|
The air traffic management system is, by necessity and evolution, a human-centered
system. Humans in the system make the decisions. They, in turn, are supported
by decision support systems (DSS) that aid humans by producing and displaying
the right information at the right time. DSS capabilities have a direct
impact on the number of aircraft a controller can handle, and, consequently,
the number of aircraft the NAS can accommodate. In addition, DSS capabilities
have a direct impact on the amount of flexibility accommodated in the
way airspace users want to conduct their flights.
DSS Tools are not new in the NAS. The current NAS relies heavily on controller
displays of information such as aircraft position and intent, weather,
preferred paths, etc. Rudimentary problem detection logic (like Conflict
Alert and Minimum Safe Altitude Warning) alerts the controller when it
appears an aircraft will violate separation with another aircraft or with
terrain or obstacles. These systems have stood the test of time in that
they have aided in pushing the NAS to be the safest system in the world.
 
DSS capabilities are needed at the very least to handle the
communications and information sharing requirements, and above that, also
for information processing to detect problems (with digital diligence)
and aid in the definition and evaluation of consensus driven, shared solutions.
The evolution of DSS capabilities is a major component of the FAA's
strategy for NAS modernization. It is important to understand that
the capabilities of decision support systems are driven by the evolution
of individual aircraft capabilities and the levels of traffic. When implemented
and taken advantage of, DSS capabilities will encourage further evolutions
of capabilities, in the cockpit as well as on the ground. One can foresee,
then, a spiral of development ahead that will be necessary to accommodate
the evolution of aircraft and traffic structures, even though the exact
capabilities of new DSS Goals cannot yet be determined.
MITRE/CAASD is aiding in the research and development
of DSS tools for the FAA. We have extensive "corporate knowledge" of what
has been tried and how acceptable to the end user such new capabilities
are. There are several examples.
During the timeframe between 1976 - 1990, the FAA sponsored at MITRE
a research program called AERA, short for Automated En Route Air Traffic
Control. With a tight interaction with a team of air traffic controllers,
MITRE engineers evolved a set of controller decision support capabilities,
and built them in MITRE's ATC research laboratories. From this research
has emanated for production and installation a whole set of DSS tools
not only for en route controllers, but also for traffic flow management
personnel.
 CAASD-developed DSS Tools for the en route controller are being implemented
under the FAA's Free Flight Phase 1 and Free Flight Phase 2 programs.
The User Request Evaluation Tool (URET) will enable
the controller to handle more traffic where aircraft are equipped with
traditional or enhanced cockpit avionics, and more complex traffic flows.
The URET technology was transferred
to Lockheed
Martin, the FAA's contractor for the development of new en route systems,
as part of the FAA's Free
Flight Phase 1 program. It is now running as an operational prototype
at the Indianapolis and Memphis Centers; these installations will be replaced
by the production version-and five more centers will be equipped-by the
end of 2002.
The future of  URET
capabilities is bright. In-field evaluations are proceeding now on a strategic
conflict resolution capability, PARR (Problem Analysis Resolution and Ranking). This capability will understand the many
factors necessary to construct candidate resolution maneuvers, maneuvers
that resolve a conflict detected by the conflict probe. URET will then
display all such candidates to the controller to aid in his or her decision
on what to do about this situation. URET conflict resolution will be sensitive
to the type of navigation onboard the aircraft, and try to propose resolutions
that are as efficient as possible. The list of available resolutions will
be presented to the controller in a list ranked by the ability to resolve
the conflict, not introduce new conflicts, and maneuver the aircraft away
from the pilot-requested flight path as little as possible.
The URET DSS capabilities prepare the controller for handling more traffic,
with aircraft of differing capabilities. Combined with other needed enhancements
(e.g., airspace and procedures), they are powerful enablers of the Free
Flight concept. MITRE/CAASD is currently working with Lockheed Martin to move
the production version of URET capabilities quickly to the field; the first
implementation was achieved in Kansas City in December 2001. Already,
the URET DSS Tools (as a fielded prototype in Indianapolis and Memphis,
as a production system in Kansas City) are producing benefits in the shape
more direct routings allowed and fewer in-place traffic flow restrictions;
see the monthly
tabulation of accumulated benefits.
 Another set of DSS tools emanating from the AERA research supports the
decision making done by traffic flow managers. Traffic flow management
is the process of allocating the scarce resources of the NAS to the demand
for those resources. Previously, there were very few decision support
tools for TFM. This changes with the advent of the Collaborative Routing
Coordination Tools, or CRCT.
CRCT is a set of decision DSS capabilities that help in the detection,
diagnosis, and solution of traffic flow management problems. It monitors
the traffic situation in all the sectors of a given center, and alerts
supervisory personnel and TFM decision makers when traffic levels exceed
sector-specific ceilings. When traffic flow problems are detected, CRCT
provides the communication capabilities for solving these problems collaboratively
with other TFM specialists in other facilities and at the Air Traffic
Control System Command Center (ATCSCC) in Herndon, Virginia. CRCT has
been crafted with a "what-if" capability to test proposed resolutions
to traffic flow problems before they are adopted. This allows traffic
management specialitsts to gauge the effects of a proposed resolution,
and to identify other proposed resolutions if too expensive.
|
