AIM ¶ 4-7-1 — Gulf RNP Lateral Separation
AIM 4-7-1 explains 50 NM lateral separation in the Gulf of America for RNP 10/RNP 4 aircraft. Key facts for pilot oral exams and checkrides.
AIM 4-7-1 describes how ATC applies 50 NM lateral separation between aircraft authorized for RNP 10 or RNP 4 when operating over the Gulf of America. This reduced spacing lets more airplanes fly optimum routes and altitudes in oceanic airspace where radar coverage is limited.
The 50 NM lateral separation may be used in:
- Houston Oceanic CTA/FIR
- Gulf of America portion of the Miami Oceanic CTA/FIR
- Monterrey CTA
- Merida High CTA within the Mexico CTA/FIR
To qualify, your flight plan must indicate PBN approval along with RNP 10 or RNP 4. Aircraft without RNP 10/4 capability are spaced farther apart:
- At least 90 NM in Miami Oceanic CTA/FIR
- At least 100 NM in Houston, Monterrey, and Merida CTA/FIRs
The 50 NM standard does not apply on routes defined by ground navaids or on Gulf RNAV Routes Q100, Q102, or Q105. Operators can find planning details and RNP authorization guidance in the FAA's West Atlantic, Gulf of America, and Caribbean Resource Guide. This is a recommended/operational policy, not a regulatory mandate on pilots.