Abstract: Aircraft height keeping performance (HKP) is one of the most important factors that affect airspace operational safety. On the basis of summarizing the definition, elements and quantification indexes of HKP, a formula to calculate the HKP in highaltitude airspace is derived. At the same time, a method to fit the height deviation sample with fixed intervals based on exponential power distribution and Gaussian-double exponential distribution is presented to capture the high-peak and fat-tail characteristic of the height deviation sample, and then the fitting goodness is analyzed accordingly by a likelihood ratio test. The highaltitude HKP of current Chinese airspace is assessed finally, and the result indicates that the HKP meets safety requirements well.

Key words: air traffic management, height keeping performance, exponential power distribution, Gaussian-double exponential distribution, likelihood ratio, testing