Projects

Even with today’s downturn in global economics, TMA airspace is still generally regarded as being busy and complex. Although some initiatives, such as P-RNAV and CDAs, are bringing benefits today, it is felt that more is needed in the transition towards SESAR.

In the current European scenarios there are several initiatives intended to decongestion the TMA and support the traffic management in this area. These initiatives mainly focus on the investigation of the possible benefits associated to the introduction of:

• some basic Arrival Managers (AMANs), that generally operate in more-or-less a ‘stand-alone’ manner, with the purpose to assist in the coordination and the efficient sequencing of aircraft to an airport.
• advanced form of arrival management, which would integrate airspace design, aircraft capability, CDAs and new ground-system support tools, could provide this missing element.
• new techniques for handling air traffic. One of these new techniques is Point Merge System (PMS), an airspace design and associated method of working which aims to maximise the use of FMS navigational capability currently available and to provide flight efficient descent for arrival flights.

What is lacking at the moment is an insight into how these new proposals can integrate with current systems and to see if this integration has additional impacts, either on the current systems, or on the new proposals.
To investigate these integration issues, and to assist in the formulation of the new EUROCONTROL Guidelines for the AMAN introduction and usage, a TMA Partnership Project activity has been put in place and funded by EUROCONTROL. This activity falls under the name ‘TMA 2010+ Project South’ and is conducted in association with ENAV, SICTA, Deep Blue and BARCO.
The key elements under evaluation in this activity are the implementation of an AMAN system and concept, the use of PMS for the traffic to Rome Fiumicino airport and the integration of these two operations.
The expected benefits achievable from both these elements are a)increased standardisation of the inbound traffic management, b) improved predictability of the inbound traffic management, c) anticipation of the sequence building and d) easier management of traffic peaks.
As consequence possible reduction of Air Traffic Controller workload, more efficient flight trajectories and more efficient delay sharing are expected. In order to evaluate the actual impact of AMAN, PMS and of their combined used in Rome TMA two large scale real-time simulation are planned at ENAV Experimental Centre in Rome, respectively in March and November 2009.

Deep Blue Role

In the TMA 2010+ Project South Deep Blue is responsible for the management of the validation activities associated to the organisation, preparation, conduct and report of the real-time simulations.
The assessment of the possible effects of introducing AMAN, PMS and a combination of AMAN and PMS in the Rome TMA focuses on 4 KPAs, namely operability, flight efficiency, capacity and safety. The CRIA© Validation Approach guides the whole validation process, being used for the investigation of aspects such as operability and safety (to which it is basically targeted), as well as the other aspects of interest, namely flight efficiency and capacity.  

Outcomes of the RTS1

The first real-time simulation foreseen in the framework of the TMA 2010+ Project South was carried out at ENAV Experimental Centre in March 2009. It consisted in a large scale real-time simulation, in which a team of 12 air traffic controllers from the four Italian ACCs and 10 pseudo-pilots were involved.  
The RTS1 produced a large set of results on the possible impact that the new tools/methods of inbound traffic management (namely AMAN, PMS and a combination of AMAN and PMS) could have on the current operations of Rome ACC.
In theory all the tools/methods investigated were expected to positively impact on the process of inbound traffic management. In different ways they were supposed to (a) anticipate and standardise the inbound traffic management, (b) favour the cooperation among TMA and E-TMA controllers, (c) increase the predictability of the traffic evolution, (d) introduce benefits in terms of controllers’ workload and situational awareness, (e) increase the flight efficiency, (f) allow a better exploitation of the runways capacity.
The outcomes of the RTS1 did not fully confirm this hypothesis. On the contrary they revealed that the way the three tools/methods were designed and used during the study tended to affect their own capacity to satisfy the expectations above.

Considering the aspects of operability PMS seems presenting the most positive results.

The RTS1 highlighted a very good level of operability of PMS in both TMA and E-TMA sectors. The controllers involved in the study found the method comfortable, safe, accurate and easy to learn and to apply. In very short time they became familiar with it and able to apply it properly and effectively, even under high traffic load and in case of non nominal events. They considered the new technique suitable to and easy to accept in Rome TMA and E-TMA sectors. They also tended to perceive it as the evolution of the current method based on radar vectoring as result of the introduction of the PRNAV capability, rather than as a radical revolution of the arrival traffic management.

