Using the MOCA?

It appers that the FAA revised 91.177 a couple years back to account for GPS usage of altitudes below the MEA (but above the MOCA) - see below. Has anyone successfully negotiated with ATC to cruise between the MOCA and MEA? How difficult is it? Out west, not having to go above 12,500 in mountinous terrain would be useful.

I imagine that radar and communications coverage could be an issue at the MOCA, but then again, neither of these are guaranteed at the MEA either…


FAR 91.177 now states:

a) Operation of aircraft at minimum altitudes. Except when necessary for takeoff or landing, no person may operate an aircraft under IFR below–
(1) The applicable minimum altitudes prescribed in parts 95 and 97 of this chapter. However, if both a MEA and a MOCA are prescribed for a particular route or route segment, a **person may operate an aircraft below the MEA down to, but not below, the MOCA, provided the applicable navigation signals are available. **For aircraft using VOR for navigation, this applies only when the aircraft is within 22 nautical miles of that VOR (based on the reasonable estimate by the pilot operating the aircraft of that distance);

As I understand it, ATC really doesn’t care. All they care is that you remain within radar coverage or on airways with reporting points.

All of my flights are GPS direct, so I select MOCA when I can. (Kinda funny I was taught the term OROCA rather then MOCA)

Unfortunately, when I go from KMBO to KEKY, the MOCA is lower then radar coverage so I fly higher so I can get GPS direct.

One thing for sure the way I read it, the FARS you quote sure supports what you think.

MOCA is if you’re in the airway. OROCO is if you’re off the airway.

Gotchya. Probably one of the quite a few questions I missed on the written :slight_smile:

I just look for the big numbers on the gridded boxes on the enroute chart to figure out manually the minimum altitude or just use the AOPA flight planner that puts the OROCA and MOCA in the nav log.

On a related note to the question, while I wouldn’t advise this for hard IFR, per AIM 4-4-9 … m0404.html

we can accept clearances below the minimums but then the separation becomes the responsibility of the pilot.

On the opposite end of the coin, I definitely don’t have to worry about dstreufe problem of 12.5 in my Sundowner as by the time I crawl up there (more like IF I can), it will be time to descend :laughing: