2.2.1. Reliability

Despite the technological advancements over time, the demand for highly reliable and performing systems has increased due to the complexity of modern systems [18,19]. Reliability of a component/system plays a key role during the MMEL development process as it helps to analyse and predict possible failure causes through the application of engineering knowledge [19]. Reliability plays a role in both MMEL and MEL. Reliability analysis is performed during the MMEL development and justification by using the tools and techniques mentioned in Section 2.1 above, and su fficient reliability must also be ensured for MEL items during operations.

According to Airbus [3], the MMEL contributes to the operational reliability of airline operators as it optimises dispatch reliability by reducing aircraft downtime. To maintain a MEL item's reliability, servicing/scheduled maintenance is required [20], and MEL items must be inspected at predetermined time intervals prescribed by the manufacturer or regulator.
