WP2 Current situation analysis – Aircraft perspective Philippe Louyot (CENA)

1. WP2Current situation analysis – Aircraft perspectivePhilippe Louyot (CENA) CARE/ASAS Action FALBALA Project Dissemination Forum – 8th July 2004

2. WP2 objectives (1/2) • Assessment of the current situation from an aircraft perspective using recorded radar data from: • Frankfurt TMA (DFS) • London TMA (NATS) • Paris TMA (CENA) • En-route European Core Area (EUROCONTROL Maastricht) • Main assumption: all aircraft are ADS-B in-and-out equipped

3. WP2 objectives (2/2) • How a pilot would see the traffic on a CDTI (Cockpit Display of Traffic Information) • Qualitative assessment: • for one selected aircraft of interest, CDTI fed by radar data (replay) • Quantitative assessment: • for a set of aircraft of interest, computation and aggregation of indicators (use of big amount of radar data hours)

4. Aircraft and flight operations of interest • VFR flights • IFR flights during 3 Package I AS applications: • enhanced traffic situational awareness during flight operations (ATSA-AIRB) • enhanced visual separation on approach (ATSA-VSA) • ATSA during enhanced sequencing and merging operations (ATSA during ASPA-S&M)

5. Qualitative assessment

6. Qualitative assessment method All aircraft One aircraft of interest • Selection of one aircraft of interest from radar data • Traffic view from this aircraft of interest thanks to a CDTI

7. CDTI features • The goal is not to design a CDTI, but only to illustrate the issues • Airbus-like ND implementation • Ranges: from 10 up to 320 NM • Filtering: only vertical band filtering (TCAS legacy) • Normal [-2700ft, +2700ft] • Above [-2700ft, +9900ft] • Below [-9900ft, +2700ft] • Automatic count of displayed aircraft (main indicator)

8. CDTI modes • ND modes: Arc and Rose Mode (Plan mode not retained) Plan mode Arc mode Rose mode

9. Qualitative assessment

10. Illustration of ATSA-AIRB in London TMA

11. Illustration of ATSA-AIRB during VSA at Frankfurt airport

12. Illustration of ATSA-AIRB during S&M operation in Paris TMA

13. Qualitative results (1/4) • For an acceptable CDTI legibility, the maximum number of displayed aircraft would have to be limited to about fifteen

14. For VFR flights, a CDTI is likely to improve safety from the additional traffic information Qualitative results (2/4) Example: A VFR flight arriving at Toussus airport will cross another conflicting VFR flight on another radio frequency

15. Qualitative results (3/4) • For IFR flights, it is not obvious to decide which aircraft must be filtered Example: IFR during initial approach at CDG.

16. Qualitative results (4/4) • A safety-oriented filter would be different from a situational awareness oriented filter • Safety: closer aircraft (in time or distance) • ATSA: aircraft inbound to the same runway for example • These aircraft may not be the same particularly in TMA & E-TMA

17. Quantitative assessment

18. Quantitative assessment method • Selection of all the aircraft of interest with their associated period of interest • Computation of the number of displayed aircraft in all display possibilities • Aggregation of this figure over several days

19. Selection of the aircraft of interest (1/3) • VFR flight: selection thanks to mode A code • IFR flight: selection thanks to flight phases recognition • procedure matching for: • STAR • initial approaches • RNAV approaches • radio failure approaches for Radar vectoring • final approaches • altitude based selection for cruise

20. Selection of the aircraft of interest (2/3) • The flight phases used are not exactly the same as the standard ones • Standard flight phases / used flight phases mapping

21. Selection of the aircraft of interest (3/3) ATSA AIRB ATSA during S&M ATSA during VSA

22. Computation of seen aircraft (1/2) • Count of all aircraft in several defined volumes centred on the aircraft of interest • The defined volumes are the combination of: • Rose and Arc mode area (disc and heading related sector ) • range: 10, 20, 40, 80 and 160 NM • altitude band filtering: ALL, NORMAL, ABOVE, BELOW +2700ft -2700ft

23. Computation of seen aircraft (2/2) • Count done for each antenna turn • Radar coverage taken into account

24. Aggregation by position of the aircraft of interest Arc length on given procedure Geographic mosaic Aggregation and presentation STAR: ARC 80NM BELOW (average of displayed traffic)

25. Process overview Procedure XML file Radar data Radar data sorted by turn (all plots) Flight selection (with period of interest) Procedure data for arc length computation

26. Process outcomes • For each phase of flight and each display selection • Average of displayed traffic • Maximum of displayed traffic • Number of measures (traffic density of aircraft of interest) • Synthesis by flightphases

27. Quantitative results (1/3) • No direct link between the airspace density and the density of traffic information Maximum number of displayed traffic (Arc Normal 80NM) Cruising aircraft density

28. Quantitative results (2/3) • There is a lot of difference between average and maximum figures • Average and maximum number of displayed aircraft per phase of flight (Arc mode, Normal)

29. Quantitative results (3/3) • For VFR flights, a simple vertical filtering seems to be sufficient • For IFR flights, need for a specific filtering possibly depending of the phase of flight • The number of displayed aircraft is often too high even with the “Normal” altitude band filtering

30. Airborne surveillance requirements

31. Assessment method • Computation of the maximum number of detected aircraft to help setting up airborne surveillance requirements • Use of Maastricht radar data • Independently from the phase of flight Rose 160NM No vertical filtering

32. Results for airborne surveillance • Maximum number of 340 within a 160NM surveillance range • Extrapolatedmax  0.005 * range2 + 1.2 * range

33. Conclusions & recommendations

34. WP2 conclusions • Initial assessment of traffic information possibly displayed on a CDTI (for VFR & IFR) • Illustrations through typical scenarios • Computation of maximum and average number of traffic • Evaluation of required airborne surveillance performances • Validation of the approach (radar data => current airborne traffic information assessment) • Identified limitations of the approach • Sensitivity of the results to the amount of cumulated data • Results near airports depend on radar coverage quality • Some bias due to aircraft on the ground

35. WP2 recommendations for future work • A better knowledge of the present ND selections in use would be useful in order to reduce the large amount of computed data • Standard deviation computation to complement the maximum and the average assessment • Specific analysis focused on aircraft on the ground could be performed • Use of mosaic should be preferred to the use of arc length

36. Questions & discussion