Part 43 and approved maintenance organisations

Learn more about the maintenance activities an approved maintenance organisation (CAR 30 or Part 145) may perform once Part 43 is made and commences.

Who should read this

  • Registered operators
  • Approved Maintenance Organisations – CAR 30 or Part 145
  • Licensed aircraft maintenance engineers
  • Aircraft maintenance engineers
  • Aviation maintenance technicians

What maintenance can an approved maintenance organisation perform on an aircraft under Part 43?

An approved maintenance organisation (AMO) can perform all maintenance on a Part 43 aircraft, provided the maintenance is covered by the AMO's certificate/approval. To undertake the maintenance the AMO must have appropriate facilities, tooling, data and licensed personnel.

If an AMO maintains a Part 43 aircraft, will they have to hand in their current certificate?

No. However, if an AMO only wants to maintain small, normal category Part 43 aircraft, they could surrender their certificate of approval and continue providing maintenance within the scope of the certifying licensed aircraft maintenance engineers (LAME) licence.

Will AMOs need an inspection authorisation for annual inspections?

No, if the annual inspection is within the scope of their approval.

Both Part 145 AMO and CAR 30 organisations are required to have processes for appointing people who are qualified for the task to carry out or supervise inspections, hence no inspection authorisation (IA) is required.

When carrying out maintenance on a Part 43 aircraft in an AMO, will the LAME sign for and on behalf of the AMO or on their own licence?

The LAME would sign for and on behalf of the AMO, provided the AMO is authorised to carry out the maintenance.

How will an AMO authorise a LAME to carry out annual inspections?

An AMO will need to ensure the person certifying for the annual inspection, or compliance of major modifications and repairs, is competent and has adequate knowledge of the annual inspection and airworthiness review process, understands the aircraft certification basis, and has access to the aircraft's modification and repair data and AD compliance records. The level of training and knowledge should be equivalent to that required by a CASA authorised IA holder. The AMO should have procedures in their exposition, or quality manual if a CAR 30, describing how they train and authorise a person.

If a LAME who is authorised to certify for annual inspections holds a credit for completing an IA training course, that would satisfy the requirement.

Managing aircraft continuing airworthiness

Many registered operators (RO) leave their aircraft logbooks with their maintenance provider (AMO) and rely on the AMO to control the maintenance and airworthiness of their aircraft. While this arrangement is common under current 1988 legislation, the RO is still responsible for the aircraft's continuing airworthiness. Part 43 will not change the ROs airworthiness control responsibilities.

Under Part 43, the RO for a large aircraft > 5700kg, or transport category aircraft, must nominate a person who will be responsible for the continuing airworthiness of the aircraft – similar to the maintenance controller under the current 1988 legislation which means that the AMO would be communicating with that person.

Will the AMO be responsible for ensuring all inspections and maintenance are carried out?

No. The aircraft's RO will be the sole person responsible for the aircraft's continuing airworthiness. The AMO is only responsible for carrying out the inspections or maintenance the RO has requested to be undertaken.

How will the AMO know what inspections or maintenance are required?

The RO will be responsible for informing the AMO of the required inspections or maintenance. This may be done via a work order.

When carrying out an annual inspection, in addition to the actual aircraft inspection, the AMO will be required to check compliance with its type certification basis, that applicable ADs, and airworthiness limitations have been complied with and that all major modifications and repairs have been carried out in accordance with approved data.

Will the AMO be required to fix all airworthiness defects found during an inspection before releasing the aircraft to service?

No. The RO may decide to have someone else rectify any defects found during an inspection. The AMO will be required to make a record of the inspection carried out (in the aircraft logbook) including a statement that the:

  • aircraft is not approved for return to service
  • AMO has provided the RO with a signed and dated list of the defects found.

How will an AMO deal with any undocumented modifications or repairs?

If undocumented modifications or repairs are found during an inspection, the AMO may:

  • contact the RO and seek further information
  • list the modification or repair as a defect
  • if appropriate data is available, approve the modification or repair
  • if the modification or repair is a minor modification or repair, the AMO may inspect it and if satisfied the aircraft remains at least equal to its original or properly altered condition (with regard to aerodynamic function, structural strength, resistance to vibration and deterioration, and other qualities affecting airworthiness), then the AMO may approve the work.

How does an AMO release a Part 43 aircraft to service after an annual or 100-hour inspection?

The CAR 30 will issue a maintenance release (MR), or alternative if the RO is using something other than an MR, in accordance with the AMO's procedures. It is not necessary to list future scheduled maintenance; however, the organisation will need to issue a list of defects if any. These could be listed in Part 2 of the MR with a note in Part 1 that the aircraft is unairworthy until the defects are rectified as appropriate.

A Part 145 AMO would issue a certification that the inspection has been completed and that the aircraft is or is not approved for return to service.

In both cases, as well as providing the RO with a list of defects if any, the AMO must also ensure that unserviceable controls or systems are clearly placarded as unserviceable.

Note: How the RO chooses to record flight hours, cycles etc is up to the RO. They may use the MR, a tech log, record the details straight into the logbook or some other system.

What are the records that an AMO will be required to make, keep, or update?

For more information, please refer to the following information sheets:

  • Requirements for maintaining records
  • Releasing an aircraft or component to service.

Could an AMO's licensed aircraft maintenance engineer use Part 43 extended licence privileges on all aircraft maintenance?

No. The extended LAME privileges may only be exercised on Part 43 aircraft.

What documentation for a part or component will be required to fit a part to a Part 43 aircraft, including parts bought from distributers, salvaged parts or parts which have had maintenance performed on them under Pt 43?

Part 43 requires 'the use of materials of such quality that the aircraft etc. worked on will be at least equal to its original or properly altered condition'. The LAME will need to ensure any part or material meets the specifications and has the traceability that demonstrates the part or material is equivalent to that used in the manufacture of the part or material. Evidence could include a Form 1, Serviceability tag, Component history record, component logbook, etc.

Note 1: components and appliances maintained under part 43 ( an independent LAME) are not eligible for a CASA Form 1.

Note 2: A CASA Form 1 is not required for components maintained and installed outside of an AMO. If an AMO, during maintenance of a Part 43 aircraft, finds components fitted that were released to service by a LAME (no Form 1) that is not a defect.


The content provided in the information sheet is a guide only as to how the rules may work in practice once Part 43 is made and commences.

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