Data Communications Program

1. Data Communications Program U.S. Implementation Strategy for Data Link Initiation Capability (DLIC) September 28, 2010 SC-214, Bellevue WA Datacomm Program System Engineering Team

2. Background • Working for last year • Current working plan is for Single Data Authority for U.S. domestic en route...but briefing applies regardless • U.S. Plans two phases within Segment 1 • Phase 1 – FANS only in the Tower environment • Phase 2 – FANS and ATN, Tower and En Route

3. Background • Why so complex? • Must handle: • FANS (Boeing and Airbus) and ATN • Airborne aircraft and (multiple) proposed FPs • Possibility of duplicate tails • Multiple services in a logon • Multiple logons from a given aircraft • Frequent discussions have been needed to understand the existing implementations and standards (words and intent), as well as standards still under development

4. Briefing Goals and Intent • Explain the U.S. implementation • Identify any issues with this implementation • Support the development/refinement of the standards • Open discussion to learn from other implementation strategies • Get through one more slide

5. Briefing Topics • Ground Facility Designations (Addresses) • Single Logon Per Flight Leg in U.S. Domestic FIR • Handling of Subsequent Logons • Detecting Duplicate Tail (24-bit or AC Registration) • Required Filing of 24-Bit Address and AC Reg • Version Numbers • Separating Logon Acceptance from Correlation

6. Ground Facility Designations (Addresses) ?

7. Single Logon per Flight Leg in U.S. Domestic FIR • Ground logon will be used for the Tower session as well as the en route session • Goal is to expand that to Oceanic and International • Must still handle subsequent logon • Subsequent logons supercede prior logons completely (Meaning and implications on next slide)

8. Requested services must be “restated” A FANS logon will terminate an ATN session and vice versa Data in the subsequent logon may result in the termination of an existing session, e.g. a change in departure point Subsequent Logon REPLACES prior logon ?

9. Duplicate Tail Condition • Defined as two aircraft that have the same 24-bit address or a/c registration • Shouldn’t happen, but is possible • Detecting this situation the highest priority for the U.S. • Presents a safety hazard if you cannot be sure that the ground is communicating with the correct aircraft

10. Duplicate Tail Condition • 2 Cases • Possible • Example: Previous ATN logon correlated with active flight and new logon received with a different departure point • Subsequent logon rejected - existing session maintained • Probable • Example: Existing session and a new logon received with a different callsign • Logon rejected, existing session terminated, existing logon closed, REG or 24-bit address added to blocked list. ?

11. Aircraft Registration, 24-bit Aircraft Addresses • U.S. will require the filing of both in Field 18 of the ICAO flight plan • Standardization • Provide intent to use CPDLC • Only required fields used for correlation ?

12. Version Numbers • U.S. will support multiple versions within the same ARTCC • Single version of FANS expected in Segment 1 time frame (pre-2020) • Multiple versions of ATN anticipated (examples below) • New SC-214 ATN standard early work package(s)–non-integrated • New SC-214 ATN standard early work package(s) – integrated • New SC-214 ATN standard with advanced capabilities, e.g. 4-D TRAD ?

13. Version Numbers • Support of Backwards Compatibility DLIC-IR 3 When the ATSU System supports the ED-110B/DO-280B Backwards Compatibility option, it shall indicate this to the aircraft by including in the CM-logon response two groundOnlyInitiatedApplications elements associated with CPDLC and referring to version 1 and version 2. DLIC-IR 4 When the Aircraft System supports the ED-110B/DO-280B Backwards Compatibility option, it shall indicate this to the ground system by including in the CM-logon request two groundOnlyInitiatedApplications elements associated with CPDLC and referring to version 1 and version 2. ?

14. Separating Logon Acceptance from DC Correlation • Logon accepted if deemed “valid” • No existing CPDLC session • Contains all required fields • Aircraft not on the blocked list • Contains a supported version • Existing CPDLC session • Above two checks and, • Logon is to same domain as the session • The data does not indicate a possible or probable duplicate tail • Correlation will be attempted ?

15. Separating Logon Acceptance from DC Correlation Backup Slides

16. Additional Topics for Discussion • No call sign change with an existing session • SPR change to clarify that correlation is only required on the initial session establishment (i.e. not required for NDA session establishment) • Including the position in the ATN logon • Proposed changes to message set • New Hold Message • Definition of a position (e.g. distance and direction from a fix) + FRD • Proposed FANS accommodations

17. Additional FANS Accomodation

18. Additional FANS Accomodation

19. UM306 Proposed Change • Current - HOLD [direction] ON [inbound radial] RADIAL / [airway] [direction] TURNS [leg type] LEGS. • Proposed- HOLD [direction] ON [holding track] TURNS [leg type] LEGS. [holding track] radial [0] radialValue airway [1] Airway