Reduced Vertical Separation Minimum (RVSM)

RVSM airspace was designed to allow 1,000 ft vertical separation between aircraft operating at flight levels (FL) at or above FL 290. At 0901 universal coordinated time (UTC) on January 20, 2005, the FAA implemented RVSM between FL 290−410 (inclusive) in the following airspace: the airspace of the lower 48 states of the United States, Alaska, Atlantic, and Gulf of Mexico High Offshore Airspace, and the San Juan flight information region (FIR). On the same time and date, RVSM was also introduced into the adjoining airspace of Canada and Mexico to provide a seamless environment for aircraft traversing those borders. In addition, RVSM was implemented on the same date in the Caribbean and South American regions.

Source: AC 91-85B, ¶B.2.1

Operations within airspace designated as Reduced Vertical Separation Minimum airspace.

(a) Except as provided in paragraph (b) of this section, no person may operate a civil aircraft in airspace designated as Reduced Vertical Separation Minimum (RVSM) airspace unless:

(1) The operator and the operator's aircraft comply with the minimum standards of appendix G of this part; and

(2) The operator is authorized by the Administrator or the country of registry to conduct such operations.

(b) The Administrator may authorize a deviation from the requirements of this section.

Source: 14 CFR 91, §91.180

Before entering RVSM airspace, the pilot should review the status of equipment required. The following equipment should be operating normally:

1) two altitude measurement systems, as defined by the RVSM MASPS;

2) automatic altitude-keeping device(s);

Note.—Redundancy requirements for altitude-keeping devices should be established by regional agreement after an evaluation of such criteria as mean time between failures, length of flight segments and availability of direct pilot-controller communications and radar surveillance.

3) at least one altitude-reporting transponder (if required for operation in that specific RVSM airspace) capable of being switched to operate from either of the two altimetry systems required by the RVSM MASPS; and

4) one altitude-alerting device;

Should any of this equipment fail prior to the aircraft entering RVSM airspace, the pilot should request a new clearance so as to avoid flight in this airspace.

Source: ICAO Doc 9574, ¶5.1.1.(g)

Implementation of RVSM is dependent on the establishment of an aircraft approval confirmation process, which is intended to exclude unqualified aircraft and operators from operating in RVSM airspace unless the appropriate separation is applied. The process may have regional variations, but the primary responsibility for confirmation of the approval status of an aircraft/operator must rest with the State of the Operator/State of Registry. The confirmation process will be facilitated by the following measures:

1. maintaining a comprehensive record of all approvals granted for operations in RVSM airspace;
2. providing the approvals records in 4.3.3 a) to the regional monitoring agency (RMA) for inclusion in its regional RVSM-approvals database; and
3. including a check of the approval status of aircraft/operators in the schedule of routine in-flight inspections.

Source: ICAO Doc 9574, ¶4.3.3

2.2 Aircraft Eligibility. An aircraft is an “RVSM-Compliant Aircraft” when:

1. The aircraft design ensures the aircraft will meet RVSM performance requirements; and

2. The aircraft has been properly maintained on an ongoing basis to conduct such operations.

2.2.1 Aircraft may be produced RVSM-compliant or brought into compliance through the application of appropriate Service Bulletins (SB), Service Letters (SL), Engineering Change Orders (EO), or Supplemental Type Certificates (STC). For airworthiness guidance, see Appendix A, RVSM Airworthiness Certification.

2.2.2 To determine eligibility for RVSM operations, the limitations section of the Airplane Flight Manual (AFM) or AFM Supplement (AFMS) should indicate the aircraft has been determined to be capable of meeting the RVSM performance requirements of 14 CFR part 91 appendix G.

Note: For operators and pilots authorized under part 91 appendix G, section 9, the aircraft may have qualified as Group or Non-Group aircraft described in Appendix A.

Source: AC 91-85B, Ch. 2

(a) Except as specified in Section 9 of this appendix, an operator may be authorized to conduct RVSM operations if the Administrator finds that its aircraft comply with this section.

(b) The applicant for authorization shall submit the appropriate data package for aircraft approval. The package must consist of at least the following:

(1) An identification of the RVSM aircraft group or the nongroup aircraft;

(2) A definition of the RVSM flight envelopes applicable to the subject aircraft;

(3) Documentation that establishes compliance with the applicable RVSM aircraft requirements of this section; and

(4) The conformity tests used to ensure that aircraft approved with the data package meet the RVSM aircraft requirements.

