45TH ANNUAL CONFERENCE, Kaohsiung, Taiwan, 27-31 March 2006WP No. 91Study Operations in a Paper Stripless EnvironmentPresented by TOC |
Introduction
1.1. The Technical and Operations Committee (TOC) has been requested to investigate stripless environments. This paper has been prepared to report the findings of this investigation.
Discussion
2.1. Stripless operations are starting to proliferate across the globe. Stripless operations exist in a variety of ATC environments. These range from large en-route centres to stand-alone towers.
2.2. Oceanic Control Centres
2.2.1. Oceanic centres were amongst the first ATC units to introduce stripless operations. For instance, the Prestwick Oceanic Centre first introduced a paper stripless environment in 1987. This system is now being replaced by a new generation stripless system, known as Shanwick Automated Air Traffic System (SAATS), which includes trajectory probing.
2.2.2. The task of providing ATC in some oceanic environments, such as the North Atlantic (NAT), is well suited to stripless operations. There are therefore many oceanic centres that operate using stripless systems.
2.2.3. The type of stripless operation varies between centres. For instance, in New Zealand a geographical display is not required for the oceanic operation, whereas in neighbouring Australia, the oceanic operation needs a geographical display.
2.3. Area Control Centres
2.3.1. There are several Area Control Centres (ACCs) that have been migrated during recent years from a traditional operation based on paper flight progress strips to a stripless operating environment. The stripless environments that exist can vary significantly from unit to unit.
2.3.2. The removal of paper flight progress strips can be facilitated by various types of stripless environment. These range from electronic strips, which are simply an electronic version of a flight progress strip, to data lines, to fully integrated electronic platforms incorporating Controller Tools (CTs).
2.3.3. One of the first en-route centres to remove paper flight strips was Maastricht UAC. This unit replaced paper strips with data lines and Touch Input Devices (TIDs). Since then, a new operations room has opened and the interactions with the electronic data are now via mouse or roller-ball.
2.3.4. The Amsterdam Advanced ATC System (AAA) at Amsterdam ACC is another example of a unit that uses a stripless operation. This environment has been in use for many years, as stripless operations were introduced prior to 1984.
2.3.5. Airservices Australia was one of the first Air Navigation Service Providers (ANSPs) in the world to successfully implement a new fully-automated Air Traffic Management (ATM) system. The Australian Advanced Air Traffic System (TAAATS) is a paper stripless operation that provides an improved efficiency in air traffic control and navigation services. TAAATS is claimed to be the world’s most advanced, integrated ATC system.
2.3.6. National Air Traffic Services (NATS) in the United Kingdom is intending to introduce stripless environments at its ACCs. A new platform is being introduced which will include advanced CTs. Functions such as Medium Term Conflict Detection (MTCD), Trajectory Prediction (TP) and deviation monitoring will all be provided in the new stripless environment, which is provided as part of the Future Area Controller Tools (FACTS). Data will be presented to the controller via interaction windows, rather than the more traditional electronic strip format.
2.3.7. There is a considerable amount of Research & Development activity being undertaken regarding stripless environments in various organizations. For instance, the French ANSP has been testing an advanced interface known as ERATO, whilst Eurocontrol have developed the ODID platform over a number of years.
2.4. Approach operations
2.4.1. Stripless operations are not used exclusively in the en-route environment. Some approach units are moving away from paper flight progress strips to electronic interfaces.
2.4.2. One of the main issues that needs to be overcome with the introduction of stripless environments at busy approach units and TMAs is the speed of data entry. The use of traditional pen and paper is a very effective way of quickly recording information, such as cleared levels, headings, and allocated speeds. Initially, difficulties may be encountered in electronic environments with match the speed of input that can be achieved with pen and paper. However, as controllers become familiar with the method of input, experience has indicated that speed of input can match or exceed that achieved by pen and paper. An example is Amsterdam ACC and the Australian TAAATS system.
2.5. Tower Operations
2.5.1. Stripless operations are gradually being introduced into aerodrome towers. For example, the Elimination of Flight Progress Strips (EFPS) system has been introduced in towers by both NavCanada and NATS in the UK.
