LINK2000+ European ATS Provider Benefits Real-time Simulation Results

1. LINK2000+ European ATS Provider Benefits Real-time Simulation Results ATN2002 Conference London, 24-25 September 2002 Rod McGregor

2. LINK2000+ Programme • Datalink Implementation forEurope 2002-2007 • Services selected because of identified effective operational benefits • Implementation at centres andairports where the need exists • Affordable infrastructure - ATN over VDL2 (exploiting airline investment)

3. LINK2000+ Real-time Simulation Project • followed other datalink projects such as EATCHIP IIIb/EOLIA and PETAL IIe • concentrated on operational aspectsnot technical aspects of datalink implementation • focused on an early implementationand non-time critical datalink services that had been previously evaluated • explored the implementation of datalink from the controllers perspective • developed acomplex real-time datalink simulator to replicate ATN datalink functionality

4. Simulation Conduct • Conducted at the EUROCONTROLExperimental Centre near Paris • Involved project teams from theAix-en-Provence and Rome ATCCentres, as well as the EEC and the LINK2000+ Programme • A major effort for the EEC with over50 individuals committed to thesystem build and experimental conduct • Used operational controller teams to provide authentic feedback on the use of datalink in future datalink scenarios

5. LINK2000+ Experiment Objectives • Confirm the feasibility of conducting voice and datalink in a mixed-mode environment • Determine good practice when considering datalink over voice (and vice-versa) • Identify potential changes to controller working methods • Identify ATC Procedures required for datalink operations • Assess the safety implications of non-nominal situations • Define the need for improvements to the datalink interface • Assess the operational and technical response times √

6. Real-time Simulation • February 2002, 3weeks including training and measured exercises (28 measured exercises of 1 hour) • 14 Controllers (7 from Aix-en-Provence and 7 from Rome) • Traffic based on busiest regional dayin 2001(plus 10% and 25%) • Airborne datalink equipage at0%, 25% and 50% (representingthe implementation period) • Scenarios1 - Nominal (variation in traffic and datalink equipage)2 - PC Transfer (routine transfer task moved to the PC)3 - ACM Monitor (datalink aircraft did not check on frequency)4 - Non-Nominal (degradation of performance)

7. NW BAW1234 290 350 350 BEKOS h045 m81 r25 • LINK2000+ Controller Interface (Two Controllers per sector each with a 28” screen) • No ‘Paper’ Flight Strips • Interactive Aircraft Label with 3-Button Mouseas sole input device (no keyboard) • Extensive use of colour coding • SYSCO silent electronic co-ordination • Graphical and list display of flight data • Safety Nets and System Reminders • Integrated datalink functionality with messages represented in track labels and Message In/Out windows

8. LINK2000+ Datalink Implementation • DLIC - Datalink Initiation Capability - (between Equipped and Non-Equipped ATC Centres) • ACM - ATC Communication Management - Silent transfer of Data Authority and Aircraft Frequency Change Instructions, with indication that the Aircraft was ‘Monitoring’ the new frequency • AMC - ATC Microphone Check - Via simulated “Stuck Microphone” message to all aircraft • ACL - ATC Clearances – including Cleared Flight Level, Heading, Direct Route, Speed, and Rate of Change

9. LINK2000+ Datalink Implementation • LACKS - Logical Acknowledgements– for all messages (defined timeouts for LACK response, Operational Response and Standby Offset) • Delay Value based on fixed (6 second) delivery time and defined Failure Rates for datalink messages • Pseudo-pilot responses to uplinked messages including WILCO, STANDBY, UNABLE, and scripted downlinks of REQUEST DIRECT and REQUEST LEVEL

10. Datalink Benefits • Real-time Simulation Analysis • Subjective analysis based on: • Simulation Observation • Controller Debriefing Sessions • Questionnaires (Pre-simulation,Exercise, and End of Simulation) • Controller Workload Recordings • Supported by objective analysis based on recorded system data (including time-stamped HMI actions and datalink messages)

11. During the experiment • 1953flight hours recorded for all sectors over the measured exercises • Sector throughput (1 hour) from50 - 108(depending on sector) • Maximum number of aircraft on frequency ranging from 18 - 35aircraft • 424 Pilot datalink requests downlinked to the controllers • 2719Controller instructions uplinked to simulated datalink aircraft

12. Results - Controller comments • The Air/Ground concept was easy to understand • Air/Ground datalink procedureswere easy to work with • Using Air/Ground datalink reducesroutine communication tasks • It was not difficult to decide whento use datalink or voice tocommunicate • It was easy to learn to work with the Air/Ground datalink

13. Results - General • Voice channel occupancy significantly reduced • 0% Datalink (39%) • 25% Equipage - 32% (-18%) • 50% Equipage - 26% (-33%) • Further gains (35%-50%) when combined with datalink aircraft ‘Monitoring’ not calling on frequency

14. Results - Working Method • Controllers took less than 3 weeks to integrate datalink in to a new effective working method • Two separate control techniques developed for Datalink and Non-datalink aircraft (as non time-critical messages could become time-critical) • CPDLC clearances were (apparently) less suited to highly tactical environments (controllers reported two minutes required for action)

15. Results - Task Reallocation • Planning Controller must be active (focussed on the screen) notpassive as today • ACM with PC Transfer withDatalink Aircraft Monitoringwas reportedly very successful • ACL service more complex totransfer clearance tasks to the PCdue to issues of control responsibility, teamwork, and situational awareness

16. Results - Controller Interface • Clear distinction between equipped and non-equipped aircraft essential • Equally efficient HMI inputs for both equipped and non-equipped aircraft required • Revert-to-voice procedure and system update, in case of datalink error (DLError or No Reply) as short as possible • History of datalink messages required to support better team situational awareness

17. Results Time-outs and Response Times • Timeouts for LACK response and No Reply as short as possible (30 seconds and 60 seconds) • Mean controller response time to a pilot request was 40 seconds (including delivery time) • (Pseudo-pilot response time was 25 seconds) • Controller composition times for datalink messages 75% less than 2 seconds and 99.5% less than 10 seconds (EATCHIP III datalink interface) • Non-nominal degraded datalink performance had little impact for controllers (due non-time critical use)

18. Summary - ATS Provider Benefits • Results suggest that a safer, more efficient, ATM system through Datalinkimplementation is achievable • Effective R/T reduction and task re-distributionwas demonstrated “With datalink it should not be a problem if you never talk to an aircraft the whole time it is in your sector” • Next - further interface improvements andmore research into teamwork and situational awareness issues • Finally, datalink was shown to have the potential to revolutionise ATM, perhaps enabling change as radical as the introduction of radar

19. Contacts • Rod McGregor - LINK2000+ RTS Project Manager (EEC) roderick.mcgregor@eurocontrol.int • Alex Wandels – LINK2000+ Programme Manager (Brussels) alex.wandels@eurocontrol.int • Chris Brain – LINK20000+ Operational Issues (Brussels)christopher.brain@eurocontrol.int • Martin Adnams – Implementation Issues (Brussels)martin.adnams@eurocontrol.int • References • LINK2000+ Real-time Simulation Report - September 2002 (EUROCONTROL Experimental Centre Report)