Methodological Approach to Determination of the Trend of Changes in Aircraft Reliability Indicators of Aviation Equipment on the Example of State Aviation Helicopters

Abstract

The problem of flight tsafety , without regard to swift scientific and technical progress in industry of aviation equipment, become exceptionally sharp in our time. The statistical processing of empiric data is an actual task in monitoring of process of exploitation of propulsion MODULE of the Armed Forces of Ukraine and determination of tendencies of technical service and repair, directions of modernisation of armament and military equipment.
 The article considers the approach of the systems to the evaluation of reliability and safety of flights in relation to accomplishment of combat missions and preventionof aviation accidents. A methodological approach to the mathematical processing of statistical information for the period 2016-2019 on malfunctions was developed. The quantitative evaluation of their level is conducted on the generally accepted standardized indexes (statistical and probabilistic), specific methodology was here used.
 Index "parameter of failure flow" that characterizes the level of operating reliability and index "level of accident rate" that characterizes safety of flights were used in this methodology on ІСАО recommendation.
 Certain trends of changes of these indexes, the “upper control limit of reliability" and the considered conception of acceptable level of safety performance ( ALoSP) are expected for future periods for the different types of helicopters.
 On the base of operating data, the prognosis indexes expected, "upper control limit of reliability" on 2020 for the specific types of helicopters. As expected, according to obtained results, for all types of helicopters the mean value of this index will make not more than 4,3 failures per 100 flight hours.
 In accordance to conception of "acceptable level of "ALoSP" it is possible to distinguish three levels or "triggers" of flights safety : Acceptable level (Acceptable), special purpose level (Target), Critical level (Alert). These "triggers" are calculated taking into account the mean value of statistical sets of data about failures (for the last 3 years) and standard deviation that gives an opportunity to define the necessary additional measures of management to provide safety of flights.
 Authors came to the conclusion that conception of ALoSP is suitable for the evaluation of efficiency to provide flights safety of aviation of the Armed Forces of Ukraine with implementation of necessary adaptation to the existent terms of application of UKR aviation.