Before detailing the job role of the category C licensed engineer, it is worth clarifying the major differences in the roles performed by line maintenance certifying staff and base maintenance certifying staff. In the case of the former, the inspections, rectifications and other associated maintenance activities take place on the aircraft, on the "live side" of an airfield. Thus the depth of maintenance performed by "line maintenance personnel" is restricted to that accomplishable with the limited tools, equipment and test apparatus available on site. It will include "first-line diagnostic maintenance", as required.

Base maintenance, as its name implies, takes place at a designated base away from the live aircraft movement areas. The nature of the work undertaken on base maintenance sites will be more in-depth than that usually associated with line maintenance and may include: in-depth strip-down and inspection, the embodiment of complex modifications, major rectification activities, off-aircraft component overhaul and repairs. These activities, by necessitiy, require the aircraft to be on the ground for longer periods of time and will require the maintenance technicians to be conversant with a variety of specialist inspection techniques, appropriate to the aircraft structure, system or components being worked on.

 

The category C certifier acts primarily in a maintenance management role, controlling the progress of base maintenance inspections and overhauls. While the actual work detailed for the inspection is carried out by category B technicians and to a limited extent, category A base maintenance mechanics, in accordance with the written procedures and work sheets. These individual activities are directly supervised by category B maintenance certifying technicians, who are responsible for ensuring the adequacy of the work being carried out and the issuing of the appropriate certifications for the individual activities.

The category C certifier will upon completion of all base maintenance activities sign-off the aircraft as servicable and fit for flight. This is done using a special form known as a certificate of release to service (CRS). Thus the category C certifying engineer has a very responsible job, which requires a sound all-round knowledge of aircraft and their associated systems and major components.

'Aircraft Engineering Principles' by Lloyd Dingle and Mike Tooley, Elsevier Ltd., ISBN 978-0-7506-5015-1

1) Summarize the job roles of category A Mechanic, category B Technician and category C Engineer.

2) Where can you train for category C Engineer?

3) Why is the adoption of aircraft maintenance safety culture a vital part of the education for all individuals wishing to practice as aircraft maintenance engineers?