Reliability is an important element of maintenance support which usually forms a required part of any maintenance organization approval. It is defined as the probability that a component or a system will perform its intended function adequately for a specified period of time, or will operate in a defined environment without failure.
Data on the time in service of removed aircraft components is collected and shared with the Original Equipment Manufacturer (OEM). Both are expected to carry out analysis of this data to provide awareness of issues relating to component life of inspection which might provide evidence of a case for change, whether within a particular maintenance organisation, across all the affected maintenance organizations or in Original Equipment Manufacturer (OEM) input. Mean Time Between Failure (MTBF) is an important benchmark in reliability and is slightly less than the duration which might be expected as ‘wear-out’ or ‘design life’ is approached because of the occurrence of ‘infant mortality’ in the period immediately following component installation - the so-called Bathtub Curve.