Difference between CAMO and CAO

As soon as an aircraft enters operational service after manufacture, it must be ensured that it is permanently in airworthy condition during the period of service.

Many components of an aircraft have a limited useful life, requiring periodic replacement or maintenance. Typical parameters that influence the operational capability of aircraft and components are the time since commissioning, the flight hours, the number of takeoffs and landings, the area of operation and the purpose of use. Back in the early days of aviation, aircraft maintenance activities were carried out on the basis of experience gained by the engineers, often regardless of these parameters.

Part-CAMO and Part-CAO as legal basis

Nowadays, the maintenance of aircraft is strictly carried out according to legal requirements and is planned and determined by an organisation authorised by aviation authorities. The European Union Aviation Safety Agency has issued regulations that govern the manufacture, maintenance and operation of aircraft under its responsibility in a harmonised and safe manner.

In common parlance, both CAO- and CAMO-approved organisations are oftentimes referred to collectively

as "CAMO" and are not further classified. This is probably because both organizations have management privileges but with a different scope of aircraft. However, a closer look reveals that there are quite a few existing differences.

While Part CAMO sets requirements for all aircraft operators, the Combined Airworthiness Organisation (CAO) is responsible for maintenance and continuing airworthiness management of noncomplex aircraft.

According to the EASA definition, a complex aircraft has these characteristics:

An aeroplane

- with a maximum take-off mass of more than 5.700 kg, or

- with a cabin configuration for more than 19 passengers, or

- requiring at least two pilots to operate, or - equipped with one or more jet engines, or with more than one turboprop engine.

A helicopter

- with a maximum take-off mass exceeding 3.175 kg, or

- with a cabin configuration for more than 9 passengers, or

- the operation requires at least two pilots.

A tilt-rotor aircraft

EASA draws a sharp line with this definition and downgrades aircraft that do not exceed certain characteristics to non-complex aircraft. So a noncomplex aircraft is simply not a complex aircraft. But sometimes the application of this definition is not helpful at all:

although light twin-engine turboprop aircraft would meet these criteria, an exemption has been agreed at EU level for the non-commercial operation of twinengine turboprop aircraft with a maximum take-off mass of less than 5,700 kg.

Furthermore, Part-CAMO includes significantly more restrictive requirements. In contrast, the Part-CAO represents a simplification for operators, meaning that CAO-approved organizations must follow less stringent rules as the certification only applies to noncomplex, non-commercial aircraft. A switch to PartCAO may therefore be accompanied by relief.

Easements can be found on the side of the providers of airworthiness management as well. While on the one hand two separate approvals, the Part-CAMO for continuing airworthiness and additionally Part-145 for aircraft maintenance, must be obtained, for CAOapproved organizations both are combined, with only

one approval resulting at the end. There is a formal distinction between ‘continuing airworthiness’ and maintenance: Continuing airworthiness being the concept of managing the various procedures and actions required to keep an aircraft airworthy, and maintenance being the physical work performed, only responsible for carrying out the contracted work correctly.

Within Part-CAMO, a distinction must be made between line and base maintenance. Base maintenance includes activities which require the aircraft to be taken out of service for an extended period of time and special equipment only available in a hangar, whereas line maintenance activities are mostly carried out during normal turnaround periods where the aircraft is on the ground. Contrary to PartCAO, where there is only maintenance.

AAC joins the PRIMUS AERO family

Since the beginning of October, the Austrian Aircraft Corporation (AAC) has been part of the PRIMUS AERO family, meaning that PRIMUS AERO is now able to offer Line and Base Maintenance for Piston Engine Aircraft, Turbojets, and Jet Engine Aircraft at three locations in Austria. As a result of this merger, both customer bases benefit from the combined knowhow, more available resources, and generally better support.