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Bascuela
11-15-2006, 02:40 PM
Scenario:
An airports DP or ODP will take a pilot to an enroute fix. Sometimes there is a minimum altitude upon crossing that fix or even a climbing holding pattern at the fix to continue on course. It was always my understanding that if a pilot was to leave that fix and go off published route, then the pilot would need to be at least at the MORA (OROCA). Sometimes the MORA can be very high because of nearby terrain in the grid.

Question:
Can a pilot leave the published route BELOW the MORA still climbing to cruise altitude?

My take has always been that you need to be at the MORA if operating off route as per 91.177 (a)(1). However, when I continue to read the regulation I’m not sure what paragraph two is talking about. Can I break out my VFR sectional, draw my course and measure 1000’ (or 2000’) above the highest obstacle and then use that as my “MORA”? From an obstacle clearance standpoint it works, but is that legal? Also, 91.177(a)(2) “….If no applicable minimum altitude is prescribed…” When would this apply?
- Thanks :)


rickair7777
11-15-2006, 05:22 PM
Scenario:
An airports DP or ODP will take a pilot to an enroute fix. Sometimes there is a minimum altitude upon crossing that fix or even a climbing holding pattern at the fix to continue on course. It was always my understanding that if a pilot was to leave that fix and go off published route, then the pilot would need to be at least at the MORA (OROCA). Sometimes the MORA can be very high because of nearby terrain in the grid.

Question:
Can a pilot leave the published route BELOW the MORA still climbing to cruise altitude?

My take has always been that you need to be at the MORA if operating off route as per 91.177 (a)(1). However, when I continue to read the regulation I’m not sure what paragraph two is talking about. Can I break out my VFR sectional, draw my course and measure 1000’ (or 2000’) above the highest obstacle and then use that as my “MORA”? From an obstacle clearance standpoint it works, but is that legal? Also, 91.177(a)(2) “….If no applicable minimum altitude is prescribed…” When would this apply?
- Thanks :)

I'm pretty sure of this...

The grid MORA/MORA is published to provide terrain clearance info to an aircraft that is in some sort of trouble.

It is not regulatory, therefore the 91.177 rules should apply (ie you can use the 1000/2000/4NM thing). Realistically, you would have to map this stuff out prior to departure if you intend to use off-airway navigation. It would get real busy if you try to do it enroute with a pencil and ruler!

In some areas, you might be able to fly off-route by just using the grid mora as your MEA/MOCA, but the data on which it is based is not always known to be 100% accurate...

For departure, I would just comply with a DP/ODP as published. Hold to gain altitude if you need to.