AIM

4/3/14

4−7−4

Operational Policy/Procedures for the Gulf of Mexico 50 NM Lateral Separation Initiative

4

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7

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8. Flight Planning Requirements

Operators must make ICAO flight plan annotations

in accordance with this paragraph and, if applicable,

paragraph 4−7−5, Provisions for Accommodation of

NonRNP10 Aircraft (Aircraft Not Authorized RNP

10 or RNP 4).

a.

ICAO Flight Plan Requirement. ICAO flight

plans must be filed for operation on oceanic routes

and areas in the Houston Oceanic CTA/FIR, the Gulf

of Mexico portion of the Miami CTA/FIR, the

Monterrey CTA and Merida High CTA.

b.

To inform ATC that they have obtained RNP 10

or RNP 4 authorization and are eligible for 50 NM

lateral separation, operators must:

1.

Annotate ICAO Flight Plan Item 10

(Equipment) with the letters “R” and “Z”, and

2.

Annotate Item 18 (Other Information) with,

as appropriate, “NAV/RNP10” or “NAV/RNP4” (no

space between letters and numbers).

NOTE

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1. See paragraph 4

−7−8e. It provides recommended

filing practices for domestic U.S. RNAV operations and
filing with EUROCONTROL.

2. On the ICAO Flight Plan, the letter “R” in Item 10
indicates that the aircraft will maintain the appropriate
RNP navigation specification for the entire flight through
airspace where RNP is prescribed. Letter “Z” in Item 10
indicates that information explaining aircraft navigation
and/or communication capability is found in Item 18.

c.

50 NM lateral separation will only be applied to

operators/aircraft that annotate the ICAO flight plan

in accordance with this policy. (See 4−7−8b.)

d.

Operators that have not obtained RNP 10 or

RNP 4 authorization must not annotate ICAO flight

plan Item 18 (Other information) with “NAV/

RNP10” or “NAV/RNP4”, but must follow the

practices detailed in paragraph 4−7−5.

e.

Recommendation for Filing to Show Domestic

U.S. RNAV and Oceanic RNP Capabilities.

1. Explanation.

 The FAA program to enhance

operators’ capability to communicate their domestic

U.S. RNAV capabilities to ATC has been in place for

over three years. It requires an entry following the

NAV/ indicator in Item 18 of the ICAO flight plan.

The initiative has provisions for including RNAV

capabilities for departure (“D”), enroute (“E”) and

arrival (“A”) with RNAV accuracy values. Detailed

instructions are available on the following web page:

http://www.faa.gov/about/office_org/headquar-

ters_offices/ato/service_units/enroute/flight_plan_fi

ling/

EXAMPLE

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An example Item 18 entry is: NAV/RNVD1E2A1.  The
characters in the example indicate RNAV 1 and RNAV 2
accuracy.

2. Recommendation.

 It is recommended that

operators provide their RNAV capability for

domestic U.S. and capabilities for oceanic operations

(RNP 10 or RNP 4) by filing: “NAV/”, then the

domestic U.S. alphanumeric sequence, then a

mandatory space and then “RNP10” or “RNP4”, as

appropriate.

EXAMPLE

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“NAV/RNVD1E2A1  RNP10”

3. Multiple NAV/ Entries.

 Operators should be

aware that if they make multiple “NAV/” entries in a

flight plan filed with EUROCONTROL, only the last

“NAV/” entry will be forwarded to the next ATC

facility. For example, if “NAV/RNVD1E2A1” and

“NAV/RNP10” are entered, only “NAV/RNP10” will

be forwarded. Multiple “NAV/” entries should,

therefore, be consolidated following a single “NAV/”

indicator.

4. Recommendation.

 Item 18 entries made in

accordance with paragraph 4-7-8 e. 2. above will

limit the number of characters needed to show

domestic U.S. RNAV and oceanic RNP capabilities

and mitigate the chance that one or the other will not

be forwarded for use by FAA domestic and oceanic

automation systems.

f. Implementation of ICAO Doc 4444, Revised

Appendix 2 (Flight  Plan).

 ICAO Doc 4444,

Amendment 1 revises Appendix 2 (Flight Plan).

Specifically, Amendment 1 revises the flight plan

annotations in Item 10 (Equipment) and Item 18

(Other Information) that show aircraft communica-

tions, navigation and surveillance capabilities. The

new Appendix 2 flight plan annotations will be

required on 15 November 2012. The following

Websites provide information on implementation

planning:

1.

FAA Website: http://www.faa.gov/go/

fpl2012.