Available Operational Time Window: A Method for Evaluating and Monitoring Airline Procedures

Time is a widely accepted means for evaluation of procedures used in the management and control of complex, dynamic systems, such as airliners. Time provides a common unit of measurement of operator performance in the context of the task in both naturalistic and experimental conditions. Time is also correlated with errors, operational efficiency, and task loading. Analytical and simulation methods used for the design and evaluation of procedures require information on the allowable operational time window (AOTW). For complex, dynamic systems, such as airliners, the AOTW exhibits a high degree of variance. The statistical properties of the AOTW have not been readily available to designers. The recent availability of flight data monitoring/flight operations quality assurance, typically used for aircraft performance and maintenance purposes, provides the means to characterize the statistical properties of the AOTW. This paper describes an analytical method to characterize the statistical properties of the AOTW (e.g., 5th percentile) for use in the design and evaluation of procedures. The method is demonstrated in a case study of an airline takeoff procedure.