Revolutionary transformation to Next Generation Air Traffic System & impacts to Federal Aviation Administration's weather architecture

As weather information services are crucial in supporting both the safety and efficiency of the National Airspace System (NAS), the Federal Aviation Administration's (FAA) weather architecture fulfills an important role in the transition to the Next Generation Air Traffic System (NGATS). Previous reports on aviation weather services (i.e., aviation industry, FAA, et al) indicate that approximately one-fourth of all aircraft accidents and one-third of fatal accidents were weather-related. Also mentioned was the fact that weather continues to be a major factor adversely affecting NAS capacity, contributing to approximately three-fourths of system delays greater than 15 minutes. With the expectation of three times the demand on capacity in 2025, weather impact mitigation becomes increasingly crucial. To mitigate these safety and efficiency constraints, aviation weather capabilities in the NAS must undergo major changes.

The FAA determined that the primary gaps in weather information services today are in dissemination, detection and prediction. To meet the needs of NGATS requires improved dissemination to all users, new sensors and enhanced algorithms on current sensors, and continued funding of aviation weather research. The Joint Program and Development (JPDO) Office has stated that the NGATS vision can only be achieved through revolutionary system-wide transformation, with emphasis on the ability of service providers to focus on the user. The transformation of the current point-to-point communications to the NGATS net-centric weather capability ensures all users receive required weather information in real-time in a user context format. New sensors on the ground, airborne and on satellites provide significantly improved detection of hazardous weather. Continued weather research resolves forecasting deficiencies such as 8-hour convective forecasts necessary for traffic management. But what are the implications to the NAS Weather Architecture?

The FAA begins a revolutionary transformation of the NAS in all services including weather. The NAS transformation occurs in two basic steps from now and 2025. Between now and 2015, direct connections to weather sensors will be minimized (except for local display) as data and/or products are routed via a net-centric capability to end-users or to a 4-D database for later extraction. This reduction of connections to sensors, users, and processors enables real time dissemination throughout the NAS as well as cost savings. Many more aircraft have weather sensors/algorithms to provide weather information to other users directly and via the NGATS 4-D database. All observations are sent to the 4-D database, where they are integrated with weather forecasts to provide the single source of authoritative weather for any geographical location and altitude.

For the FAA, the net-centric System-Wide Information Management (SWIM) system subsumes the FAA weather communications systems functionality. These systems include the Weather Message Switching Center Replacement (WMSCR), two Weather and Radar Processor (WARP) subsystems (the FAA Bulk Weather Telecommunications Gateway and the Weather Information Network Server) and the communications portion of the Automated Weather Observing System (AWOS) Data Acquisition System (ADAS).

After 2015, the FAA weather processors, currently optimized by domain (e.g., en route and terminal), converge their functionality, which is transferred to the NGATS forecasting capability. The convergence of the weather processors, Weather and Radar Processor (WARP – en route), Integrated Terminal Weather System (ITWS) and Corridor Integrated Weather System (CIWS – traffic management) reduces duplicative functions, as well as operations and maintenance costs. The NGATS forecasting capability subsumes nearly all weather processing, both of aviation-specific algorithms (e.g., gust front, convection, turbulence, and icing), as well as weather models from the NGATS agencies. However, detection and alerts of microburst/wind shear may remain local in the near term until latency requirements can be assured and the Next Generation Weather Radar (NEXRAD) mosaic processing for display to en route controllers transfers to local processing capability.

FAA-sponsored aviation weather R&D efforts will provide improved safety with the emergence of new forecast products such as enhanced in-flight icing and turbulence gridded products, which include severity. In terms of capacity, thunderstorms contribute the most to NAS weather-related delays and aviation weather research will enable the FAA to develop thunderstorm forecasts to meet traffic management needs of current forecasts out to 8 hours. Initially, new weather R&D products will be displayed on weather processors and accessible to users. By 2015, many of these products are integrated into decision support tools of both FAA service providers and users to optimize algorithm performance for trajectory calculations, and capacity determination, etc. Subsequently, probabilistic forecasts are fully integrated into decision support tools to incorporate both the uncertainty in forecasts and traffic demand to provide traffic managers with enhanced capacity forecasts that minimize the loss of usable airspace.

The roadmap of the revolutionary changes needed to meet NGATS is still under development. The challenge for the FAA – employ sound system engineering principles on the innovative NGATS' visions to transform the NAS weather architecture to meet users' needs.