You are here: Home Past Seminars 7th Seminar - Barcelona, Spain - July 2007 Papers Macroscopic Workload Model for Estimating En ...
Document Actions

Paper 37 -- Macroscopic Workload Model for Estimating En Route Sector Capacity

The capacity of an en route sector is limited by controller workload rather than aircraft separation standards. Estimates of sector capacity are important because they provide the basis for traffic flow management alert thresholds. The results of this paper indicate that there are sometimes large errors in operational capacity estimates, particularly for small sectors. The paper presents a simple workload model that allows one to estimate sector capacity based on traffic flow characteristics and sector geometry. Its analytical nature has allowed us to fit its predictions to peak observed clear-weather traffic counts for hundreds of US en route sectors. Although lack of traffic demand causes most sectors to peak below the modeled design capacity, the “frontier” trend for the maximum count is consistent with the model predictions. The model predicts an approximate square-root relationship between sector capacity and sector volume. This non-linear relationship also appears in the observed traffic counts and helps quantify some common air traffic management observations. Because capacity grows more slowly than sector volume, small sectors can handle higher traffic density than large sectors. (In fact, today’s principal means of accommodating density growth is to reduce sector size.) However, because workload limitations demand that all sectors have comparable controller teams when operating at capacity, smaller sectors, which are limited to smaller absolute aircraft counts, experience lower ATM productivity (aircraft/controller). The model separately quantifies conflict workload and coordination workload and shows that, at capacity, conflict workload dominates. One unexpected finding is that conflict workload is even more dominant in smaller sectors because it increases as the square of traffic density. The model’s ability to identify dominant workload factors may help define the effectiveness of alternative proposals for future ATM task automation. Its ability to relate capacity to traffic flow and sector geometry may be useful in tactical re-routing when storms or other disturbances alter sector airspace volumes.
Theme: Network and Traffic Flow Optimisation
Keywords: ATM Modeling, Air Traffic Flow Management, Air traffic control complexity, Airspace Sectorization, Airspace design, Airspace Structure, Benefits Estimation, Capacity estimation, Complexity, Control Workload, Controller Workload, Dynamic Density, Monitor alert parameter, Sector Capacity, Workload, Workload evaluation
Posted by: Jerry Welch
Note: Unset Received On Jan 24, 2007

| Site Map | Accessibility | Contact |

Hosted and maintained by EUROCONTROL