Staggered threshold approach could boost airport capacity

2 August 2019 (Last Updated August 2nd, 2019 12:47)

Busy airports could increase their capacity by around 10% by implementing staggered threshold approach procedures and other new tools.

Busy airports could increase their capacity by around 10% by implementing staggered threshold approach procedures and other new tools.

The European Organisation for the Safety of Air Navigation (Eurocontrol) and Single European Sky ATM Research (SESAR) recently authenticated two new concepts based on Paris Charles de Gaulle Airport scenarios that are aimed at improving runway capacity and managing aircraft noise.

Known as ‘static pairwise separation for departures’, the first concept helps to deal with increasing departure traffic with optimised wake turbulence separation minima and improved separation delivery.

The second concept, dual-threshold, focuses on landing aircraft on closely-spaced dependent parallel runways using staggered thresholds to help reduce wake separation minima and increase production.

For aircraft landing on parallel runways with staggered thresholds, a decrease of the wake separation minima can be achieved by leveraging the height difference between the glideslopes.

Under this approach, heavy and super-heavy aircraft are assigned to the lower glideslope on the runway operated in mixed mode with departures.

With the staggered threshold, medium and light aircraft are allocated the upper glideslope on the adjacent parallel runway, helping them to avoid the wakes generated by heavy aircraft.

Tower controllers also use an optimised runway delivery (ORD) tool to manage the complex pairwise arrival separations. The ORD displays separation indicators on final approach segments.

The staggered threshold approach means the aircraft noise footprint can be moved closer to the airport area for aircraft flying on the upper glide, reducing noise impact on the population in the approach area.

This approach will also help reduce separation minima for some aircraft pairs, offering an increase in capacity throughput of up to 10%.

For departures, air traffic controllers leverage a dynamic departure indicator (DDI) tool to manage departure separations and applicable spacing constraints between outbound traffic in the terminal control area (TMA).

The tool calculates distance and time-spacing indicators and helps the tower controller to provide the required time or distance spacing between departing aircraft.

Based on aircraft performance models of speed and climb profiles, the DDI tool is calibrated on radar and Mode-S tracks, developed with machine-learning techniques.

Outcomes of the departure validation indicate that air traffic controllers using the decision support tool were able to safely reduce the time between departures.

The partners said that further work will be carried out to establish these concepts to support the development of safety, requirement, and guidance material for inclusion in the Eurocontrol runway throughput package by 2022.