Abstract:

Cabin air environment of civil aircraft contains large numbers of parameters that are coupled with each other. It is a kind of environment that humans directly contact and sense， affecting human comfort and health. The comprehensive evaluation of air environment aims to clarify the key factors affecting human senses， compare the advantages and disadvantages among different design schemes， and provide guidance for system design optimization. Among various comprehensive evaluation methods， weight coefficient， which directly affects the results of comprehensive evaluation， is the most critical but difficult index to define. Weight analysis methods can be generally divided into subjective methods and objective methods， and their calculation principles are multifarious. Existing studies generally select only one method to determine weight， but it is impossible to judge whether the selected method is suitable for the comprehensive evaluation in their field， so it is difficult to tell the reference value of these weight results. Starting from the cabin air environment parameters series， two subjective methods and two objective methods which are commonly used， are selected to analyze weight， and results comparison are completed based on the same surveyed flight data.Results show that subjective methods and objective methods of determining weight have different meanings： subjective methods reflect the level of people’s attention on different parameters， while objective methods reflect the difference level in cabin air control of different aircraft types. It is suggested to use both two methods to get a more all-sided evaluation conclusion. In addition， all aircraft types have relatively consistent level of cabin air control， but temperature， pressure and humidity are still the parameters that people pay more attention to， so the technical innovation of relevant systems should be attached importance to.

Key words: civil aircraft, air environment, comprehensive evaluation, weight coefficient, subjective methods of determining weight, objective methods of determining weight