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Operational Policy/Procedures for Reduced Vertical Separation Minimum (RVSM) in the
Domestic U.S., Alaska, Offshore Airspace and the San Juan FIR


−6−9. Contingency Actions: Weather

Encounters and Aircraft System Failures
that Occur After Entry into RVSM Airspace


−6−2 provides pilot guidance on actions to

take under certain conditions of aircraft system

failure that occur after entry into RVSM airspace
and weather encounters. It also describes the
expected ATC controller actions in these situations. It
is recognized that the pilot and controller will use
judgment to determine the action most appropriate to
any given situation.



Contingency Actions:  Weather Encounters and Aircraft System Failures that Occur After Entry into RVSM


Initial Pilot Actions in Contingency Situations

Initial pilot actions when unable to maintain flight level (FL) or unsure of aircraft altitude



Notify ATC and request assistance as detailed below. 

Maintain cleared flight level, to the extent possible, while evaluating the situation.

Watch for conflicting traffic both visually and by reference to TCAS, if equipped.

Alert nearby aircraft by illuminating exterior lights (commensurate with aircraft limitations).

Severe Turbulence and/or Mountain Wave Activity (MWA) Induced 

Altitude Deviations of Approximately 200 feet

Pilot will:

Controller will:

When experiencing severe turbulence and/or
MWA induced altitude deviations of
approximately 200 feet or greater, pilot will
contact ATC and state “Unable RVSM Due (state
reason)” (e.g., turbulence, mountain wave)

If not issued by the controller, request vector
clear of traffic at adjacent FLs

If desired, request FL change or re−route

Report location and magnitude of turbulence or

Vector aircraft to avoid merging target with
traffic at adjacent flight levels, traffic permitting

Advise pilot of conflicting traffic

Issue FL change or re−route, traffic permitting

Issue PIREP to other aircraft

See Paragraph 4

−6−6, Guidance on Severe

Turbulence and Mountain Wave Activity (MWA) for
detailed guidance.

Paragraph 4

−6−6 explains “traffic permitting.”