Aerocom System

Magazine Articles

VOLARE: Let me manage your aircraft - February 1990

At the end of the 80's a series of aeronautical accidents generated the idea that they were caused by poor aircraft maintenance. Enquiries and inspections conducted by the Air Registries fortunately dispelled these doubts by confirming that the chances that maintenance activities were being carried out by incompetent personnel were highly unlikely. It must be added that for some years information technology has given a notable contribution to air maintenance, especially in relation to the difficulties encountered in the management aspects, due to the fact that in civil aviation it has exclusively a preventive function.

Every component of an aircraft is liable to fail and its failure is not only meant as its breakdown but also as a series of consequential events. A serious breakdown, for example, can be caused by the poor state of a gasket, that costs just a few dollars, which can cause a fuel leak. A large number of breakdowns can be caused by outside agents, like the not infrequent case of birds entering the radiator air intakes.

Very few things on board an aircraft are unnecessary to the point of being able to break down without compromising flight security. It is necessary then to prevent all the possible failures at any cost. In the first place it is necessary then to determine the MTBF (Mean Time Between Failures). Then the calculations of the intervals between inspections, servicing and replacements must be carried out and finally, the preventive maintenance support at each interval so determined. This philosophy has necessarily given rise to economically onerous procedures. Also, if an aircraft is always carefully managed by the user and immediately has all the inspections, without which some problems would never be revealed at the established interval, it must be subject to a general revision which can also cost thousands of dollars. The increased costs also relate to the fact that on board an aircraft there are very many components subject to preventive maintenance regulations, each of which has its own inspection interval. Also maintenance support needs to be carried out dependently from others and to the various components to be inspected, replaced, and serviced must be added the inspections to the structures and to the systems, the lubricating support and the airworthiness certificates.

For an aircraft that can be said to be "simple" in its structure, the expiries to be kept under control are, on average, a hundred and the intervals go from 25 flight hours to 10 years. In an airplane the components with a definite life limit are 60 or 70 (and become 100-150 in helicopters). To these you must add a dozen of airworthiness certificates and a couple of technical reports for the airframe and the engines. And in the case in which a single preventive maintenance record is not carried out within pre-arranged limits, the aircraft loses administrative airworthiness, as the certificate expires. Today also for the minor civil aviation operators the management of maintenance expires.

Today also for the minor civil aviation operators the management of the maintenance expiries can be an organizational and bureaucratic burden . However, the use of information technology has contributed to make this burden less serious, above all thanks to the services offered by specialist companies by being able to process the data relative to each aircraft and transfer it in real time to the operator's responsible technicians who can inspect the state of the aircraft's maintenance. The services are managed from the bases built for the users of their own models (as Cessna do with the Cescom system) or from independent companies who have created the Camp/Scamp, CALM and Aerocom SMC systems for the other types of aircraft.

All the systems are based on the reciprocal transfer of the information. This exchange generally takes place between manager and operator, establishing a close relationship, so that often the manager, who knows every piece of every machine, becomes a precious advisor. Each system offers unique features. Camp offers the technical description of the procedures needed to carry out the maintenance supports., Cescom presents a complete analysis of the expiries and the MTBF for each component installed on the aircraft of the Citation range, Aerocom SMC (the only Italian system) also supplies the non programmed maintenance history and the graphic diagram of the remaining life of all the components. Camp provides the possibility of direct connections between computers via a modem. CALM and Aerocom SMC supply a special software for the management of the expiries directly by the offices of the operation.

The services generally are supplied on the basis of an annual subscription for which the cost is amply compensated by the high quality of the management that protects the operator from the risk of a grounded machine.