Aircraft Should Not Be Fair Weather Friends - Impact of Winds Aloft on Aircraft Operating Economics

摘要

Aircraft operators and aircraft designers make heavy use of the "deviation method" to account for geographical, weather and temperature differences in atmospheric conditions encountered by aircraft. Standard procedures to estimate en-route aircraft performance rely upon the "standard atmosphere" where real-world conditions are expressed as deviations from this standard. Operators often dispatch based on surface wind and temperature devations at origin and destination airfields and then account for an "average" wind aloft through the concept of an equivalent still air distance. This paper addresses these simplifications with a lateral and vertical weather model incorporated into a point-mass mission simulation that uses real-world atmospheric conditions. We can now determine the effect of changing atmospheric conditions on en-route performance and economy. The custom toolset was used in combination with a series of trades over a range of five days and a representation of each season to show the variation that occurs on a single route over the course of daily and seasonal periods.