RVSM Monitoring Requirements

All operators of aircraft approved to fly with a 1,000 ft vertical separation in RVSM airspace are required to participate in the global RVSM height monitoring programme. The number of aircraft that require monitoring depends on both the size of an operator’s fleet, and the variety of aircraft types operated.

Aircraft which are constructed and maintained to the same Type Certificate, Supplementary TC, Service Bulletin or TC amendment, and which are known to exhibit similar Altimetry System Error characteristics are categorised together in what is called an RVSM Monitoring Group. Additional information and the current structure of the RVSM Monitoring Groups can be found on the Monitoring Group sub-tab below.

Operator requirements for participation in the global Height monitoring programme are defined in ICAO Annex 6. These requirements and targets are detailed in the Monitoring Targets sub-tab below.

State authorities are required to take appropriate action to ensure compliance with monitoring targets for all operators for which they have operational authority.

Monitoring targets can be satisfied in Europe, or in any other recognised RVSM height monitoring programme, or through a combination of each. For details of other height monitoring programmes please click here.

The procedure for height monitoring by one of Eurocontrol’s Height Monitoring Units is detailed within the Procedures sub-tab below.

Monitoring Groups

Aircraft height keeping performance requirements for operation in RVSM airspace are defined in specifications called RVSM Minimum Aircraft System Performance Specification (MASPS).

Aircraft which are nominally constructed to the same design and which exhibit similar Altimetry System Error characteristics are categorised together in what is called an RVSM Monitoring Group.

The EUR RMA monitors group performance to ensure compliance with the RVSM MASPS.

An aircraft which is uniquely constructed or one which is presented for airworthiness approval on an individual basis is termed a non-group aircraft. There is no generic RVSM MASPS compliance package which may be applicable to other airframes. These aircraft are only evaluated on an individual basis and so it is mandatory for every non-group aircraft to participate in the RVSM height monitoring programme.

The EUR RMA maintains, in cooperation with all the other RMAs, a table, which defines the RVSM Monitoring Groups from the best information available. Unfortunately there is no centralised system for tracking individual STCs or Service Bulletins or comparing relative performance, to determine which require the creation of new RVSM Monitoring Groups. The current table of civilian RVSM Monitoring Groups can be found here. The EUR RMA welcomes any information which may assist in identifying changes which may be required to either modify an existing group or define a new one.

Monitoring Requirements

The EUR RMA conducts extensive evaluations of aircraft height keeping performance. Any aircraft which is non-compliant with height keeping performance requirements or which exhibits excessive aberrant behaviour is reported to the operator, State approval issuing authority and EASA for further investigation.

The EUR RMA maintains a definitive list of aircraft types and variants which have similar height keeping performance characteristics. The EUR RMA then conducts group height keeping performance assessments to identify common or generic issues. Combining aircraft together in common groups reduces the overall number of aircraft that need to be monitored to satisfy safety targets by applying statistical models to large data samples.

The EUR RMA monitors operator fleets for compliance with regional and global height monitoring targets, providing results to State approval authorities. The EUR RMA receives height monitoring data from other RVSM regions which can be used to support performance evaluations and determine compliance with monitoring targets.

Download the RVSM monitoring requirements (pdf).

Monitoring Targets

All operators of aircraft approved to fly with a 1,000 ft vertical separation in RVSM airspace are required to participate in the global RVSM height monitoring programme. The number of aircraft that require monitoring depends on both the size of an operator’s fleet, and the variety of aircraft types operated.

If an operator has aircraft from only one RVSM Monitoring Group then it is necessary to have a minimum of 2 airframes height monitored every 2 years or 1,000 total flying hours whichever is the greater. If only 1 airframe is operated then that airframe must be monitored during the same time interval. The same requirement exists for aircraft in each Monitoring Group. If you operate 3 aircraft within one RVSM Monitoring Group and another 2 aircraft from a separate group you cannot satisfy the requirement by height monitoring all 3 aircraft of the first type and only 1 of the other. The requirement is applicable for each aircraft type operated and not as a proportion of the total company fleet.

For certain aircraft types, including most new designs, the RMA recommends that operators should achieve a 60% monitoring target. This is to ensure sufficient data is obtained to verify long term performance and Altimetry System Error stability. If you are required to meet this higher monitoring target you will be informed by your State Approval Authority.

