The Dutch Air Traffic Control has implemented fixed approach trajectories within approach control during night operations when traffic density is low. During the day, when traffic density is higher, vector-based operations are used. The Dutch Air Traffic Control aims to implement fixed approach trajectories when traffic density is high. This shift from the current vector-based operations will allow aircraft to perform a continuous descent and fly around inhabited areas, reducing the emissions and noise. To improve the capacity of the landing runway in strong headwind conditions, time-based separation is envisioned. Separating aircraft on time will result in a constant runway capacity in all wind conditions. However, to make these changes possible, additional decision support tools are required to assist controllers and reduce their workload. This paper discusses the use of a new toolset, centered around a time-space diagram which shows the expected arrival time and distance-to-go to a selected reference waypoint. Results of an experiment with eight professional air traffic controllers show that the added tools allowed future conflicts to be solved sooner and with fewer instructions. Aircraft followed the fixed approach trajectories better in the latter stages of the approach when compared to current vector-based operations. Although a slight increase in runway capacity was observed with the new toolset, it was not statistically significant. The workload of the controllers did not show a difference when using the new toolset. In conclusion, the added tools enabled the controllers to combine fixed approach trajectories with time-based separation. However, to reduce perceived workload, future designs should aim to integrate the time-space diagram on the main radar screen such that controllers do not need to switch attention between screens.

Air traffic sector demand and capacity balancing is an important process to enable safe and efficient flight execution. In current operations, demand and capacity are determined based on schedules and flight plans. In reality, disruptions to flights create a different situation that may not have been anticipated by the Air Navigation Service Provider (ANSP). Wrong demand forecasts may cause unnecessary network regulations or inefficient flight execution. This research aims to improve air traffic sector demand forecasting, by exploring machine learning based trajectory prediction. In light of the Trajectory Based Operations (TBO) concept that is being developed within Air Traffic Management (ATM) research, a trajectory-based approach is taken to improve demand forecasts. To achieve this, the transformer neural network was identified as a suitable generative model that can predict aircraft trajectories. Using available traffic messages from the Eurocontrol Business-to-Business (B2B) connection, and actual trajectories obtained from the OpenSky ADS-B repository, a successful transformer neural network was built. This trajectory predictor could accurately generate trajectories, outperforming the flight plan and other neural network approaches by a large margin. For demand prediction, the introduction of improved trajectories provided small gains that could potentially lead to more stable predictions.

With its 500.000 flights per year, Schiphol Airport is one of the busiest airports in Europe. Efficient runway use is vital for a smooth day-to-day operation. This paper investigates the new runway scheduler at Schiphol Airport, also referred to as the Departure Manager (DMAN). The new DMAN is built for a better utilisation of the outbound capacity with a higher predictability. This study aims to verify whether positive behaviour regarding earlier Target Off-Block Time (TOBT) updates leads to the desired results in capacity, predictability and reduced delay, based on historical data. An experimental model was used to simulate a new Departure Manager (DMAN), which uses a set of priority rules to assign flights to the runway slot in which they depart. The simulation did not find an overall significant result for all cases, runways and months, due to the averages influenced by the size of the data. However, a positive trend can be seen in the presented results, indicating that earlier TOBT updates lead to a better runway schedule. One cannot schedule better than on time, but late TOBT updates accumulate like a snowball effect throughout the planning.

