions are developed. These design solutions are then used in subsequent validation activities to further refine the design requirement specifications for the CREDOS HMI. As the concept matures, the fidelity of the validation activities increases. The validation activities that have been conducted to date and the findings from these activities are summarized below. 2.1 HMI related activities conducted to date 2.1.1 Human factors issue analysis (HFIA) A preliminary HFIA was performed in May 2007 with 5 participants, including 4 controllers and one pilot plus a HF expert and a mediator. The main input to the HFIA was the CREDOS Concept of Operations version A (Ref. 2). The Human factors issues analysis uses a structured brainstorming technique to identify potential issues that may arise as a result of introduction of CREDOS operations. Subsequently, recommendations for mitigating these issues are identified. (see Ref. 1 for details). Many of the recommendations identified from the HFIA were related to HMI design. 2.1.3 Preliminary HMI design The HMI recommendations and requirements identified from the HFIA were used to develop the preliminary CREDOS HMI design specification (presented in section 3.2). The HMI developed from the HFIA recommendations is sophisticated in its design, as it integrates a CREDOS availability indicator with an automated timer (activated by the movement of an aircraft detected on the SMR) that helps controllers accurately time aircraft separations when CREDOS operations are permitted. As a result, this HMI is the advanced HMI solution. The advanced CREDOS HMI solution has been animated and can be seen in video format in Annex 1.0. 2.1.4 Task analysis A tower control task analysis was conducted to identify changes to the controllers tasks and working methods that would result from the introduction of CREDOS operations, (see Ref.3), from these changes, HMI information requirements can be identified. Task analysis covers a range of different techniques and can generally be defined as a methodology used to help breakdown and describe operators (e.g. controllers) tasks in terms of the actions and /or cognitive processes that are required, to achieve a system goal. The information obtained from the task analysis can then be used to make judgements or design decisions. A baseline task analysis of tower controllers current tasks and working methods plus the latest version of the concept operations available at that time (CREDOS ConOps version A) were used to identify these changes. From these changes HMI information requirements for the runway controllers were identified together with HMI related design recommendations. 9
2.1.5 Preliminary stakeholder workshop A preliminary stakeholder workshop was held in November 2007. The workshop participants came from a diverse range of backgrounds including controllers, pilots, concept developers, safety and HF experts. The main aim of the preliminary stakeholder workshop was to gain feedback on the CREDOS concept in general and also the advanced CREDOS HMI that had been developed from recommendations and requirements identified through the HFIA. The CREDOS HMI was demonstrated using a video file which simulates the dynamic flow of departing aircraft as seen on an A-SMGCS ground movement radar display monitored by a runway controller using a Beta -version of the CREDOS demonstrator. The main feedback from controllers regarding the CREDOS advanced HMI was to keep the HMI as simple as possible. The stakeholder workshop also emphasised the importance of learning from current working practice and where possible building on and/or integrating tools and working methods that are currently used by controllers to support them in their work. This would not only help to ensure the proposed HMI is usable in the real world but will also help promote acceptability in the support tools / HMI developed. (see Ref. 4 for details of workshop feedback). 2.1.6 Field studies A survey is currently being conducted to investigate current controller working practices in European tower control centres. The aim of this survey is twofold: 1. to identify current controller working practice to help inform the CREDOS operational procedures and ensure that the proposed CREDOS procedure integrate well with current working practices. 2. to identify best practice, i.e. support tools and techniques currently employed, to perform their tasks well. This would help to identify further requirements and also give ideas about how the HMI requirements could be realised. The initial findings from the surveys obtained to date show that one of the difficulties in developing HMI for ATC is the lack of standardisation in the way data/information is presented. Different airports often use different display formats, colours and fonts. As a result the specification of HMI displays will focus more on the required information that is to be presented and its mechanization than on its specific appearance. (This activity is still in progress so no document is reference document is currently available) 2.1.7 Alternative HMI design options The feedback and findings from the task analysis, preliminary stakeholder workshop and