2.5.2. Tower environments introduce a range of issues that are not necessarily encountered at an ACC. For instance, radar controllers tend to sit in front of a console in a relatively static position. By contrast, tower controllers are often on their feet and tend to move around considerably more than the radar controllers. This more physically dynamic role makes it harder to produce a stripless environment that is ergonomically correct for all the individuals that will work in that environment. The Human Machine Interface (HMI) will need to be suitable for use when both sitting and when standing. This in itself makes the design of the controller working position more challenging.
2.6. Issues
2.6.1. Stripless environment design
2.6.1.1. Electronic displays for ATC fall into four broad categories or into hybrids of these four techniques.
i Simple electronic data displays;
ii Emulated paper strips;
iii Electronic strips;
iv Dynamic electronic data reproduced within a graphical environment.
2.6.1.2. Emulated paper strips are strips that duplicate the same format as the original paper strip and have the advantage that their design, content and manipulation can be arranged to mirror the use of paper strips with benefits for conversion training. However, the pure emulation of paper strips can deny controllers many of the potential benefit of electronics, and intended operational benefits therefore tend to dictate that emulation alone is inadequate.
2.6.1.3. The use of graphical displays for dynamic data, including the presentation of interactions between tracks is well established in various systems. Trajectory prediction on advanced systems can be depicted on graphical displays, including both dedicated windows and the situational display itself. The same applies to conflict alerts, both short term and medium term. Future conflicts detected by Medium Term Conflict Detection (MTCD) are represented well by graphics.
2.6.1.4. Stripless environments should be designed with the objective to improve and enhance the data exchange for controllers. Such systems must provide accurate and incorruptible data. Stripless systems must be built with an integrity factor to review and crosscheck the information being received.
2.6.1.5. Stripless environments must assist and support ATCOs in the execution of their duties.
2.6.2. Displays
2.6.2.1. In general, the displays associated with stripless operations need to be fit for purpose. The information needs to be depicted in a clear and succinct way to ensure that the data is readily available and can be correctly interpreted.
2.6.2.2. Tower operations have some specific issues. Almost by definition aerodrome control is carried out in an environment where electronic displays are subject to more glare and reflection than in the closed environment of an operations room.
2.6.2.3. At night the same displays that needed to be suitable for the glare and reflection of the daylight environment must be equally effective when operating at reduced light levels.
2.6.2.4. Aerodrome control being a visual medium, requires more mobility from a controller than do other roles. The controller’s proximity to the electronic displays and the range and angle at and through which the display can be read are more critical.
2.6.2.5. Additionally the electronic strip displays need to be accessible by the controller regardless of the physical position that the controller is in, i.e. sitting or standing.
2.6.3. Controller interface
2.6.3.1. Flight progress strips capture, display and provide a record of data entries. Any electronic medium is required to do the same, but the technique may vary.
2.6.3.2. Data entry and manipulation needs to be simple and to impose an insignificant task load. Experience has shown that data entry can be a hurdle for the introduction of stripless operations to the Terminal Area (TMA) and approach environments. In complex, dense airspace, controllers are often fully engaged. There is no spare capacity to undertake additional tasks if such tasks are more complex than the operation of pen and paper. There is therefore a requirement for a simple, but effective and rapid means of data input for high density operations.
2.6.3.3. Electronics used intelligently can help the controller. For example, if the strip has fields for current time entries the strip system should already know the time, so all the controller would need to do is click the box, not type in the time. Any sequence of electronic processes routinely precipitated by that time entry ought then to be initiated without the need for any further controller action. The confirmation that those operations had occurred should be automatically fed back to the controller (or perhaps the controller is only told if the sequence failed and where, so that corrective action can be taken).
2.6.4. Systems interoperability
2.6.4.1. Once stripless environments are introduced, it will be possible to use the data that is available electronically to share the information with the wider ATM system. This shared information could be used by a number of other sub-systems. For instance, data entered in a tower should not need to be re-entered again for that flight within the domestic or regional ATM system.
2.6.4.2. With the advent in the near future of traffic management tools to produce, for example, optimum departure and arrival sequences for whole terminal areas it is essential that all data available is known to the network of management tools.
2.6.4.3. The introduction of advanced tools, such as Enhanced Mode S, will result in information being fed back into the ATM system by interactive aircraft. The aircraft derived data can be used to undertake automated comparisons. For instance, a cleared level could be checked against the selected level input by the flight crew. A difference between the 2 levels in this example would result in an automated alert being generated for the controller(s).
