This paper reports on an experiment conducted with air traffic controllers to investigate the joint use of a sequencing tool and spacing instructions to enhance the management of arrival flows. The experiment simulated two en-route and one approach sectors (total of seven positions). It was shown that sequencing tool and spacing instructions can be jointly used in en-route and in the terminal area, with high benefits particularly in the terminal area. Main benefits are: a positive impact on controller activity (earlier flow integration and relief from late vectoring) and on control effectiveness (more regular inter-aircraft spacing on final approach, a slight increase of throughput and straighter trajectories with no dispersion below 4000ft). Acronyms ADS-B = Automatic Dependant Surveillance-Broadcast AMAN = Arrival Manager (sequencing tool) ASAS = Airborne Separation Assistance System E-TMA = Extended TMA (en-route sectors performing pre-sequencing of arrival flows before transfer to TMA) FAF = Final Approach Fix IAF = Initial Approach Fix TMA = Terminal control area ("approach" control).

This paper reports on small-scale experiments conducted with air traffic controllers. The objective was to investigate non-nominal situations when using airborne spacing in the terminal area. The following situations were considered: mixed equipage, holding patterns and typical unexpected events (go-around, emergency, radio failure, spacing instructions not correctly executed). In applying the airborne spacing procedure for non equipped aircraft, handling mixed equipage was found to be entirely feasible. Initial trends suggest that 50% equipped aircraft already brings some benefits compared to 0% although not as much as with 100%. Receiving aircraft from the holding patterns and then using airborne spacing for final integration was found feasible and comfortable. Recovering from the unexpected events was found less difficult than initially anticipated and was evaluated as similar to today's operations.

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.