Quantifying Convective Delay Reduction Benefits for Weather / Atm Systems

This paper investigates methods for quantifying convective weather delay reduction benefits for weather/ATM systems and recommends approaches for future assessments. This topic is particularly important at this time because: 1. Convective weather delays continue to be a dominant factor in the overall National Airspace System (NAS) delays, and 2. Benefits quantification and NAS performance assessment have become very important in an era of significant government and airline budget constraints for civil aviation investments. Quantifying convective weather delay benefits for ATM systems has proven to be quite difficult since the delays arise from complicated, highly variable, poorly understood interactions between convective weather and a very complex aviation system. In this paper, we consider key aspects of convective weather disruptions of the aviation system, how the weather severity can be characterized, and discuss practical experience with benefits quantification by a variety of approaches. The paper concludes with recommendations for a methodology to be used in future convective weather delay reduction quantification studies. *This work was sponsored by the Federal Aviation Administration under Air Force Contract F19628-00-C0002. Opinions, interpretations, conclusions, and recommendations are those of the authors and are not necessarily endorsed by the United States Government. Introduction The main contribution of this paper is to discuss how convective delay benefits can be estimated for various ATM systems. This topic is very important given the significant growth in convective season delays in 2004 (figure 1). Strengths and weaknesses of user interviews/modeling and comparisons of measured delays for benefits assessment are discussed based on actual usage for a variety of systems and, user locations. Figure 1. U.S. OPSNET delays by month. Note the dramatic increase in delays in the summer months characterized by convective weather. The delays for much of the summer of 2004 exceeded the delays for any of the seven previous years. Many different ATM systems can contribute to reducing convective weather delays. Contemporary convective weather information systems (e.g., CCFP, ITWS, CIWS, WARP) provide (to varying degrees) information on the weather impacts. Traffic flow management and automation tools assist in developing and executing the convective weather mitigation plans. These include ETMS (CRCT,