The document describes the COMPASS Early Safety Warning System (ESWS) which analyzes flight plans and other data to provide early warnings about potential safety issues to air traffic controllers. The ESWS allows users to visualize flight data on a map and detect conflicts. It also allows users to define custom patterns to identify complex events that could compromise safety. Matches to these patterns are then displayed to users.

1. COMPASS Early Safety
Warning System (ESWS)
SESAR/JU WP-E COMPASS Project
http://www.compass-sesarju.eu
Dimitris Kolovos, Richard Paige
Department of Computer Science
University of York
{dimitris.kolovos, richard.paige}@york.ac.uk

2. Usage Scenario
• ESWS has access to flight plans of flights crossing a
particular sector on a particular day (from 00:00 to
24:00)
• ESWS also has access to other sources of information
such as ACC headers, meteorological data etc.
• ESWS analyses this data and provides early safety
warnings to the user
– Based on user-defined patterns expressed using a
dedicated pattern language (EPL)
• Early Safety Warnings are warnings about complex
events which, if left to develop, can compromise the
safe operation of the ATM system

3. Slide 3
Slide bar allowing the user
to move to different times
in the day.
Map that provides
a visual overview of the
sector.

4. Slide 4
Blue points: Sector entry/exit points
Green points: Waypoints in the sector
Solid lines: Airway fragments
Dashed lines: Ends do not belong to the
same airway but 1 or more flights have
been found to fly directly between their ends

5. Slide 5
Airway fragments highlighted according to
directionality,
Blue fragments: Unidirectional
Red fragments: Bidirectional

6. Slide 6
Selecting en element on the map
makes its properties appear
in the Properties panel

7. Slide 7
User moved time slider to 09:36:00
The positions of flights that have crossed
or will cross the sector are displayed on the map.

8. Slide 8
Selecting a flight makes
its properties appear in
the Properties view

9. Slide 9
The Traffic Level view displays
the number of flights in the sector
at each time during the day.

10. Slide 10
The Fragments view
displays the number of flights
that will be crossing each
fragment during the day.
Double-clicking on a
fragment reveals its ends
on the map

11. Slide 11
The Fragments view
displays the number of flights
that will be crossing each
important point during the day.

12. Slide 12
The Airspaces view
allows users to switch
between airspaces (sectors)

13. Slide 13
We switch to the
EHAMTA sector

14. Slide 14
The conflicts view displays
the results of conflict analysis

15. Slide 15
Double-clicking on a conflict
loads a detail report of the
conflict and highlights the involved
flights on the map.

16. Slide 16
In the report, users can
interact with the evolution
of the conflict in time

17. Slide 17
Users can also explore
other conflicts that are
happening at the same time

18. Slide 18

19. Slide 19

20. Slide 20
Finally, users can also
explore other conflicts which
are not happening at the
same time but which involve
the same flights

21. Slide 21

22. Slide 22
Users can specify arbitrary
patterns using the
Epsilon Pattern Language

23. Slide 23
This pattern checks for flights with
similar call signs (common source of confusion)
This pattern checks for conflicts that
occur at the same time (challenging to handle)

24. Slide 24
This pattern checks for conflicts that
happen while the occupancy of the
sector is particularly high
This pattern checks for conflicts that
involve ascending/descending flights

25. Slide 25
This pattern checks for periods in
the day with low visibility and strong winds

26. Slide 26
Patterns can be matched
against the state of the sector
over the 24hrs period

27. Slide 27
The user can explore identified
matches through a dedicated view

28. Slide 28
Pattern matches are also grouped
by the elements of the airspace that
are involved in them to support
root cause analysis