In order to ensure that the overall safety objectives for the air traffic services (ATS) system can be met, all aircraft operating in airspace where RVSM is implemented are required to hold an approval, issued by the State of the Operator or State of Registry as appropriate, indicating that they meet all the technical and operational requirements for such operations. This requirement, and the responsibility of States with regard to the issuance of these approvals, are specified in Annex 6, Part I — International Commercial

Air Transport — Aeroplanes, 7.2.3 b) and Annex 6, Part II — International General Aviation — Aeroplanes, 7.2.3 b). Doc 9574 indicates that there is a need for system performance monitoring during both implementation

Planning and the post-implementation operational use of RVSM. The principles and procedures for monitoring are described in Chapter 6 of Doc 9574. In all regions where RVSM has been implemented, Regional Monitoring Agencies (RMA) have been established, by the appropriate Planning and Implementation Regional Groups (PIRGs), to undertake these functions. The objectives of the RVSM monitoring programme include, inter alia:

a) Verification that the RVSM approval process remains effective;

b) Verification that the target level of safety will be met on implementation of

RVSM, and will continue to be met thereafter;

c) Monitoring the effectiveness of the altimetry system modifications which have

been implemented to enable aircraft to meet the required height-keeping

performance criteria; and

d) Evaluation of the stability of altimetry system error (ASE).