(c) Altitude-keeping equipment: All aircraft. To approve an aircraft group or a nongroup aircraft, the Administrator must find that the aircraft meets the following requirements:

(1) The aircraft must be equipped with two operational independent altitude measurement systems.

(2) The aircraft must be equipped with at least one automatic altitude control system that controls the aircraft altitude—

(i) Within a tolerance band of ±65 feet about an acquired altitude when the aircraft is operated in straight and level flight under nonturbulent, nongust conditions; or

(ii) Within a tolerance band of ±130 feet under nonturbulent, nongust conditions for aircraft for which application for type certification occurred on or before April 9, 1997 that are equipped with an automatic altitude control system with flight management/performance system inputs.

(3) The aircraft must be equipped with an altitude alert system that signals an alert when the altitude displayed to the flight crew deviates from the selected altitude by more than:

(i) ±300 feet for aircraft for which application for type certification was made on or before April 9, 1997; or

(ii) ±200 feet for aircraft for which application for type certification is made after April 9, 1997.

(d) Altimetry system error containment: Group aircraft for which application for type certification was made on or before April 9, 1997. To approve group aircraft for which application for type certification was made on or before April 9, 1997, the Administrator must find that the altimetry system error (ASE) is contained as follows:

(1) At the point in the basic RVSM flight envelope where mean ASE reaches its largest absolute value, the absolute value may not exceed 80 feet.

(2) At the point in the basic RVSM flight envelope where mean ASE plus three standard deviations reaches its largest absolute value, the absolute value may not exceed 200 feet.

(3) At the point in the full RVSM flight envelope where mean ASE reaches its largest absolute value, the absolute value may not exceed 120 feet.

(4) At the point in the full RVSM flight envelope where mean ASE plus three standard deviations reaches its largest absolute value, the absolute value may not exceed 245 feet.

(5) Necessary operating restrictions. If the applicant demonstrates that its aircraft otherwise comply with the ASE containment requirements, the Administrator may establish an operating restriction on that applicant's aircraft to restrict the aircraft from operating in areas of the basic RVSM flight envelope where the absolute value of mean ASE exceeds 80 feet, and/or the absolute value of mean ASE plus three standard deviations exceeds 200 feet; or from operating in areas of the full RVSM flight envelope where the absolute value of the mean ASE exceeds 120 feet and/or the absolute value of the mean ASE plus three standard deviations exceeds 245 feet.

(e) Altimetry system error containment: Group aircraft for which application for type certification is made after April 9, 1997. To approve group aircraft for which application for type certification is made after April 9, 1997, the Administrator must find that the altimetry system error (ASE) is contained as follows:

(1) At the point in the full RVSM flight envelope where mean ASE reaches its largest absolute value, the absolute value may not exceed 80 feet.

(2) At the point in the full RVSM flight envelope where mean ASE plus three standard deviations reaches its largest absolute value, the absolute value may not exceed 200 feet.

(f) Altimetry system error containment: Nongroup aircraft. To approve a nongroup aircraft, the Administrator must find that the altimetry system error (ASE) is contained as follows:

(1) For each condition in the basic RVSM flight envelope, the largest combined absolute value for residual static source error plus the avionics error may not exceed 160 feet.

(2) For each condition in the full RVSM flight envelope, the largest combined absolute value for residual static source error plus the avionics error may not exceed 200 feet.

(g) Traffic Alert and Collision Avoidance System (TCAS) Compatibility With RVSM Operations: All aircraft. After March 31, 2002, unless otherwise authorized by the Administrator, if you operate an aircraft that is equipped with TCAS II in RVSM airspace, it must be a TCAS II that meets TSO C-119b (Version 7.0), or a later version.

(h) If the Administrator finds that the applicant's aircraft comply with this section, the Administrator notifies the applicant in writing.

Source: 14 CFR 91, Appendix G, Section 2

(a) Except as specified in Section 9 of this appendix, authority for an operator to conduct flight in airspace where RVSM is applied is issued in operations specifications, a Letter of Authorization, or management specifications issued under subpart K of this part, as appropriate. To issue an RVSM authorization under this section, the Administrator must find that the operator's aircraft have been approved in accordance with Section 2 of this appendix and the operator complies with this section.

