International Maintenance Review Board Policy Board (IMRBPB)

The International Maintenance Review Board Policy Board (IMRBPB) is a body set up by aviation regulatory authorities and agencies (also known as National Aviation Authorities – NAAs) for the continuing development of policies, procedures and guidance in the performance of Maintenance Review Board (MRB) or Maintenance Type Board (MTB) process, and in the application of the Maintenance Steering Group (MSG-3) logic as part of these MRB/MTB process. In addition to promoting harmonisation between the NAAs, the IMRBPB advocates the standardisation of MRB/MTB policy and procedures through a structured forum for discussions, leading to the development of international policy regarding MRB/MTB activities.

There are eleven member NAAs who have signed the IMRBPB Charter, representing: Australia, Brazil, Canada, China, the European Union, Hong Kong (China), Japan, Singapore, the United Arab Emirates, the United Kingdom and the U.S.A.

In addition, industry (aircraft manufacturers and operators) are represented at the Policy Board by the following bodies: Airlines for America (A4A), specifically by the Maintenance Programs Industry Group (MPIG) under the A4A's Airworthiness Committee; the Rotorcraft Maintenance Programs Industry Group (RMPIG) under the Helicopter Association International.

The MSG-3 logic process is an industry document published by Airlines for America (A4A) that is used by every major transport category aircraft manufacturer (fixed wing and rotorcraft) to develop initial scheduled maintenance tasks that become the MRB Report (MRBR) for that type. These MRBR are used by aircraft operators as the basis for their approved maintenance programmes (or schedules or requirements) to ensure the continuing airworthiness and reliability of their fleets.

The MRB/MTB processes are harmonized through the International MRB/MTB Process Standard (IMPS). The IMRBPB has issued this standard as guidance, which outlines the standardized processes and procedures to be used by NAAs in the oversight and approval of scheduled maintenance requirements by NAAs. NAAs who are members of the IMRBPB should adopt or reference IMPS as part of their regulatory framework.

The IMRBPB reviews and approves Candidate Issue Papers presented by the NAAs and A4A members that amend the MSG-3 document and the IMPS. Following approval, the Issue Paper will be incorporated into the MSG-3 or IMPS documents at next revision.

There is currently a three year revision cycle for the MSG-3 and the IMPS documents. This revision cycle is maintained in order to implement new interpretations and to ensure new and emerging technologies are captured, while not overloading the revision cycle of the NAAs’ regulatory framework or creating a burden on aircraft manufacturers.

This website is the reference point for IMRBPB related material.


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