Original Article
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U. Ahlstrom: AIRWOLF Weather Advisory Tool
and 2 o’clock, 15 miles. Precipitation area is 25 miles in diameter.’’ In previous work, we assessed ways to optimize the development of controller weather displays (Ahlstrom, 2005). Optimal weather displays could enhance controllers’ weather situation awareness and assist controllers when relaying important weather information to pilots. However, today’s manual production of weather advisories via radio adds another constraint on controllers during high-workload periods. This further emphasizes the need to explore ways to (a) support the controller with weather advisories and (b) optimize weather-related communication between the controller and the pilot. One way of integrating weather information at the controller workstation is to let the ATC system keep track of weather hazards. Rather than providing controllers with more weather information, the system could use the weather data and automatically track weather hazards and sector traffic and alert the controller of impending conflicts. This could enhance weather avoidance operations even further as there would be no need for controllers to manually correlate weather and traffic data (current ATC operations). In the following section, we describe an automatic weather probe that tracks aircraft and weather hazards and alerts the controller to impending conflicts. In addition, the weather probe automatically generates weather advisories for sector aircraft.
Automatic Identification of Risky Weather Objects in Line of Flight In previous research, we outlined a general weather probe algorithm for air traffic controllers (Ahlstrom & Jaggard, 2010). We named the weather probe concept after its function: Automatic Identification of Risky Weather Objects in Line of Flight (AIRWOLF). The AIRWOLF tool operates by (a) calculating a future aircraft position for an aircraft (e.g., 15 min along the aircraft’s projected route) and then (b) determining whether the route to the future position intersects with a known weather object (e.g., precipitation or convection area). If there is an intersection between an aircraft route and a weather object, the probe will detect it and treat it as a conflict. The probe performs this calculation for all aircraft at their associated altitudes. This is an iterative calculation that the algorithm performs for each aircraft every time there is a flight data update in the system. The AIRWOLF tool checks the aircraft’s flight plan for route information for flat tracking aircraft (i.e., aircraft that conform to their specified routes). If an aircraft is free tracking (i.e., aircraft that are not flying their routes), the probe uses the aircraft’s current heading to perform the future position calculation. The time parameter for the calculation of the future aircraft position can be adjusted to account for different sector needs (i.e., sector size, traffic patterns, and so forth). The AIRWOLF tool can also use a function that is defined by the FAA based on weight that determines whether a particular aircraft is small, large, or heavy. This implies that the tool can be programmed to Aviation Psychology and Applied Human Factors 2015; Vol. 5(1):18–35
Figure 1. The weather conflict alert. probe for one set of weather hazards for small aircraft (e.g., visibility, ceiling, precipitation, convection, icing, and turbulence) and another set of weather hazards for large and heavy aircraft (e.g., heavy and extreme precipitation, severe and extreme turbulence). When the AIRWOLF tool detects a future conflict between an aircraft and a hazardous weather object, it alerts the controller. In our current implementation, the controller was alerted by a weather conflict number in line 0 of the data block. When the tool generates a weather conflict alert, the controller can display the aircraft route and the weather hazard area (see Figure 1). In this paper, we will focus on the probing of WARP data, although the AIRWOLF tool can read and probe any gridded weather data sets.
Automatic Weather Advisories For the AIRWOLF probe output, the system displays an aircraft that is in conflict with a precipitation hazard (as we have shown in Figure 1). Because the location of the aircraft and the precipitation hazard are known to the system, the algorithm can compute and generate an automated weather advisory. In our current advisory tool implementation, the automated weather advisories (i.e., free-text message) are displayed in a Weather Advisory View, following the en route automation modernization (ERAM) view concept (see Figure 2). Using the automated Weather Advisory View, controllers can read automated weather advisories to pilots via radio. Automated weather advisories could support the controller by (a) eliminating the need for a manual integration of traffic and weather data, (b) reducing cognitive load by eliminating the need to manually produce a weather 2015 Hogrefe Publishing