field studies plus the functional hazard assessment (FHA) conducted by NLR (Ref. 6) were used to develop alternative HMI options for CREDOS. As recommended in the stakeholder workshop a simplified version of the CREDOS HMI was developed. This simple HMI presents controllers with what is considered the minimal amount of information required for safe CREDOS operations, the simple HMI is presented in section 3.1. In addition, a number of additional HMI information display options that may be required to support the controllers in their work (see section 3.3 for details). The design of these additional display options is based on tools currently used in some tower control, e.g. the 2 and 3 minute wake vortex timer that is used in Paris, CDG. Therefore, the HMI activities that have been conducted to date have resulted in: 1. a simple HMI design for CREDOS which presents the minimal information required by controllers to ensure the safe application of CREDOS operations 2. an advanced / sophisticated HMI where the CREDOS availability indicator is integrated with an automated timer 3. a number of additional HMI information displays and / or support options that may be required to support controllers in the application of CREDOS operations. The simple and advanced CREDOS HMI that have been developed and the additional HMI options will be implemented onto a simulation platform and evaluated in prototyping sessions planned to take place in June/July 2008. 10
2.2 Future planned HMI related activities 2.2.1 Prototyping sessions Prototyping sessions are planned to take place in June /July 2008. The advanced and simple CREDOS HMI design alternatives together with the additional information display options (described in section 3) will be implemented onto the integrated tower working position (ITWP). The ITWP is a prototype which integrates ground radar (A-SMGCS), approach radar, metrological information, electronic flight strips, lighting panel etc. into on integrated controller working position. The ITWP uses the edep simulation environment that has been specifically developed for prototyping and usability testing. The aim of the prototyping sessions is to gain feedback from controllers regarding the utility and usability of the advanced and simple CREDOS HMI alternatives plus the additional HMI information / support options. This feedback will be used to help further define the CREDOS HMI requirement specifications for CREDOS. 2.2.2 Part-task real time simulation Planned to take place November 2008. The objectives of this simulation have yet to be defined. 2.2.3 Real time simulations Planned to take place April 2009. The objectives of this simulation need to be further defined but the high level goal will be to assess the overall feasibility and acceptability of the CREDOS concept in terms of HMI, working procedures and workload. 2.3 Overview of HMI design and development process Figure 1 below gives an overview of the HMI design and development process together with the timeline for the HF activities. This illustration defines the human factors activities that will be conducted together with the required inputs for each activity and their outputs. Activity Timeline INPUTS HF activities Outputs Sept 2007 CREDOS ConOps Human Factors Issue Analysis Preliminary HMI requirements & recommendations Preliminary HMI design Dec 2007 Jan 2007 June 2008 Preliminary HMI design ConOps + Preliminary HMI design Preliminary Stakeholder workshop + Task analysis + Field studies Additional requirements & recommendations Additional requirements & recommendation Implementation ideas, recommendations Alternative HMI design options Aug 2008 HMI design Prototyping Refined HMI requirements & HMI options Nov. 2008 Refined HMI requirements Part-task RTS HMI requirements specification for RTS April 2009 HMI requirements RTS HMI acceptability / usability assessment Figure 1. Overview of the CREDOS HMI design and development process 11
3 Initial HMI designs This section presents the different HMI design alternatives and options for CREDOS. As described previously, both a simple and a sophisticated/advanced CREDOS HMI have been developed together with a number of additional HMI information display options. The different HMI options have been developed from recommendations and requirements obtained from the HMI activities conducted to date (see section 2.1 for details). Subsequent activities will systematically assess the utility and usability of the advanced and simple HMI designs plus the additional information display options, to help better define the HMI requirements for CREDOS. The scope of the HMI designs proposed in this document is: for the runway controller working position only based on a case by case scenario related to each runway separate from the wind presentation on each runway SID information is not considered, i.e. the light display conditions do not change if aircraft behind the heavy takes the same SID. 12