(b) Except as specified in Section 9 of this appendix, an applicant seeking authorization to operate within RVSM airspace must apply in a form and manner prescribed by the Administrator. The application must include the following:

(1) [Reserved]

(2) For an applicant who operates under part 121 or 135 of this chapter or under subpart K of this part, initial and recurring pilot training requirements.

(3) Policies and procedures: An applicant who operates under part 121 or 135 of this chapter or under subpart K of this part must submit RVSM policies and procedures that will enable it to conduct RVSM operations safely.

(c) In a manner prescribed by the Administrator, an operator seeking authorization under this section must provide evidence that:

(1) It is capable to operate and maintain each aircraft or aircraft group for which it applies for approval to operate in RVSM airspace; and

(2) Each pilot has knowledge of RVSM requirements, policies, and procedures sufficient for the conduct of operations in RVSM airspace.

Source: 14 CFR 91, Appendix G, Section 3

Operators and pilots seeking to operate in RVSM airspace under the provisions of part 91 appendix G, section 9 are not required to apply for authorizations. The operator or pilot needs to ensure all applicable requirements in part 91 appendix G to operate in RVSM airspace are met. The operator or pilot should:

1. Determine the aircraft is RVSM-compliant (see Chapter 2, Aircraft Eligibility);
2. Ensure pilots are knowledgeable (see Chapter 3, Knowledge and Training);
3. Ensure the aircraft meets RVSM performance and the aircraft has been height monitored in accordance with paragraph 4.3 (see paragraph 4.3.5 when an operator is conducting the initial flight in RVSM airspace); and
4. Properly file a flight plan and understand the policies and procedures for the RVSM airspace in which the aircraft will operate.

Source: AC 91-85B, §4.1.1

Aircraft Equipped With Automatic Dependent Surveillance—Broadcast Out

An operator is authorized to conduct flight in airspace in which RVSM is applied provided:

(a) The aircraft is equipped with the following:

(1) Two operational independent altitude measurement systems.

(2) At least one automatic altitude control system that controls the aircraft altitude—

(i) Within a tolerance band of ±65 feet about an acquired altitude when the aircraft is operated in straight and level flight under nonturbulent, nongust conditions; or

(ii) Within a tolerance band of ±130 feet under nonturbulent, nongust conditions for aircraft for which application for type certification occurred on or before April 9, 1997, that are equipped with an automatic altitude control system with flight management/performance system inputs.

(3) An altitude alert system that signals an alert when the altitude displayed to the flightcrew deviates from the selected altitude by more than—

(i) ±300 feet for aircraft for which application for type certification was made on or before April 9, 1997; or

(ii) ±200 feet for aircraft for which application for type certification is made after April 9, 1997.

(4) A TCAS II that meets TSO C-119b (Version 7.0), or a later version, if equipped with TCAS II, unless otherwise authorized by the Administrator.

(5) Unless authorized by ATC or the foreign country where the aircraft is operated, an ADS-B Out system that meets the equipment performance requirements of §91.227 of this part. The aircraft must have its height-keeping performance monitored in a form and manner acceptable to the Administrator.

(b) The altimetry system error (ASE) of the aircraft does not exceed 200 feet when operating in RVSM airspace.

Source: 14 CFR 91, Appendix G, Section 9

RVSM aircraft must participate in altitude-keeping performance monitoring programs to ensure safe and efficient operations in RVSM airspace.

• Operators and pilots conducting RVSM operations under the provisions of part 91 appendix G, section 9 must ensure their aircraft meet the RVSM altitude-keeping performance monitoring requirements as described in Chapter 4, paragraph 4.3. Under these provisions, aircraft with qualified 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. All aircraft in an operator’s fleet must have been monitored within the previous 24 months and found to be in compliance with the performance requirement specified in part 91 appendix G, section 9(b).
• Operators conducting RVSM operations under the provision of part 91 appendix G, section 3 must meet the RVSM Minimum Monitoring Requirements (MMR) and have their aircraft monitored as specified in Appendix E, RVSM Altitude-Keeping Performance Monitoring When Operating With an RVSM OpSpec, MSpec, or LOA.

