The Airbus fleet is ageing and all the researches in the past agree upon the fact that there is an ageing effect for commercial aircraft with respect to the amount of maintenance to be performed. This paper constructs a model to investigate the start of ageing and the steepness of the aircraft maintenance ageing curve. For both components and the airframe are the different parameters related to ageing defined. These parameters are reviewed with respect to their impact on the amount of maintenance performed over time. For scheduled maintenance this is done by a Maintenance Planning Document extraction of the additional ageing related maintenance tasks. Unscheduled maintenance is assessed by regression analysis of the Pilot Reports, Maintenance Reports and Mean Time Between Unscheduled Removals of components.