Air Traffic Management Concept Baseline Definition - The Boeing ...

arbitrating wherever intents conflict. The intent information then becomes a constraint to
which each pilot and the controller attempt to conform. Controllers that talk of ‘having
the picture’ are referring to knowing not only both the current status and intent, but also
of having a plan for the future. They are fully aware of the situation.
The controller’s intent currently tends to exist only in the head of the controller. Groundbased
decision support systems need to have knowledge of the controller’s intent in order
to support the execution of the ‘tactical plan’. These issues are made more difficult to
resolve within the terminal and tower domains by the nature of the operations in those
domains. Terminal and tower are very time-critical and tend to have both a high
mechanical task loading as well as a high cognitive loading. This places extreme demands
on decision support systems for the terminal environment both in terms of task loading
and situational awareness.
Thus there are major issues surrounding the requirements for a better understanding of
registering intent:
• How to get intent into the system
• How to ensure its validity
• How to update it or declare it invalid
There is another set of issues surrounding the possibility of using some decision support
system to create its own plan, thus resolving human input problems. The main issue in this
approach is how to inform the operator about the system’s plan, (especially if the human is
the back-up system).
Decision support systems will have limited effect unless they have knowledge of both the
pilots’ and controller’s intentions. It is the sharing of intention and then the formulation of
a plan that are key elements in achieving greater throughput whilst maintaining or
improving safety.
4.3.3 Using Structure To Maximize Throughput
The usual response of controllers, when the demand for throughput increases, is to impose
some structure as to how traffic flows through their domain of responsibility. This has
been raised as a possible strategy for maximizing throughput in Section 3.4.7. The
imposition of various restrictions, in a structured form, is an attempt to control the
complexity which results from having many pilots each with different requirements. As
traffic load increases, the controller tends to move from a mode of processing individual
requests to one of restricting individual aircraft so that they fit into a certain structure.
A number of options are available:
1. The structure can be predetermined and accessible to the pilots for planning; e.g.,
Airways, SID’s, STAR’s, or
2. It can be predetermined but not available to the pilots; e.g., letters of agreement
between air traffic control facilities on the use of flight levels or routes, or
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