European Regional Monitoring Agency

The European agency for RVSM monitoring.

Status of EUROCONTROL Height Monitoring Units – Updated on 15/04/2024

LINZ and NATTENHEIM HMU are fully operational.

GENEVA HMU is operating with a reduced service due to technical problems.

Please do not plan any special HMU overflights in GENEVA.

The European Regional Monitoring Agency (EUR RMA) is responsible for monitoring and supporting aircraft operations in European Reduced Vertical Separation Minima (RVSM) airspace.

The individual responsibilities include:

  • Verifying operator compliance with RVSM approval requirements;
  • Monitoring aircraft height keeping performance;
  • Conducting airspace safety assessments as required by the ICAO Regional Planning Group.


The EUR RMA maintains a database of all operators and aircraft that have been issued an approval to operate with a 1,000 ft vertical separation in RVSM airspace, by one of the States accredited to it.

All civilian aircraft intending to operate in designated RVSM airspace are required to be approved by their Competent Authority.


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.

Operators can be monitored through various means and in any region.

EUROCONTROL operates 3 fixed, ground based Height Monitoring Units (HMU) to support monitoring in European airspace.

The three European Height Monitoring Systems are deployed at the following locations:

  • Geneva in Switzerland - 46°21’49”N….005°55’34”E (near GVA VOR);
  • Linz in Austria - 48°12’08”N....014°17’35”E (near LNZ VOR);
  • Nattenheim in Germany - 49°56’45”N….006°33’25”E (near the Bitburg airfield (EDRB) with coordinates N49 56,7 and E006 33,9; please note that PPR is required – See the ‘contact us’ for the telephone numbers of Maastricht and Karlsruhe UAC Supervisors who can provide more information).

The coverage of each HMU has a radius of 45 NM.

These systems are fully automatic and designed to operate 24 hours a day, 365 days of the year,  however, the operator is advised to confirm the serviceability of the HMUs before conducting a dedicated height monitoring flight. Please see the latest HMU status above.

Any aircraft transmitting an 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.

To ensure the accuracy of the result, it is necessary for the aircraft to fly straight and level for a minimum of five minutes within the coverage area defined above.

In accordance with AIP ENR 1.3-1, as published by the German Authorities, aircraft operators are required to submit a Prior Permission Required (PPR) at least three (3) hours in advance if they intend to fly an aircraft over the Nattenheim HMU specifically for RVSM monitoring purposes.

Similarly, it is advised to contact the Geneva ACC at least three (3) hours in advance if they intend to fly an aircraft over the Geneva HMU specifically for RVSM monitoring purposes.

Advance notifications will help ATC ensure the aircraft can be operated in straight and level flight in the busy and complex nature of the airspace over the HMUs and thereby contribute to an accurate height monitoring measurement.

Please use the contact telephone numbers for the Maastricht, Geneva and Nattenheim (Karlsruhe) UAC Supervisors for details of how to submit a PPR.

Providing the flight produced a successful height monitoring result, confirmation will be available, via the section below, approximately 4 weeks after the flight.

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 here, only if a valid RVSM approval is listed in the EUR RMA approvals database for the aircraft/operator.

Results for aircraft registered in States accredited to the EUR RMA will be published below.

Results for aircraft registered elsewhere will be published via the RMA for the aircrafts State of registration.

Monitoring results

In the following EUR RMA Monitoring Results page, aircraft operators can check the date of their last successful height monitoring measurement. Whilst the EUR RMA calculates the Altimetry System Error for flights conducted over the Height Monitoring Units, only the date of the last successful measurement is published. (Successful in this context refers to the fact that sufficient data regarding the flight was available to support the assessment. It does not indicate compliance with performance requirements).

The RMA Monitoring Results page can also be used by State authorities to review the RVSM approval and monitoring status of fleets of aircraft under their responsibility.

Please note that:

  • The EUR RMA does not provide height monitoring results directly to the operators.
  • The queries provide only RVSM approved aircraft, which are registered by states or operators from states accredited to the EUR RMA only.
  • The data presented includes only results from the European monitoring programme captured within the last 2 years.
EUR RMA Monitoring Results

European Regional Monitoring Agency - Monitoring results


The EASA reference document on RVSM is their Certification Specification and Acceptable Means of Compliance for CS-ACNS.

The following ICAO documents, available for purchase on the ICAO website, are pertinent to RVSM:

  • ICAO Doc 4444 - Procedures for Air Traffic Management 
  • ICAO Annex 2 - Rules of the Air
  • ICAO Annex 6 - Operation of aircraft
  • ICAO Annex 11 - Air Traffic Services
  • ICAO Doc 7030 - Regional supplementary procedures
  • ICAO Doc 9937 - Manual of Operating Procedures and Practices for Regional Monitoring Agencies
  • ICAO Doc 9574 - Manual on Implementation of 1000ft VSM between FL290 and FL410 incl.

They are available for purchase on the ICAO website.

State and military aircraft

Due to differences in technical system architecture, some military aircraft have difficulty in complying with RVSM specifications. However, within European RVSM airspace, non-RVSM approved State aircraft operating as General Air Traffic (GAT) may be provided with a minimum vertical separation of 600 m (2000f.t) instead of 300 m (1000 ft.) from all other IFR aircraft, on the condition that appropriate entries are made in fields 8, 10 and 18 of the flight plan (an M in item 8, no W in item 10 and ‘STS/NONRVSM’in item 18).

Military authorities must be aware that any deviation from the initial aircraft type certificate – through a Supplemental Type Certificate for example – will necessitate an RVSM compliance check for the new design. Some States have a regulator for military/State aircraft requiring the same compliance, training, maintenance, approval oversight as its civilian counterpart.

State aircraft with RVSM approval, and with a W recorded in item 10 of the flight plan, can operate in designated RVSM airspace with 1000 ft. separation from other IFR aircraft. To help ensure the safe and efficient operations of State and military aircraft in an RVSM environment, guidance can be provided to military users, which takes into account the specific nature of their needs.

For further information on the operation of State aircraft in designated RVSM airspace, please consult our Guidelines for the Certification and Operation of State Aircraft.