The Federal Aviation Administration (FAA) distributes extensive amounts of data to its systems throughout the National Airspace System (NAS). The largest component of these data is weather related and the largest weather related component is gridded weather forecast data, which is generated by the National Weather Service (NWS) National Centers for Environmental Prediction (NCEP). The FAA requires data from three of NCEP’s gridded weather forecast models: Rapid Update Cycle (RUC), Eta, and Aviation (AVN). Of these models, RUC is the one most frequently required by FAA systems and, of the weather parameters forecasted by RUC, winds aloft is the one most often requested. Traditionally, the FAA’s requirement for RUC has been resolution based (i.e., ‘best available’), the impact of which has been to significantly increase the amount of these data over time. This has led to exponential growth in the cost of FAA telecommunications, delay in delivery of these data to FAA users, and increase in user storage and processing requirements. However, higher RUC output resolution does not necessarily equate to higher forecast accuracy, which would be a more effective basis for setting FAA requirements.
In an effort to control FAA telecommunication costs, MITRE’s Center for Advanced Aviation System Development (CAASD) conducted a study to determine how winds aloft forecast accuracy was impacted by reducing RUC output resolution. CAASD found that RUC II output resolution could be reduced by approximately 50% in all four forecast dimensions without degrading winds aloft forecast accuracy. This finding has encouraged NCEP to examine other RUC weather forecast parameters (e.g., temperature, relative humidity, vertical velocity) to determine whether CAASD’s finding may extend beyond winds aloft. NCEP’s goal is to possibly create two RUC II output resolutions: a high resolution for those weather parameters whose accuracy is positively impacted by finer resolution and a lower resolution for winds aloft and possibly several other yet to be determined parameters, whose accuracy is not degraded by coarser resolution. In this way, telecommunication, storage, and processing costs for both the FAA and NWS may be significantly reduced without impacting the quality of RUC forecasted weather information.
The 8th Conference on Aviation, Range, and Aerospace Meteorology