Source: AC 91-85B, §2.5.1

Flight Planning. During flight planning, the flightcrew and dispatchers, if applicable, should pay particular attention to conditions which may affect operation in RVSM airspace. These include, but may not be limited to:

1. Verifying the aircraft and operator meet RVSM requirements.
2. Annotating the flight plan to be filed with the Air Traffic Service Provider (ATSP) to show compliance for RVSM operations. The International Civil Aviation Organization (ICAO) flight plan, FAA Form 7233-4, Pre-Flight Pilot Checklist and International Flight Plan, Item 10, Equipment, should be annotated with the letter W for filing in RVSM airspace.
• When using FAA Form 7233-4, operators should ensure that the aircraft’s registration number (Reg/) is listed in Item 18 (Other Information), if different than that listed in Item 7 (Aircraft Identification).
• For exceptions to the use of FAA Form 7233-4, refer to the FAA AIM, Chapter 5, Air Traffic Procedures, for the proper flight codes

Note: An aircraft or operator not meeting the requirements for RVSM operations including an aircraft without operable RVSM equipment is referred to as non-RVSM. If either the flightcrew or aircraft do not meet the requirements for RVSM, the operator or dispatcher will not file the RVSM equipment code in the flight plan and follow the procedures for a non-RVSM status, including the appropriate pilot-air traffic control (ATC) phraseology in Table B-1, RVSM Phraseology.

3. Reported and forecast weather conditions on the route of flight.
4. Minimum equipment requirements pertaining to altitude-keeping systems.
5. Traffic Alert and Collision Avoidance System (TCAS) equipage. TCAS equipage requirements are contained in part 121, § 121.356; part 125, § 125.224; part 129, § 129.18; and part 135, § 135.180. Part 91 appendix G does not contain TCAS equipage requirements specific to RVSM; however, part 91 appendix G does require that aircraft equipped with TCAS II and flown in RVSM airspace be modified to incorporate TCAS II Version 7.0 or a later version.
6. If required for the specific aircraft Group, accounting for any aircraft operating restrictions related to RVSM airworthiness approval. (See Appendix A, RVSM Airworthiness Certification, paragraph A.10.1.3.)

Source: AC 91-85B, §B.3.1

Preflight Procedures. Accomplish the following actions during preflight:

1. Review maintenance logs and forms to ascertain the condition of equipment required for flight in the RVSM airspace. Ensure maintenance action has been taken to correct defects to required equipment.
2. During the external inspection of aircraft, pay particular attention to the condition of static sources, the condition of the fuselage skin near each static source, and any other component affecting altimetry system accuracy. (A qualified and authorized person other than the pilot (e.g., a Flight Engineer (FE) or maintenance personnel) may perform this check.)
3. Before takeoff:
• The aircraft altimeters should be set to the barometric pressure for local altimeter setting (QNH) and should display a known elevation (e.g., field elevation) within the limits specified in aircraft operating manuals. The difference between the known elevation and the elevation displayed on the altimeters should not exceed 75 ft.
• The two primary altimeters should also agree within limits specified by the aircraft operating manual/Airplane Flight Manual (AFM), as applicable. An alternative procedure using atmospheric pressure at aerodrome elevation (QFE) may also be used.

Note: Both checks should be an emphasis item for training materials.

4. Equipment required for flight in RVSM airspace should be operational, and indications of malfunction should be resolved.

Source: AC 91-85B, §B.3.2

Procedures Before RVSM Airspace Entry. If any of the required equipment fails prior to the aircraft entering RVSM airspace, the pilot should request a new clearance to avoid flight in this airspace. The following equipment must be operating normally at entry into RVSM airspace:

1. Two primary altitude measurement systems.
2. One automatic altitude control system.
3. One altitude alerting device.

Note: The operator or pilot should ascertain the requirement for an operational transponder and TCAS in each RVSM area where operations are intended.