In their opinion the adoption of this method is likely to yield the following advantages:

• standardisation of the controllers performances, thus implying a standard high quality of the traffic management, less conditioned by personal skills and one’s own tolerance of traffic density and complexity
• improved teamwork not only within the TMA but also between TMA and E-TMA, since the standardisation of the work allows to predict and anticipate the colleague’s behaviour, expectations and needs
• general reduction of controller cognitive workload in all TMA sectors, since the standard way of managing the arrival traffic simplifies the work and reduces the need for problem solving, continuous monitoring, R/T and phone communication
• general high level of job satisfaction in both TMA and E-TMA controllers. For the first ones the less creativity required to manage the arrival traffic is counterbalanced by evident positive results in terms of flight efficiency and usage of runway capacity. For the other ones the main reason of satisfaction is the effectiveness of the traffic pre-sequencing that they carry out almost autonomously.

They also confirmed some possible drawbacks of the PMS technique that have been also highlighted during the prototyping sessions. Among the drawbacks detected the following ones are worth to be reported:

• loss of flexibility with respect to the current open loop vectors technique
• conditioned applicability in certain circumstances (i.e. bad weather conditions impairing the use of both triangles and point merges), that entails the need for radar vectoring to continue to be applied
• concurrent application of radar vectoring and PMS method in case of traffic not 100% PRNAV equipped
• impact on the controllers workload in E-TMA sectors

The controllers involved in the study tended to accept these drawbacks as tolerable side effects of the PMS technique. They were conscious of these limitations, but did not consider them as limitative as to impair the operability of the technique itself and/or its effectiveness. The management of non nominal events (such as bad weather) confirmed these results.

Not analogous results have been achieved on the operability of AMAN and AMAN/PMS. As already mentioned, in theory they tended to associate a good level of operability to these tools/ methods. Unfortunately their actual use during the RTS1 did not allow them to confirm this expectation. Some problems were in fact identified at the operational concept level which conditioned the operability of the tools/methods themselves.

Suggestions are provided in the RTS1 report to solve the problems detected in both AMAN and AMAN/PMS configurations in order to increase their operability. The controllers’ opinion in fact is that the poor results achieved largely depend on the choices made during the RTS preparation, concerning the customisation of the AMAN tool to the specific domain of Rome TMA and the interoperability between AMAN and PMS.

The first aspect is particularly worth of attention. During the study it was in fact evident that AMAN tends to be a domain specific tool. Though the operational concept is generic and in principle suitable to all the domains, actually its adoption in a specific operational reality requires a large effort of customisation to the domain. The refinement of the concepts and of the tools is expected to imply better results in terms of operability.

Concerning the aspects of flight efficiency the results achieved are partially in line with those referring to the operability. In respect to this topic the most positive results were achieved in AMAN/PMS and PMS configurations. In these organisations the traffic was maintained at their optimal flight levels (corresponding to the cruise levels) for the most of time. The same behaviour is not observable in baseline or in the AMAN organisation where the traffic tended to descend earlier, with evident effects in terms of optimisation of the vertical profiles and efficiency. Probably the single benefits of AMAN and PMS blend themselves in AMAN/PMS organisation determining the best conditions.

The same trend was detected in the analysis of the effects of the new tools/methods on capacity. Also in this case in fact the most positive results were achieved in the AMAN/PMS configuration. In this configuration the best exploitation of the runways capacity was registered.

Some interesting insights were also collected on the effect that the new tools/methods may produce on the safety of the operations.

In addition to these results, positive feedback was also collected on the way the RTS1 was organised and carried out. All the controllers involved in the study were very keen in participating and tended to give positive opinions on the appropriateness of the way the study had been arranged. In the light of these results and of the results concerning the impact of the new tools/ methods on the operations of inbound traffic management, a way forward for the RTS2 was also produced.

Traffic trajectories and vertical profiles recorded during the TMA 2010+ Project South RTS1 in AMAN/PMS organisation

Related Materials