This paper reports on a series of small-scale experiments conducted with air traffic controllers. The objective was to assess benefits and limits of a method to integrate aircraft flows in the terminal area. The principle is to achieve the aircraft sequence on a point (with conventional direct-to instructions) using predefined legs at iso-distance to this point for path shortening or stretching. Open loop radar vectors (heading instructions) were no longer used and aircraft remained on lateral navigation mode. The method was found feasible, comfortable, safe and accurate although less flexible than today. Predictability was increased, workload and communications were reduced. The inter-aircraft spacing on final was as accurate as today, while descent profiles were improved. The flow of traffic was more orderly with a contained and predefined dispersion of trajectories. All these elements should contribute to improving safety.
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