Source: AC 91-85B, §B.3.3

In-Flight Procedures. Incorporate the following policies into flightcrew training and procedures, as applicable:

1. Flightcrews should comply with aircraft operating restrictions (if required for the specific aircraft Group) related to RVSM airworthiness approval. (See paragraph A.10.1.3.)
2. Place emphasis on promptly setting the sub-scale on all primary and standby altimeters to 29.92 inches of mercury (in Hg)/1013.25 hectopascals (hPa) when climbing through the transition altitude and rechecking for proper altimeter setting when reaching the initial cleared flight level (CFL).
3. In level cruise, it is essential the aircraft is flown at the CFL. This requires particular care is taken to ensure ATC clearances are fully understood and followed. Except in contingency or emergency situations, the aircraft should not intentionally depart from CFL without a positive clearance from ATC.
4. During cleared transition between FLs, the aircraft should not be allowed to overshoot or undershoot the CFL by more than 150 ft (45 m).

Note: It is recommended the level-off be accomplished using the altitude capture feature of the automatic altitude control system, if installed.

5. An automatic altitude control system must be operative and engaged during level cruise, except when circumstances such as the need to retrim the aircraft or turbulence require disengagement. In any event, adherence to cruise altitude should be done by reference to one of the two primary altimeters.
6. The altitude alerting system must be operational.
7. At cruise FL, the two primary altimeters should agree within 200 ft (60 m) or a lesser value if specified in the aircraft operating manual. (Failure to meet this condition will require that the altimetry system be reported as defective and notified to ATC.) Note the difference between the primary and standby altimeters for use in contingency situations.
8. At intervals of approximately 1 hour, make cross-checks between the primary altimeters and the standby altimeter.
1. The normal pilot scan of flight deck instruments should suffice for altimeter cross-checking on most flights.
2. When operating in surveillance airspace (Radar/Automatic Dependent Surveillance-Broadcast (ADS-B)), the initial altimeter cross-check should be performed after level-off.
3. In oceanic and remote continental (procedural) airspace, a cross-check should be performed and recorded in the vicinity of the point where oceanic and remote continental navigation begins (e.g., on coast out). The readings of the primary and standby altimeters should be recorded and available for use in contingency situations.
4. Some aircraft have automatic comparators that compare the two primary altimetry systems. The comparators include a monitoring, warning, and fault function. The faults may be recorded automatically by the system, but a record of the differences in the primary altimetry systems may not be easily derived.

Note: In oceanic and remote continental (procedural) airspace, even if the aircraft is equipped with automatic comparators, the crew should be recording the altimeter cross-checks for use in a contingency situation.

9. Normally, the altimetry system being used to control the aircraft should be selected to provide the input to the altitude-reporting transponder transmitting information to ATC.
10. If ATC notifies the pilot of an assigned altitude deviation (AAD) error equal to or exceeding 300 ft (90 m), then the pilot should take action to return to CFL as quickly as possible.

Source: AC 91-85B, §B.3.4

Contingency Procedures After Entering RVSM Airspace. The flightcrew, after realizing that they no longer can comply with RVSM requirements (aircraft system failure, weather, lost com, etc.), must request a new clearance from the controller/radio operator as soon as the situation allows. If a new clearance is not available or the nature of the emergency requires rapid action, the pilot should notify ATC of their action and contingency procedures. Operators should refer to the RVSM section of the AIM when experiencing abnormal situations and implementing contingency procedures. It is also the responsibility of the crew to notify ATC when the implementation of the contingency procedures is no longer required.

Source: AC 91-85B, §B.3.6

Postflight. In making maintenance logbook entries against malfunctions in altitude-keeping systems, the pilot should provide sufficient detail to enable maintenance to effectively troubleshoot and repair the system. The pilot should detail the actual defect and the crew action taken to try to isolate and rectify the fault. Note the following information when appropriate:

1. Primary and standby altimeter reading.
2. Altitude selector setting.
3. Subscale setting on altimeter.
4. Autopilot used to control the airplane and any differences when the alternate system was selected.
5. Differences in altimeter readings if alternate static ports selected.
6. Use of air-data computer (ADC) selector for fault diagnosis procedure.
7. Transponder selected to provide altitude information to ATC and any difference if alternate transponder or altitude source is manually selected.

Source: AC 91-85B, §B.3.7

Regular (hourly) cross-checks between the altimeters should be made, and a minimum of two RVSM MASPS-compliant systems must agree within 60 m (200 ft). Failure to meet this condition will require that the system be reported as defective and notified to ATC.

Source: ICAO Doc 9574, ¶5.1.1.(e)