2.6.5. Human Factors
2.6.5.1. The introduction of stripless operations is likely to significantly change the way in which controllers work and the manner in which they undertake specific tasks will probably be amended. The human factors associated with a fundamental change in the way of working needs to be explored.
2.6.5.2. One particular area that may be adversely affected by the introduction of a stripless environment is situational awareness. The introduction of stripless environments may have potential degradation of the controller’s dynamic traffic model ”the picture” and the impact of any such degradation on the ability of a controller to honour existing responsibilities.
2.6.5.3. The extent of the change for controllers moving from a paper-based operation to a stripless environment will be determined by the type of stripless environment, i.e. a new environment featuring an electronic strip may be easier than moving straight to an entirely radar based operation.
2.6.5.4. The loss of physical triggers that exist with paper strips needs to be replaced by alternative triggers in a paper stripless environment. Such alternative triggers should be provided by the design of the stripless system.
2.6.5.5. Changes to the method of operations are required in order to get the maximum benefit from the stripless environment. Where there is a significant to the method of operations, a phased introduction should be considered.
2.6.6. HMI
2.6.6.1. In the UK any display system has to comply with the Display System Equipment (DSE) regulations 1992. The issues surrounding the introduction of work stations for the en-route environment tend now to be known. However, the tower environment still poses a range of issues that need to be addressed. Radar ATCOs operate sitting down whereas tower ATCOs especially ground movement controller, often need to stand up. Obvious perhaps, but a serious consideration when designing desks and display equipment that in terms of angle, distance and elevation to the user, must accord with the Display Screen Equipment (DSE) regulations. Some ATS providers have overcome the HMI problems in the tower environment by insisting that controllers are seated to undertake their tasks. This includes the ground movement controller, a position that is normally a dynamic one.
2.6.6.2. In general terms the HMI should be easy to use and it should be intuitive in design. This is particularly true if it is expected that stripless operations will replace paper strips.
2.6.7. Reversion
2.6.7.1. There is a potential for controllers to become reliant on the tools in a stripless environment. This could have adverse consequences. For instance, the controller’s ability to safely continue service provision in the event of a catastrophic system failure at peak periods needs to be retained.
2.6.7.2. Total workload should not be increased without proof that the combined automated/human systems can operate safely at the levels of workload predicted, and to be able to satisfactorily manage normal and abnormal occurrences.
2.6.7.3. A stripless environment must enable the controller to retain complete control of the control task in such a way so as to enable the controller to support timely interventions when situations occur that are outside the normal compass of the system design, or when abnormal situations occur which require non-compliance or variation to normal procedures.
2.6.7.4. Some ATS units practice fall-back procedures on a regular basis. For instance, the Shanwick Oceanic Centre practices a reversionary operation once per month, including the loss of their OLDI links, where paper strips are used.
2.6.8. Training
2.6.8.1. It should be noted that some of the older generation of controllers may take longer to adjust to a stripless operation than newer members of the team.
2.6.8.2. Additional continuation training shall be provided to enable controllers to practice manual control techniques with live and/or simulated traffic to maintain their skills levels.
2.6.9. Legal aspects
2.6.9.1. The legal aspects of a controller’s responsibilities must be clearly identified when working with a stripless system.
2.6.10. Advantages
2.6.10.1. Besides all the issues that need to be addressed prior to implementation as listed above, there are substantial benefits that can be gained from paper stripless operations. These include:
- Reduced head-down time;
- Improved data transfer; and
- Enhancements to CTs and Safety Nets because data fusion.
Conclusions
3.1. Operations in a paper stripless environment can be advantageous to ATC, however there are a number of issues that need to be considered. Some of these issues are specific to the various ATC environments.
3.2. Stripless environments must assist and support ATCOs in the execution of their duties.
3.3. The proposed introduction of a systemised environment will require in each case a formal operational, human factors and regulatory review of the impact on the future role and responsibility of controllers.
3.4. Consideration should be given to further study the legal issues pertaining to paper stripless environments by PLC.
Recommendations
It is recommended that;
4.1. This paper is accepted as information material.
Last Update: September 29, 2020