Pii: S0951-8320(99)00062-9

Airline maintenance operations affect the potential for flight delays and can also affect flight safety if signals of technical problems are missed or misinterpreted. In this paper, we use a probabilistic risk analysis model, represented by an influence diagram, to quantify the effect of an airline’s maintenance policy on delays, cancellations and in-flight safety. The model represents the leading edge (LE) sub-system of a commercial passenger jet and consists of three tiers: (1) a set of management decision variables (e.g. the level of qualification of maintenance personnel); (2) a ground model linking policy decisions and flight delays; and (3) an in-flight model, linking policy decisions, maintenance quality and flight safety. To illustrate this model, we use data adapted (for confidentiality reasons) from a study of an existing airline. Clearly, the LE devices of an airplane are not among the most safety-critical and the risk of an accident due to poor maintenance is extremely small, but non-zero. The same model can be used for other, more critical parts of the aircraft to support maintenance policy decisions in which the trade-off between delays and safety may be more pronounced. q 2000 Elsevier Science Ltd. All rights reserved.