Section 6. Trajectory-Based Operations (TBO)
Trajectory-based operations (TBO) is an air traffic management (ATM) method for strategically planning, and managing flights throughout the operation by using time-based management (TBM), information exchanged between air and ground systems, and the aircraft's ability to fly trajectories in time and space. Aircraft trajectory is defined in four dimensions—latitude, longitude, altitude, and time.
TBO will increase airspace and airport throughput, flight efficiency, flexibility and predictability through TBM, PBN procedures, and increased collaboration with NAS users regarding preferred trajectories and priorities. TBM operations include, but are not limited to, arrival metering, surface metering, terminal metering, and departure scheduling.
TBO objectives must be prioritized when developing and executing the traffic management mission. TBO objectives include continuous and collaborative strategic planning, use of TBM, and use of PBN procedures when possible.
TBM is a methodology for managing the flow of air traffic through the assignment of crossing times at specific points along an aircraft's trajectory. TBM applies time to mitigate demand/capacity imbalances while enhancing efficiency and predictability of the NAS. TBM techniques/tools will be used even during periods when demand does not exceed capacity. This sustains operational predictability and regional/national strategic plan. TBM utilizes capabilities within TFMS, TBFM, and TFDM designed to achieve a specified interval between aircraft.
To maintain the integrity of the air traffic system, facility TM personnel must prioritize TBM when evaluating traffic flow management options.
- Time-based flow management (TBFM). (See Chapter 18, Section 25, Time-Based Flow Management (TBFM).)
- Traffic flow management system (TFMS) programs.
- Ground delay programs. (See Chapter 18, Section 10, Ground Delay Programs.)
- Airspace flow programs. (See Chapter 18, Section 11, Airspace Flow Programs (AFP).)
- Collaborative trajectory options program (CTOP). (See Chapter 18, Section 12, Collaborative Trajectory Options Program (CTOP).)
- Terminal flight data manager (TFDM). (See Terminal Flight Data Manager (TFDM) Order JO 7210.637.)
The above list is not all-inclusive and does not preclude the innovation and application of other procedures that will result in improved customer service.
The efficiency of the NAS is enhanced when all participants have access to the same data. Utilization of shared technology, e.g., TBFM data, trajectory options set (TOS), TFDM data, Flow Constrained Area (FCA)/Flow Evaluation Area (FEA) enhances the coordination process and is critical to the success of trajectory-based operations (TBO).
The ATCSCC is the approval authority for all interfacility TBM operations. While each facility retains authority for the implementation of TBM operations in its airspace, the ATCSCC will be the final authority on how those operations are carried out and the priorities they are assigned in order to best support the objectives and overall efficiency of the NAS.
- Evaluate capacity, demand, and efficiency of the operation. The assessment must include the evaluation of sufficient data required to make an informed decision. The data may include load graphs from TBFM, Flow Evaluation Areas (FEA)/Flow Constrained Areas (FCA), traffic counts and lists from the traffic flow management system (TFMS).
- When interfacility TBM operations are appropriate, coordinate with the ATCSCC and provide the following information:
- A detailed and specific identification of the operation.
- Identification of potential system impacts.
- Advise facilities of potential system impacts. The impacts will be determined by conferencing with impacted facilities, as necessary, and may require sharing FEAs/FCAs, traffic counts and lists from the traffic flow management system (TFMS), or TBFM information. If a TBM operation is modified while on the conference, the ATCSCC will request the facility to modify the NTML entry.
- Issue advisories, as appropriate.
- Monitor TBM operations pertinent to the position of operation.
- Maintain a database of TBM operations for historical and statistical analysis.
- Coordinate TBM with all impacted facilities within their jurisdiction.
- Contact the ATCSCC at any time TBM may result in reportable delays, have an adverse effect on other national initiatives, or result in the implementation of additional initiatives.
- Enter all applicable information in the NTML.