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Important Things To Remember About RVSM And ADS-B Out

September 2022


How your aircraft is operated determines the specific RVSM approval requirements.

Section 3 Of Title 14 CFR Part 91, Appendix G

Section 3 refers to operators who conduct flights in RVSM (Reduced Vertical Separation Minimum) airspace where authority is issued in Operations Specifications, Management Specification, or a Letter of Authorization.

Aircraft operators conducting RVSM operations under this section must meet the RVSM Minimum Monitoring Requirements and have their aircraft monitored every two years or within 1,000 flight hours of the last satisfactory height-monitoring date on record.

Section 3 operators equipped with ADS-B out under this section, do not need to fly over an AGHME (Aircraft Geometric Height Measurement Element) station for RVSM height monitoring.

If necessary, please note there are only two AGHME (Ground Stations) available in North America: Atlantic City, New Jersey in the United States and Ottawa, Ontario in Canada.

Section 9 Of Title 14 CFR Part 91, Appendix G

Operators and pilots conducting RVSM operations under Section 9, must ensure their aircraft meet the RVSM altitude-keeping performance monitoring requirements as described in Chapter 4, paragraph 4.3 of FAA Advisory Circular 91-85B.

Under these provisions, aircraft with qualified (meets the performance standards in Title 14 CFR Part 91.227) ADS-B out systems will be monitored during normal operations whenever operating at RVSM altitudes where sufficient ADS-B data is available to the FAA to determine RVSM performance. The FAA only performs height monitoring through ADS-B on Mondays.

Fleet Operators

All aircraft in the same fleet must have been monitored within the previous 24 months and found to be in compliance with the performance requirement specified in Section 9(b) of Title 14 CFR Part 91 appendix G, which states the altimetry system error of the aircraft does not exceed 200 feet when operating in RVSM airspace.

As a fleet operator, if your aircraft are equipped the same or, basically the same, you may only need to have the monitoring completed on a portion of the fleet to have all the aircraft considered compliant.  Refer to CFR 91, Appendix G.


ADS-B-equipped aircraft must still meet the RVSM performance standards to operate in RVSM airspace. ADS-B in does not guarantee the required vertical separation from other aircraft.

If you intend to fly in international RVSM airspace where the state of authority requires specific operational authority, you must have specific authorization by Operation Specification, Management Specification, or Letter of Authorization.

GMU Height Monitoring

Duncan Aviation offers RVSM monitoring through GMU (GPS Monitoring Unit) monitoring.

For more information about RVSM or to schedule a GMU flight with a qualified Duncan Aviation technician, contact Randy Dill, RTS Inspector, at +1 402.475.2611, ext. 1449, or via email at Randy.Dill@DuncanAviation.com.