At many airports, the arrival and departure demand often outpaces the available airport capacity. Therefore, the flowof arriving and departing aircraft needs to be controlled to ensure safe and efficient operations. Many airports have been implementing systems that provide electronic assistance for air traffic control in planning and sequencing the flow of arriving and departing aircraft. Those systems are called the ArrivalManager and the DepartureManager. At the moment the two systems do not take each other’s traffic situation into account. Arriving and departing aircraft are accepted to enter the same airspace, even though no information exchange exists between the two. The lack in information exchange is not problematic for airports operating independent arrival and departure runways, arriving aircraft paths do not hinder departing aircraft paths. However, for dependent runways, when aircraft arrivals hinder departing aircraft, and vice versa, the lack of information exchange between the two systems, ATC will not be able to fit as many departures into the arrival stream as is planned by the Departure Manager. This can cause severe (surface-) congestion problems at airports that rely on dependent runways. This study focused on the interaction between arriving and departing aircraft for dependent arrival and departure runway combinations and the magnitude of the resulting arrival and departure capacity interference. With this knowledge, this research developed and assessed strategies for coordination between Arrival Management and Departure Management. First, the uncoordinated Arrival and Departure Manager (ADMAN) was developed in BlueSky Open Air Traffic Simulator to represent the current management of arrivals and departures; the AMAN and DMAN schedule inbound and outbound independently from one another. Second, the coordinated ADMAN was developed in BlueSky Open Air Traffic Simulator as well. The coordinated ADMAN includes three different coordination modules between the AMAN and DMAN that aims to increase the operational efficiency of dependent arrival and departure runway combinations. Each of the implemented coordination modules checks the number of departure slots that are available in the scheduled arrival stream and intervene if necessary, taking into account different assumptions. To obtain insight into the future magnitude of arrival and departure capacity interference and to demonstrate the for a coordination mechanism between the management of arrivals and departures, fast-time simulations were performed with the uncoordinated ADMAN. This experiment used an arrival and departure runway combination with amissed approach dependency to assess future arrival and departure capacity interference. To express the severeness of arrival and departure capacity interference, capacity was used as Key Performance Area (KPA). The results showed that if the arrival load would increase, due to RECAT and TBS, the arrival and departure capacity interference worsens. These results demonstrated the need for coordination mechanism between the management of arriving and departing aircraft. A second experiment was set-up to assess the performance of the different coordination modules implemented in the uncoordinated ADMAN. The three coordination modules were evaluated in terms of capacity, delay, coordination module interventions and ATCO workload by performing fast-time simulations. Like the first experiment, the second experiment used an arrival and departure runway combination with a missed approach dependency to test the modules for different levels of arrival load during morning and evening arrival peaks. The results showed that the departure capacity could be increased, and departure delay could be decreased, when the AMAN meters the arriving aircraft as a function of the departure ground situation. As this research set the start for coordinated arrival and departure management for dependent runway operations, other concepts could be developed tomitigate the effect of arrival and departure capacity interference. Furthermore, to improve the realism of both the uncoordinated ADMAN and coordinated ADMAN, it is recommended to upgrade the Air Traffic Control module.

The Compound Annual Growth Rate (CAGR) of the aviation industry is predicted to be 4.1% from 2015 to 2045 [23].In recent years, however, increasing public pressure has been put on the industry to further reduce noise and carbonemissions. This can be done by eliminating all horizontal flight segments during the approach phase, reducing theaverage thrust. Such an approach is called a Continuous Descent Approach (CDA) and has been the subject of manystudies. Ideal CDAs are flown with idle thrust, which results in the largest fuel flow reduction but which has a verybig drawback; The vertical profiles of ideal CDAs vary greatly between aircraft making it difficult for ground-basedsystems to predict the exact position of an aircraft ahead of time ([35]). In order to deal with this added uncertainty,additional separation is needed. This greatly reduces the capacity, which means that such a concept can only beused when there is little traffic. ([26]) This greatly limits the benefits since there is very gain during such times. Thereare other types of CDAs, which take away the need for this added uncertainty, however. These are called a fixed orconstant Flight Path Angle (FPA) approaches. Where the FPA during ideal CDAs is optimised by each aircraft’s FlightManagement System (FMS) for that particular flight, an average is used for this type. This average is then flown witha small, off-idle, amount of thrust. Which means that although in general the noise and emission reductions aredecreased when compared to ideal CDAs, ([35], [8]) the capacity is increased ([25]).In this thesis, fixed-route fixed FPA approach procedureswill be designed for the SchipholTMA and compared to currentdesigns. This will be done by trading off the environmental benefits for capacity under robustness and flexibilityconstraints. Although only part of the descent occurs inside of the TMA, most of the emission and noise reductionscan be achieved here as the inefficient level segments that usually occur here are moved to the upper airspace ([32]).