Minimum Obstruction Clearance Altitude(MOCA)
Definition
The lowest altitude on an airway that provides required obstacle clearance. Navigation signal reception is guaranteed only within 22 nautical miles of a VOR. Below MEA but provides obstacle clearance.
Why Minimum Obstruction Clearance Altitude Matters for Pilots
Navigation concepts like Minimum Obstruction Clearance Altitude are tested on instrument rating exams and are essential for safe cross-country flying. Whether you are planning a VFR flight or navigating under IFR, a solid understanding of Minimum Obstruction Clearance Altitude ensures you can find your way accurately and efficiently.
Exam Tip
This concept is commonly tested in navigation-related questions on FAA and EASA exams. Make sure you can explain Minimum Obstruction Clearance Altitude in your own words for the oral exam. Practice applying this concept to real-world scenarios, not just memorizing the definition.
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