NARSIM Simulations on Virtual Block Control and Separation Bubbles

During the last two weeks NLR successfully carried out simulations on Virtual Block Control and the use of Separation Bubbles for Taxiway Conflict Alerting under low visibility conditions. The project was carried out by AT-One, the ATM research alliance between the Dutch and German Aerospace Research Institutes NLR and DLR, for Eurocontrol, the European Organisation for the Safety of Air Navigation.
The objective of the project was to evaluate operational improvements that would support air traffic controllers in more efficiently and more safely handling airport ground traffic when visibility conditions are so bad that pilots cannot avoid collisions by looking outside the cockpit (VIS-3). Furthermore, it was assumed that there were no additional means in the cockpit that would increase pilot situational awareness, such as moving map displays.
In an earlier workshop with controllers from several European airports it was concluded that a concept for Virtual Block Control in combination with a safety net for separation (Separation Bubbles) would most probably be the most effective improvement for ground control under the specified conditions.
In order to evaluate the new tools and the associated operational procedures, the NARSIM Tower simulation environment of NLR was equipped with prototype virtual stop bars on a ground traffic radar display and appropriate alerting services for stop bar and separation violations. Rotterdam Airport (EHRD) was chosen as the geographic location as it was considered to have an ideal layout for evaluating all operational challenges when using the new tools. Above that the Rotterdam set-up was already successfully used for controller training.



Two teams of controllers (from Rotterdam and Stockholm) took part in the evaluation sessions that assessed operational procedures and, in a later stage, traffic throughput together with automation trust, impact on mental workload, situational awareness, and general system usability. Results will be reported to Eurocontrol in a final report at the end of this year. It is expected that Eurocontrol will publish that report in early 2009.

EMMA2 Airport Simulations (Milan)

In July 2008 real-time simulations for a safety assessment of the Milan Malpensa tower controller working environment were carried out with the NARSIM-Tower validation platform at NLR Amsterdam as part of the EMMA project.

The objective of the simulations was to obtain results that support a safety assessment of the Italian prototype A-SMGCS components developed within the project timeframe.



The following analysis methods were applied during the experiments:
- Observation and Improved Operational Expert Elicitation
- Insertion of Hazards in the Simulations
- Measurement of Parameters for Risk Uncertainty Reduction

Results of the real-time experiments will become available as part of the EMMA2 Validation Analysis Report at the beginning of 2009.

Skybrary

During this year's ATC Global exhibition Eurocontrol presented a new website called Skybrary. This website is an initiative of Eurocontrol, ICAO and the Flight Safety Foundation. It is supposed to become the most important point of reference when it comes to aviation safety knowledge.



Skybrary is set up as a wiki site allowing registered users to contribute to its contents. Apart from being a library of safety related terms the website currently provides three portals addressing different safety aspects. These portals try to categorise information for different purposes and different audiences. The main portal looks at operational issues and is a good reference for research in the aviation safety field in general. Two other portals focus on enhancing safety (e.g. through safety management and technology) and safety regulation.

While much of the information presented on the Skybrary website might already be available on the net, it is hoped that this effort will help in consolidating the knowledge under a single roof. From the point of view of R&D this is certainly met with approval and in the long run research results, especially in the category of operations and safety enhancing technology and methodologies, should find their way into this base of information.

ATC Global

This year the major European event in air traffic control known as ATC Maastricht moved to Amsterdam's RAI and consequently changed its name to ATC Global. With the exhibition area being almost twice as large as the one in Maastricht's MECC also the number of visitors seemed to have increased.

Some of the stands were quite impressive regarding the effort spent to give demonstrations of the latest developments in ATM technology. However, from a research point of view not much innovative tools and facilities were shown. Of course, there were highlights again from companies like Saab, AviBit , SELEX or Frequentis. They showed quite interesting tower control tools, such as Electronic Flight Strips (EFS) and Departure Managers (DMAN). Innovative developments, however, such as route planning and conformance monitoring were mostly not on public display yet, as some of these tools are either still in stages of development or not mature enough to be sold. And selling still is one of the major drivers of this exhibition.

AT-One presented themselves as one of the leading research alliances in Europe and caught much attention with their hourly demonstration of ASAS flights. These flights were carried out by two flight simulators, one from NLR and one from DLR, approaching Prague airport. Another great feature of the AT-One stand was the flexible NARSIM-Tower simulator which was displayed in a small, moveable version, however, with all the functionality of its larger brother at the NLR premises.

Although I might have missed some of the items at display in Amsterdam this year, as time was limited, there was a demonstration at the Eurocontrol stand that caught my attention: Skybrary. I will dedicate another post to this new aviation safety wiki site soon.

Requirements Engineering

Just at the start of the new year NLR finished a study for Eurocontrol investigating the role of requirements within the different life cycle phases of ATM operational concept validation as described by the European Operational Concept Validation Methodology (E-OCVM).

A survey of relevant standards (IEEE, ESA-ECSS, EUROCAE) and terminology related to operational concept validation and requirements engineering was performed. This survey resulted in a strategy for the development of requirements along the E-OCVM life cycle composed of three major processes called requirements elicitation or capture process, requirements analysis or specification process, and requirements management process.

The study describes the requirements strategy in detail and refers to the relevant standards that can be used as guidelines for the processes. An analysis of actors and their roles within the validation process emphasised the role of a central manager overseeing the development processes that lead to a gradual refinement of the requirements. Finally, the study analysed three European R&D projects regarding their requirements engineering processes and compared their approaches with the suggested strategy.

Thus, if you have lost your way in the underbrush of ATM standards and requirements documents, this study might be interesting reading material.

The report was published as NLR report CR-2007-702 and is publicly available.