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An enabling and transformational component of the FAA’s Next Generation Air Transportation System (NextGen) and Single European Sky ATM Research (SESAR); critical to achieving a performance-based NAS. This will provide comprehensive data connectivity, including ground automation message generation and receipt, message routing and transmission, and aircraft avionics requirements.

Will automate repetitive tasks, supplement voice communications with less workload-intensive data communications, and enable ground systems to use real-time aircraft data to improve traffic management efficiency.

Once implemented, Data Comm and NextGen will enable air traffic control to issue complex clearances to a pilot and the aircraft’s flight management system via electronic data transfer instead of time-consuming voice transmission.

Operations and services enabled by Data Comm allow air traffic controllers to manage more traffic, increasing the capacity of the NAS, airspace user efficiency, and enhancing safety.

Lowers operational costs for airspace users and the FAA.

Historical perspective: Controller-pilot communication was and is mainly enabled by radio transmissions on a single shared frequency.

Data communication between aircraft and ANSP is used to exchange clearances, amendments, and requests. At specified airports, data communications is the principal means of communication between ANSP and equipped aircraft. “Terminal automation provides the ability to transmit automated terminal information, departure clearances and amendments, and taxi route instructions via data communications, including hold-short instructions. The taxi route instruction data communication function reduces requests for progressive taxi instructions. Benefits arising from this capability, in conjunction with other NAS investments, include enhanced airport throughput, controller efficiency, enhanced safety, as well as reduced fuel burn and emissions. OI 104207 Enhanced Surface Operations

Potential hazard

  1. NextGen/SESAR hazard condition: Clearances are issued via data link where possible. Associated human performance hazards:
  2. Controller fails to issue clearance to pilot.
  3. Controller issues clearance to incorrect pilot
  4. Voice-issued amendment not entered into automation
  5. NextGen/SESAR hazard condition: Controller sends clearance via DataComm. Associated human performance hazard: Controller fails to execute sending of clearance.
  6. When approach and landing clearances are transmitted by data link to cockpit during this critical phase of flight, traffic watch (“heads-up”) time may be reduced due to the fact that one pilot may be head down responding to and accepting DataComm clearance; especially below 10,000 ft. AGL.
  7. Voice inflection, emphasis, and urgency will be absent in a text-based data communications system.
  8. Loss of “party line” insight to clearance being provided to other aircraft. Spatial information on other aircraft locations provided on NAV displays does not replace intent information provided by listening to clearances provided to other aircraft.
  9. Reliability and security of the CPDLC links may be compromised by cyber security vulnerabilities.
  10. DataLink Challenges from Nav Canada:
  11. Consistency of Information
  12. Hyphen in tail numbers, not in Flight Plan
  13. Leading zeros in AFN name
  14. Different variations of equipment.
  15. Use of adaptation to deal with differences in Avionics, unsolicited Clearances, different clearance formats.
  16. Errors or delays in message flows
  17. Errors in Flight Plan messages causing delay of flight entry in ATC systems , causes issues in order of message and protocols in PDC, FANS and OCL
  18. Missing or delayed AFN, RCLs causing issues
  19. Standardizing Data link information on flight plans
  20. Awaiting ICAO Flight Plan 2012 changes.
  21. System Failures – Complete
  22. Fallback Infrastructure
  23. Degraded Mode of Operations – Partial Loss
  24. Adequate today?
  25. 90% of problems are due to special cases:
  26. Logon problems, hyphens, leading zeros missing CRCs

Corroborating sources and comments

2014 – Meteorological information provided in a digital manner

Building on existing national capabilities, the “new generation” of services will aim to improve efficiency by providing the following:

Consistent meteorological (MET) information regarding location, time and user application to reduce the risk of conflict and to enhance ATM predictability

Common and harmonized MET information

MET information based on the latest science and enhanced observation and forecasting capabilities

MET information integrating forecast uncertainty to aid the determination of uncertainty and risk and serve ATM decision making

Interoperable MET information within the European ATM system via SWIM (sharing data between airlines, navigation services and airport operators)

Integrated MET information into ATM decision making

Sawyer, Michael, Ph.D., Berry, Katie, Ph.D., Blanding, Ryan, NextGen Human Hazard Assessment Report, TASC, Inc., Washington, DC, November 2010

Hazard Log from Results of Phase 4 – Analysis of ConOps2011 Air Traffic Control Concept during 3 workshops in 2006 by Eurocontrol & FAST:

Where are we today – ANSPs, Chris Mouland, General Manager, Gander FIR, Nav Canada,d.b2U (NavCanada actually implemented their CPDLC plan! Results have generally been positive for reducing errors and miscommunications between pilot and controller.)

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