The RMA has no means to measure the amount of flight hours achieved by individual airframes and therefore only measures compliance with the 2 year time limit.

If an operator is unlikely to achieve the target of 1,000 flight hours for any one aircraft type operated within the 2 year period the matter should be discussed with their State Approval Authority as, in such circumstances, additional time may be allotted.

Monitoring targets can be satisfied in Europe, or in any other recognised RVSM height monitoring programme, or through a combination of each. .

If you have any queries regarding monitoring targets please contact the airworthiness authority responsible for issuing your RVSM approvals or the EUR RMA.

EUR HMU Monitoring Procedures

EUROCONTROL operates 3 fixed, ground based Height Monitoring Units (HMU). Their locations and operational coverage area can be found here. These systems are fully automatic and operate 24 hours a day, 365 days of the year.

Any aircraft transmitting a Mode A code, or ICAO 24-bit aircraft identifier, flying between FL 290 and FL 410 within the operational coverage area of the HMUs will be detected by the HMU systems.

The majority of monitoring results are for aircraft which are operating normal schedules which take them within the coverage of an HMU. However, some operators make specific over fights to obtain a height monitoring result for compliance with global RVSM height monitoring requirements, or for confirmation of the resolution of a reported technical problem or to satisfy airworthiness authorities.

In order to be able to conduct a successful measurement it is necessary that the HMU receives a minimum number of high quality replies within the coverage area. To ensure the accuracy of the result it is also necessary for the aircraft to fly straight and level for a minimum of five minutes. Any significant change of direction or altitude will terminate the tracking function within the HMU and may result in an unsuccessful monitoring result.

There is no requirement for operators to notify the RMA in advance of the intention to over fly an HMU for a height monitoring result; however it is advised that operators check the status message on the homepage of this website to confirm that there are no scheduled maintenance plans or long term outages. There is no requirement to submit a height monitoring request form as they are no longer used.

The Height Monitoring Units are not operational ATC systems. Furthermore their status is not monitored overnight, over weekends or during EUROCONTROL holidays. EUROCONTROL cannot accept any liability in the event of a system failure which results in an unsuccessful monitoring flight. Operators can telephone the RMA during normal working hours to check the latest status of the HMU systems by calling +32 27 29 32 31 or +32 27 29 34 54. Normal working hours are Monday to Friday 08:30 to 16:30 excluding public holidays.

Providing your flight produced a successful height monitoring result, confirmation will be available approximately 2 weeks after the flight. A monitoring result is matched to an aircraft by correlating the identifier extracted from the monitoring result with that listed in the RVSM Approvals database. If your aircraft is transmitting a different ICAO 24 bit aircraft address from that which is listed in the RVSM Approvals Record then the monitoring results will not be correlated to your aircraft.

For operators registered or approved within the EUR RVSM region or States accredited to the North Atlantic RVSM region Central Monitoring Agency, a confirmation will be posted on this page. (A result will only be posted providing a valid RVSM approval is listed in the EUR RMA approvals database for the aircraft/operator). For operators registered or approved in other RVSM regions, the confirmation will be sent to the RMA with oversight responsibility for that region of origin.

Dedicated monitoring

Operators who are RVSM approved and wish to conduct a specific flight dedicated to height monitoring should confirm the serviceability of the planned HMU on the day of the flight. A normal flight plan must be filed with the usual flight planning authorities. (The flight plan is an operator responsibility and is outside the scope of the RMA).

Approved aircraft regularly flying within the coverage of HMUs are expected to automatically fulfil monitoring requirements during normal day-to-day operations.

For a successful HMU measurement it is necessary for the aircraft to fly straight and level for a minimum of 5 minutes, between FL290 and FL410 (inclusive) and within the coverage of the HMU.

European Regional Monitoring Agency

Contact us to report technical, compliance and operational issues, for actions on RVSM height monitoring or feedback from Monday to Friday (08:30 to 16:30) excluding public holidays.

EUROCONTROL is not liability in the event of a system failure and unsuccessful monitoring flight.

Phone: 
+32 27 29 32 31
+32 27 29 34 54
Fax: 
+32 27 29 51 85