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. A series of small scale experiments was conducted with air traffic controllers to assess benefits and limits of the method. The method was found comfortable, safe and accurate, even under high traffic load, although less flexible than today with heading instructions. Predictability was increased, workload and communications were reduced. Even under high traffic load, the inter-aircraft spacing on final was as accurate as today (runway throughput maintained), while descent profiles were improved (continuous descent from flight level 100). As heading instructions were no longer used, aircraft remained on lateral navigation. The flow of traffic was more orderly with a contained and predefined dispersion of trajectories. All these elements should contribute to improving safety.
Merging arrival flows without heading instructions
This paper presents a method to merge arrival flows of aircraft without using heading instructions.