Abstract:
The air transport markets affected by global economic climate and regional demand
characteristics are evolving fairly dynamically. To cope with the evolving demand and
to penetrate desired market segments, operators' usage of aircraft has been getting
more and more dynamic with increased deviation from the originally designed mission
objectives.
The objective of this research is to investigate the effects of in-service rrusslon
variation on aircraft structural performance so as to provide airlines with a more
realistic approach toward better fleet management.
During the research, the scenarios and phenomena causing fleet in-service mission
variations were investigated. A survey on the utilisation of world-wide aircraft fleets
was conducted and presented. The in-service missions of aircraft fleets were found to
vary significantly in terms of mission profile. Furthermore, the utilisation patterns of
individual aircraft in the same fleet of a major airline are also being thoroughly
analysed. Tremendous variations of mission mixes are found among individual
aircraft.
In order to analyse the effects of the in-service mission variation, methodologies and
models based on fatigue test results have been developed by the author. Actual
service data are being input for the effect analysis. It is found that the mission
variation has a considerable engineering influence on the aircraft's structural
performance either in terms of mission airworthiness or fatigue life span.
Finally, a conceptual model, the 'Integrated Airline Fleet Management Model'
(IAFM), has been developed as a blueprint for practical application. By implementing
the IAFM, airline will be able to obtain a realistic picture of the health of its aircraft.
With a more reliable basis for maintenance planning, improved inspection accuracy,
reduced maintenance cost and better structural airworthiness can be achieved.
