With the steady increase in air traffic, civil aviation
authorities are under continuous pressure to increase
aircraft handling capacity. One potential approach is to
reduce the separation distance between aircraft at takeoff
and landing witliout compromising safety. ATC-Wake
aims to develop and build an integrated system for ATC
(Air Traffic Control) that would allow variable aircraft
separation distances, as opposed to the fixed distances
presently applied at airports. The ATC-Wake project has
developed and built an integrated ATC Wake Vortex Safety
and Capacity platform. A variety of subsystems is integrated
and used within a test bed role:
- To evaluate the interoperability of ATC-Wake with
existing ATC systems currently used at various European
airports;
- To assess the safety and capacity improvements that
can be obtained by local installation of the ATC-Wake
system at various European airports;
- To evaluate operational usability and acceptability of the
ATC-Wake system;
The ATC-Wake system is used in the planning phase
where weather and wake vortex forecast information are
used together with aircraft separation rules to establish
the arrival and/or departure sequence. For approaches, the
aim is to manage separation distances down to 2.5 nautical
miles, in favorable weather conditions, for all aircraft types
regardless of size. For departures, the aim is to reduce the
time separation between departing aircraft to 90 seconds
(in favorable wind conditions). Weather nowcasting and
wake vortex prediction and detection information is used
in the tactical phase to monitor and control safe separation.
Wind forecast data is used to determine time frames
suitable for reduced separation. Criteria on crosswind and
associated safe separation minima are derived from safety
assessment results obtained with the NLR WAke Vortex
Induced Risk assessment (WAVIR) methodology. As
main conclusion the ATC-Wake technical and operational
feasibility analyses and the safety and capacity studies have
built sufficient confidence in the operational concept and
system design for the application of reduced separations to
represent a sound evolution from existing ATC procedures
and working practices, to deliver significant benefits for
runway throughput and average delay per flight without
major rework to the current ATC systems,while maintaining
safety. The next step will be to complete the validation
through production of a Safety Case, Human Factors Case,
Business Case, and a Technology Case towards installation
of the ATC-Wake at one or more European airports. The
best would be to continue with airport shadow mode field
trials, i.e., with direct involvement of airports and air traffic
control centers.