Taking trajectory based operations to the next level: Management by trajectory

Management by Trajectory (MBT) is a NASA concept for taking Trajectory Based Operations (TBO) to the next level of maturity. MBT looks beyond enabling technologies to flesh out the operational concept and look at how TBO changes the ways in which actors interact. In MBT, each aircraft has an assigned trajectory that is negotiated between the Federal Aviation Administration (FAA) and airspace user (AU) and complies with all National Airspace System (NAS) constraints. Any deviation from the assigned trajectory must be negotiated. In addition to the request/response interactions between controllers and pilots that have so far been proposed to support Data Comm, trajectory negotiation under MBT leverages emerging capabilities to support much richer negotiations. MBT proposes a higher level language to support new kinds of requests and responses, such as providing new or amended constraints to which a trajectory must conform and allowing the trajectory to be proposed by the AU, or controllers offering solution options to the AU for the AU to select the preferred solution. The key MBT benefit mechanisms are trajectory predictability and AU flexibility. Improved predictability supports more efficient operations, from earlier and less frequent conflict detection and resolution to better calibration of traffic flow management decision-making to balance demand with capacity. Improved flexibility allows AUs to act on their trajectory preferences. This paper provides an overview of the MBT concept and discusses open questions to be explored in future concept evaluation activities.