AIM 8/15/19  1/30/20 tion and will also file the appropriate ICAO Flight Plan suffixes to indicate navigation and communica- tion capabilities. The equipment suffixes in TBL 5 − 1 − 3 are for use only in an FAA Flight Plan (FAA Form 7233 − 1). 2. Operators/aircraft that file ICAO flight plans that include flight in Domestic U.S. RVSM airspace must file “/W” in block 10 to indicate RVSM authorization. a. RVSM Mandate. If either the operator is not authorized for RVSM operations or the aircraft is not RVSM − compliant, the pilot will neither request nor accept a clearance into RVSM airspace unless: 1. The flight is conducted by a non − RVSM DOD, MEDEVAC, certification/development or foreign State (government) aircraft in accordance with Paragraph 4 − 6 − 10, Procedures for Accommo- dation of Non − RVSM Aircraft. e. Importance of Flight Plan Equipment Suffixes. The operator must file the appropriate equipment suffix in the equipment block of the FAA Flight Plan (FAA Form 7233 − 1) or the ICAO Flight Plan. The equipment suffix informs ATC: 2. The pilot intends to climb to or descend from FL 430 or above in accordance with Para- graph 4 − 6 − 11, Non − RVSM Aircraft Requesting Climb to and Descent from Flight Levels Above RVSM Airspace Without Intermediate Level Off. 3. An emergency situation exists. b. Basic RVSM Operating Practices and Procedures. AC 91 − 85 contains pilot practices and procedures for RVSM. Operators must incorporate applicable practices and procedures, as supplemented by the applicable paragraphs of this section, into operator training or pilot knowledge programs and operator documents containing RVSM operational policies. 1. Whether or not the operator and aircraft are authorized to fly in RVSM airspace. 2. The navigation and/or transponder capability of the aircraft (e.g., advanced RNAV, transponder with Mode C). f. Significant ATC uses of the flight plan equipment suffix information are: 1. To issue or deny clearance into RVSM airspace. 2. To apply a 2,000 foot vertical separation minimum in RVSM airspace to aircraft that are not authorized for RVSM, but are in one of the limited categories that the FAA has agreed to accommodate. (See Paragraphs 4 − 6 − 10, Procedures for Accommo- dation of Non RVSM Aircraft, and 4 − 6 − 11, Non − RVSM Aircraft Requesting Climb to and Descent from Flight Levels Above RVSM Airspace Without Intermediate Level Off, for policy on limited operation of unapproved aircraft in RVSM airspace). c. AC 91 − 85 contains practices and procedures for flight planning, preflight procedures at the aircraft, procedures prior to RVSM airspace entry, inflight (en route) procedures, contingency procedures and post flight. d. The following paragraphs either clarify or supplement AC 91 − 85 practices and procedures. 3. To determine if the aircraft has “Advanced RNAV” capabilities and can be cleared to fly procedures for which that capability is required. 1. The information and practices in this paragraph are provided to emphasize to pilots and controllers the importance of taking appropriate action in RVSM airspace when aircraft experience severe turbulence and/or MWA that is of sufficient magnitude to significantly affect altitude − keeping. g. Improperly changing an aircraft equipment suffix and/or adding “NON-RVSM” in the NOTES or REMARKS section (Field 18) while not removing the “W” from Field 10, will not provide air traffic control with the proper visual indicator necessary to detect Non-RVSM aircraft. To ensure information processes correctly for Non-RVSM aircraft, the “W” in Field 10 must be removed. Entry of information in the NOTES or REMARKS section (Field 18) will not affect the determination of RVSM capability and must not be used to indicate a flight is Non-RVSM. 2. Severe Turbulence. Severe turbulence causes large, abrupt changes in altitude and/or attitude usually accompanied by large variations in indicated airspeed. Aircraft may be momentarily out of control. Encounters with severe turbulence must 4 − 6 − 3 Operational Policy/Procedures for Reduced Vertical Separation Minimum (RVSM) in the Domestic U.S., Alaska, Offshore Airspace and the San Juan FIR a. Introduction/Explanation 4 − 6 − 6. Guidance on Severe Turbulence and Mountain Wave Activity (MWA) 4 − 6 − 5. Pilot RVSM Operating Practices and Procedures