4/20/23 

AIM 

NOTE

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The unique ADS

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B architecture in the Gulf of Mexico depends upon reception of an aircraft’s Mode C in addition to the other 

message elements described in 14 CFR 91.227. Flight crews must be made aware that loss of Mode C also means that ATC 

will not receive the aircraft’s ADS

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B signal. 

5. 

FAA/AIS publishes the grid system waypoints on the IFR Gulf of Mexico Vertical Flight Reference 

Chart. A commercial equivalent is also available. The chart is updated annually and is available from an FAA 

approved print provider or FAA directly, website address: http://www.faa.gov/air_traffic/flight_info/aeronav. 

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5.  Departure Procedures 

a. 

When departing from a location on a point

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in

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space (PinS) SID with a visual segment indicated and the 

departure instruction describes the visual segment the aircraft must cross the initial departure fix (IDF) outbound 

at

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or

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above the altitude depicted on the chart. The helicopter will initially establish a hover at or above the 

heliport crossing height (HCH) specified on the chart. The HCH specifies a minimum hover height to begin the 

climb to assist in avoiding obstacles. The helicopter will leave the departure location on the published outbound 

heading/course specified, climbing at least 400 ft/per NM (or as depicted on the chart), remaining clear of 

clouds, crossing at or above the IDF altitude specified, prior to proceeding outbound on the 

procedure. For example the chart may include these instructions: “Hover at 15 ft AGL, then climb on track 005, 

remaining clear of clouds, to cross PAWLY at or above 700.” 

b. 

When flying a PinS SID procedure containing a segment with instructions to “proceed VFR,” the pilot 

must keep the aircraft clear of the clouds and cross the IDF outbound at or above the altitude depicted. Departure 

procedures that support multiple departure locations will have a Proceed VFR segment leading to the 

IDF. The chart will provide a bearing and distance to the IDF from the heliport. That bearing and distance are 

for pilot orientation purposes only and are not a required  procedure track. The helicopter will leave the departure 

location via pilot navigation in order to align with the departure route and comply with the altitude specified at 

the IDF.  For example, the chart may include these instructions: “VFR Climb to WEBBB, Cross WEBBB at or 

above 800.” 

c. 

Once the aircraft reaches the IDF, the aircraft should proceed out the described route as specified on the 

chart, crossing each consecutive fix at or above the indicated altitude(s) until reaching the end of the departure or 

as directed by ATC. 

Helicopter IFR Operations 

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