Trajectory Specification for High-Capacity Air Traffic Control

In the current air traffic management system, the fundamental limitation on airspace capacity is the cognitive ability of human air traffic controllers to maintain safe separation with high reliability. The doubling or tripling of airspace capacity that will be needed over the next couple of decades will require that tactical separation be at least partially automated. Standardized conflict free four dimensional trajectory assignment will be needed to accomplish that objective. A trajectory specification format based on the Extensible Markup Language is proposed for that purpose. This format can be used to downlink a trajectory request, which can then be checked on the ground for conflicts and approved or modified, if necessary, then uplinked as the assigned trajectory. The horizontal path is specified as a series of geodetic waypoints connected by turns of specified radius. Vertical profiles for climb and descent are specified as low order polynomial functions of along-track position, which is itself specified as a function of time. Flight technical error tolerances in the along-track, cross-track, and vertical axes define a bounding space around the reference trajectory, and conformance will guarantee the required separation for a period of time known as the conflict time horizon. An important safety benefit of this regimen is that the traffic will be able to fly free of conflicts for at least several minutes even if all ground systems and the entire communication infrastructure fail. Periodic updates inn the along-track axis will adjust for errors in the predicted along-track winds.

• Corporate Authors:

  Ames Research Center

  National Aeronautics and Space Administration
  Moffett Field, CA  United States  94035
• Authors:
  • Paielli, R A
• Publication Date: 2004-9-22

Language

• English

Media Info

• Media Type: Print
• Pagination: 30p

Subject/Index Terms

• TRT Terms: Air traffic control; Aircraft separation; Airspace (Aeronautics); Capacity restraint; Climbing flight; Cognition; Human factors; Specifications; Trajectory control
• Uncontrolled Terms: High capacity; Safety benefits; Vertical profile
• Subject Areas: Aviation; Operations and Traffic Management; Safety and Human Factors;

Filing Info

• Accession Number: 01004363
• Record Type: Publication
• Report/Paper Numbers: NASA/TM-2004-212825, A-0412440
• Files: TRIS
• Created Date: Sep 30 2005 8:12AM