In the near future, air traffic controllers are expected to adhere to stringent time and position constraints in controlling traffic. For this new task, new decision-support tools are required which include higher levels of automation, whilst letting humans remain to be the ultimate responsible for the safety of operations. In previous research, an advanced human-machine interface was designed and evaluated that allows controllers to manipulate four-dimensional flight plans of each individual aircraft. In this research, a higher level of automation is explored by designing a new interface prototype that enables controllers to manipulate multiple flows of traffic by facilitating interaction with a path-planning algorithm. A first evaluation of this interface, in which five participants were asked to structure a perturbed airspace as they saw fit, showed that the participants were able to influence the algorithm as they desired and were supported by the interface that visualized the inner workings of the algorithm. However, human influence did not improve the solutions in terms of sector robustness and efficiency, as compared the previously designed interface for aircraft. Therefore, improvements and its use case warrant further research.

Future Air Traffic Management is expected to shift towards four dimensional trajectory (4DT) management, requiring new decision support tools for air traffic controllers to meet stringent time and position constraints. In previous work, a prototype human-machine interface has been developed for 4D trajectory manipulations of single aircraft. This paper describes a tool for multi-aircraft manipulation and investigates its potential control efficiency benefits. A human-in-the-loop experiment (N = 13) has been conducted using scenarios with sector disruptions and varying conflict geometry. Results show that participants preferred to use multi-aircraft manipulation for groups of aircraft having small convergence angles. Since the current implementation involves re-routing all selected aircraft through one common waypoint (referred to as a 'merge point'), extra additional track miles were flown and airspace robustness reduces. Regarding efficiency and safety, multi-aircraft trajectory manipulation seems favourable only for smaller convergence angles, although this also depends on the way the operators place the aircraft merging points. For future development, attention should be devoted to making flight efficiency constraints of each aircraft more salient, enabling controllers to better time the rerouting multiple aircraft and more fairly distribute re-routing costs.

The current evolution of the ATM system, led by the SESAR programme in Europe and the NextGen programme in the US, is foreseen to bring a paradigm shift to the work of the air traffic controller. Rather than the current primarily tactical control method, one aims for the introduction of more strategic, 4D (space and time) trajectory management. In both programmes a central role is foreseen for the human operator, aided by higher levels of automation and advanced decision-support tools. Previous work has shown promising results in the design of such automated support tools, however, issues with controller acceptance and intuitiveness were found to be key for their overall acceptability. This paper presents a concept decision-support tool for 4D trajectory management that aims to overcome these issues by directly visualizing action-relevant solution spaces. Rather than imposing a certain control strategy, the solution space visualizes all possible control actions, regardless of their optimality. Results of preliminary validation experiments with partial implementations of the solution space representation demonstrated the viability of the concept, but also highlighted areas for improvement.