3.1 Simple CREDOS HMI 3.1.1 Information presented The proposed simple HMI solution for CREDOS is illustrated below. It will present the following information to the runway controller: whether CREDOS operations are permitted when CREDOS operations are no longer permitted whether some of the equipment is in failure mode, so that the crosswind information is not reliable (display ERROR or U/S ). This CREDOS availability window is linked to each runway. If a departure runway changes, the corresponding window must be displayed. RWY 09R/ CREDOS CREDOS ON RWY 09R/ CREDOS CREDOS OFF ACK RWY 09R/ CREDOS ERROR Figure 2. CREDOS HMI simple solution 3.1.2 Assumptions The CREDOS simple HMI solution is based on the assumptions that: The supervisor will receive information to inform him/her that the crosswind conditions are such that CREDOS operations can be applied. If the supervisor decides to permit CREDOS operations s/he will trigger a switch that will result in the CREDOS ON window being presented on all CWPs in the tower Likewise, the supervisor will receive information to inform him/her that the crosswind conditions are no longer appropriate for CREDOS operations. As soon as this information is received the supervisor will de-activate CREDOS operations by triggering a switch that will result in the CREDOS OFF window appearing on all CWPs 3.1.3 Description When the crosswind conditions are such that CREDOS operations can be applied the supervisor will decide whether to permit CREDOS operations or not. If the supervisor decides to permit CREDOS operations a switch will be triggered that will result in the CREDOS availability window being presented on all CWPs in the tower. The CREDOS window presents the runway on which CREDOS operations are permitted together with the words CREDOS ON in larger blue capital letters. To deactivate CREDOS operations e.g. for example if the appropriate crosswind conditions no longer apply, the supervisor will trigger a switch which will make the CREDOS OFF window appear on all CWPs. Controllers will have to acknowledge the de-activation of CREDOS operations by clicking on the acknowledge button in the centre of the CREDOS OFF window. Once acknowledged the CREDOS OFF window will disappear from the CWPs. Each controller must acknowledge the CREDOS OFF window to make it disappear from their CWP. 13
3.2 Advanced CREDOS HMI 3.2.1 Information presented The proposed advanced HMI solution for CREDOS is illustrated below. It will present the following information to the runway controller: whether CREDOS is active or not (if not, display Not in operation ), when CREDOS is active, i.e. whether reduced separation can be applied or not, through the means of a colour-coded GO/NO-GO display. The colour will depend on what information is integrated with the CREDOS coding, e.g. the colour of the GO light may be blue or green: if the light codes only the CREDOS separation applicability, but does not integrate other information on runway availability (e.g. runway incursion), it is preferable not to use green colour. The counter is re-initialised at each a/c departure, be it Heavy or not. If the departing aircraft is not a Heavy, the counter increments, but without colour coding. a timer integrated within the GO/NO-GO display, that helps planning the controller activity. the information of CREDOS non-applicability is only available after 1 minute following the Heavy aircraft departure. whether some of the equipment is in failure mode, so that the crosswind information is not reliable (display ERROR or U/S ). This information is displayed in a specific Wake Timer window linked to each runway. If a departure runway changes, the corresponding window must be displayed. R WY 19 / Wake Timer RWY19 / Wake Timer R WY 19 / Wake Timer RWY19 / Wake Timer RWY19 / Wake Timer 6 0 60 6 0 45 0 15 45 1 15 45 2 15 NOT IN OPERATION ERROR or U/S 30 30 30 Figure 3. CREDOS HMI advanced solution (N.B. Tick marks shall be displayed for every second on the countdown light, so that the pointer moves second by second from one tick to another. The numbers (15, 30 ) may not be necessary). 3.2.2 Assumptions The CREDOS advanced HMI is based on the following assumptions: 1. Aircraft start of rolling is automatically detected (e.g. passing a specific point) without need for a controller specific action. 2. Accurate crosswind information is received with a periodicity that ensures safe CREDOS departures (maximum 1 second To be decided). 3. The time period during which the crosswind must be CREDOS compliant to allow reduced separation, is a parameter set here to 60 seconds. It may show necessary to increase this value in order to provide a supplementary time buffer for the sake of a more safe situation, even if detrimental to the expected benefits. 14
3.2.3 Description In a separate window on the ITWP A-SMGCS display a minute counting timer is shown. The timer is supposed to start automatically when a departure roll is detected (probably the ground movement radar is best fit to detect this but other ground based sensors could be used as well. The wake vortex category of the departure is also recognized by the system. Depending on the crosswind component criterion that has been determined the timer will either show countdown to the CREDOS approved time spacing or the ICAO 2 minute separation. When the timer is still in a no-go phase it will show an orange background in order to signalize caution and when the timer is displaying CREDOS go phase it will be blue in order to signalize the CREDOS opportunity to reduce separation (therefore only initialized after Heavy departure). In all other cases it will be neutral = white. (The CREDOS advanced HMI as described is illustrated below in figures 2 and 3) Figure 4. Description of the CREDOS advanced HMI when Crosswinds are CREDOS compliant 15
