The method of achieving efficient and economical servicing with the maximum rate of utilisation of aircraft, is a problem which always confronts the aircraft operator, either a private owner flying his modest machine or a national airline with a variety of large and expensive aircraft. From the point of view of safety, their problems are the same.

Efficient servicing is closely related to safety in so far as the airworthiness aspect is concerned and, under present servicing methods, the direct cost of providing this aspect of safety may well amount to some 20 per cent, of operating costs; to this must be added the delays inseparable from major maintenance work which can reduce earning capacity as a result of the time taken to rectify defects. Invariably the cost to the private owner is higher than he had expected and, unless his aircraft is maintained by a competent servicing organisation, it can be subjected to frequent bouts of unserviceability—usually when he needs it most.