Maybe I could expand on the situation where one person appears to be responsible for the maintenance of a fleet of aircraft from experience with another company (not Virgin Blue)
The situation where all line and heavy maintenance is contracted out is a very common situation in small and medium-sized airlines.
The maintenance organisation is responsible for all maintenance, the airworthiness of the aircraft, implementation all ADs and SBs and maintaining the aircraft to an approved maintenance schedule, as approved by the CASA.
So it is the maintenance organisation, with a large staff of trained engineers and technicians that is the responsibility of the maintenance organisation, and not the airline, in this case, Virgin Blue. So it isn't that one man is responsible for the entire maintenance operation of the airline - far from it, the airline does not have a maintenance operation it is contracted out.
His role is a Liason Engineer
, to ensure that maintenance is conducted to Virgin Blue company standards and deal with any issues that need to be resolved between the maintenance organisation and the airline - he will probably also be responsible for placing contracts for the outsourcing of various engineering roles. As his job title would suggest - he is the link between the airline and the maintenance organisation.
The costs of having your own in-house engineering department are high for a small airline due to the specialist skills and equipment needed so it makes sense to outsource. As an airline grows, it becomes more and more cost effective to bring more engineering functions in-house.
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Photo © Dave Faulkner
Hope this makes some sense to everyone else reading it!