Figure 5. Description of the CREDOS advanced HMI when Crosswinds are not CREDOS compliant 16
3.3. Additional CREDOS HMI options 3.3.1 Manual digital timer 3.3.1.1 Information / support tool A manual timer could be of use to support controllers in their task of timing separation between aircraft pairs. The timer is presented in digital format and counts down from the specified time selected, that is, either 1, 2 or 3 minutes. 1 MIN TIMER 2 MIN 3 MIN X 0:59 Figure 6. Manual digital timer 3.3.1.2 Description The manual digital timer presented here is based on the timer that is currently used in CDG tower control to help time 2 and 3 minutes wake vortex aircraft separations. When the controller requires support to time 1, 2 or 3 minute separations between an aircraft pair the controller clicks on the 1, 2 or 3 minute text box in the timer window using the left hand button of the mouse. The digital timer then counts down in seconds from one minute until zero. 3.3.2 Wind and crosswind indication Option 1 With the introduction of CREDOS the runway controllers may need detailed wind and crosswind information to be able to cross-reference other CREDOS related indications. Option 1 proposes that wind and crosswind information is displayed independently from the other meteo information. 3.3.1.1 Information When selected the wind / crosswind HMI display would present the following information to the runway controller: The runway number, runway presentation and use (i.e. take-off or Landing): the current wind orientation and speed (values on top left/right of the window, and arrow on the compass), the variation of the wind direction over the last 10 minutes (clear line inside the compass), with numeric indication of both extremes, and over the last 2 minutes (blue line inside the compass), the speed of the Front (as on this example) or Tail component of the wind, with respect to the runway (bottom left of the window), the Crosswind speed and direction with respect to the runway, i.e. blowing from the Right or from the Left (values on bottom right of the window, and arrow next to the runway). 17
RWY 19 WIND Direction 250 Take-off 360 330 30 Speed 06 kt 300 320 60 270 04 90 Front 240 230 120 210 150 180 03 kt 04 Cross kt R Figure 7. Wind plus cross wind information display for runway controller s CWP RWY 19 MET INFO Visibility, Weather, Temperature, Pressure + TL Figure 8. Meteo information display for runway controller s CWP 3.3.2 Wind and crosswind indication Option 2 Option 2 proposes that wind and crosswind information specific to the runway(s) in use is integrated into the existing meteo window and displayed with the other weather information available. It should be noted that many tower control already present this wind and crosswind information with the other meteo information. 3.3.2.1 Information The MET window contains weather information including wind and crosswind information. The meteo information window is only displayed on controller request. In normal format, the MET information window displays: surface wind direction (Touch Down) and strength in graphical (compass) and text, QNH (in hectopascals or millibars (same value)), ATIS code (letter designation) and issued time Temperature and dew point in degrees Celsius Cross winds (X-wind) and tail winds in knots. the runway and the runways orientation 18
Figure 9. Wind and crosswind information integrated into meteo window 19
4 Conclusions A number of design recommendations and requirements have been identified through the HMI developed activities conducted to date. The different HMI options presented in this document are just one way these recommendation and requirements can be realised. The simple and advanced CREDOS HMI design options plus the different HMI information / support options are not meant to be definitive HMI solutions in themselves, but a means by which the CREDOS HMI requirements and design specifications can be further defined. Initial prototyping sessions / usability testing is due to commence late June. The aim of these prototyping sessions is to present and gain feedback from controllers regarding the utility and usability of the advanced and simple CREDOS HMI alternatives plus the additional HMI information / support options. This feedback will be used to help further define HMI requirement specifications for the first CREDOS Tower real time simulations that will be conducted at NLR in November 2008 and April 2009. Future work regarding the CREDOS HMI will investigate the potential need for an upwind / downwind SID interface as new HMI solution for the runway controller. Further HMI solutions for other system actors including the supervisor, ground controllers, departure controllers and possibly maintenance / technical staff will be developed in due course. 20