Operationalization of Norms in
Aircraft Approach/Departure
Decision Support
Laura Savičienė, Vilnius University
July 9, 2012
Problem statement
• To develop a conception for operationalization of
the aircraft approach/departure norms in a decision
support system, taking into consideration the use of
lidar (laser radar) for aircraft tracking
• Tasks:
1. Modeling norm violation risk in the airport traffic zone
2. Modeling radar and lidar data fusion
3. Development of a prototype decision support system
July 9, 2012
Vilnius University, Faculty of Mathematics and Informatics
Context
• The SKY-Scanner project: using lidar to track
aircraft in the airport traffic zone
– Part of the SKY-Scanner project was the DSS for
the air traffic controller
July 9, 2012
Vilnius University, Faculty of Mathematics and Informatics
Assumptions
• Assumption 1: lidar, used together with the primary
radar, provides aircraft position with a high degree of
accuracy
• Assumption 2: the DSS simply informs the controller,
who takes the decision on actions
July 9, 2012
Vilnius University, Faculty of Mathematics and Informatics
Normative rules in aircraft
approach/departure
• Norms in the following areas are examined:
– Air traffic control (ATC) separation rules: horizontal
sep. (in nautical miles) and vertical sep. (in feet)
– Airport approach/departure procedures: norms are
presented as maps, charts, tables, and textual
descriptions
– Wake turbulence separation rules: time-based
separation
– Rules for avoiding volcanic ash: zones of restricted
operations depending on particle concentration
July 9, 2012
Vilnius University, Faculty of Mathematics and Informatics
Approach/departure procedures
• Each airport has a unique
approach/departure procedures
July 9, 2012
set
of
the
Vilnius University, Faculty of Mathematics and Informatics
Related works
• Current aviation-related systems do not model norms
comprehensively, but there is some research in that direction
• Conflict detection and resolution process structure is adapted to
aircraft separation conflicts, but can be expanded to cover other
normative rules
• Study in real-time decision making suggests to facilitate the
encoding step of the user’s cognitive process, possibly, by
providing more intuitive visualizations
• 2D visualizations in ATC are no longer sufficient, and 3D
visualizations have drawbacks; possible strategy to overcome this
is to augment the 3D screens with auxiliary 2D elements
July 9, 2012
Vilnius University, Faculty of Mathematics and Informatics
Decision support process
July 9, 2012
Vilnius University, Faculty of Mathematics and Informatics
Modeling of norms
• Geometrical norms, i.e. those concerning
aircraft position and speed, are identified
• Norms are modeled from the perspective of
violating them
• Two norm types are identified: limit-based and
deviation-based
• Each norm is modeled with a factor, a pattern,
and a normative value vN
July 9, 2012
Vilnius University, Faculty of Mathematics and Informatics
Modeling of risk
• Each normative rule is represented as a risk definition
in the decision support system
• Risk definition associates the modeled norm with a set
of thresholds and discrete risk levels
• Risk evaluation maps the observed value of the norm
factor to a discrete risk level:
– For L risk levels, L-1 thresholds (or pairs of th.) are needed
– A separate indicator can be created for each norm
July 9, 2012
Vilnius University, Faculty of Mathematics and Informatics
Risk definition example:
indicated airspeed
Norm factor: “indicated airspeed”;
Norm type: “limit”;
Norm patter: “<= vN”;
Expected value: 210 kt.;
Thresholds: v0 = 202 kt., v1 = 206 kt., v2 = 214 kt.;
July 9, 2012
Vilnius University, Faculty of Mathematics and Informatics
Risk definition example:
altitude
Norm factor: “altitude”;
Norm type: “deviation”;
Norm pattern: “= vN”;
Expected value: 3900 ft. at 6 DME (deviation 0);
Thresholds: dn0=-0.5, dp0=2, dn1=-1, dp1=3.5, dn2=-1.5, dp2=5;
July 9, 2012
Vilnius University, Faculty of Mathematics and Informatics
Visualization of the approach
procedure: 2D-in-3D example
July 9, 2012
Vilnius University, Faculty of Mathematics and Informatics
Visualization of the approach
procedure: pure-3D with “rings”
July 9, 2012
Vilnius University, Faculty of Mathematics and Informatics
Results (1)
• A conception for norm operationalization and norm
violation risk model
– Each norm is modeled with a factor, a pattern, and a
normative value vN
– Each norm is represented as a risk definition
– Risk evaluation maps the observed value of the norm factor
to a discrete risk level
– The solution combines well known models (piecewise linear
risk model and traffic light decision making principle)
July 9, 2012
Vilnius University, Faculty of Mathematics and Informatics
Results (2)
• Prototype decision support system
– Demonstrates modeling of several norms
– Adapts advanced visualization ideas
– Provides real-time demonstration of the solution
July 9, 2012
Vilnius University, Faculty of Mathematics and Informatics
Conclusions
• The proposed norm operationalization conception enables
to represent a subset of aircraft approach/departure
normative rules (geometrical norms) in a decision support
system for the air traffic controller
• The prototype decision support system provides an
integrated solution to facilitating the controller: risk
indicators automate detection of possible norm violations,
and
2D-in-3D
visualizations
help
comprehend
conformance to the approach/departure procedure
• Phases, needed to operationalize the norms, are identified,
but the process cannot be fully automated
July 9, 2012
Vilnius University, Faculty of Mathematics and Informatics
Thank You for Your Attention!
July 9, 2012
Vilnius University, Faculty of Mathematics and Informatics