VFR MOCA and MEA

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Jason608

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Jason608
I started studying for IFR and while reading the Low Enroute charts I see the MEA (Min. Enroute Alt.) and MOCA (Min. Obstruction Clearance Altitude) for Victor Airways. I understand MEA and MOCA designate the altitude and guarantee frequencies but also provide the safe altitude to fly.

Why isn't there a labeled safe altitude to fly on Victor Airways for VFR?
 
Vfr you're visual, you can see towers and mountains. Ifr you can not. You're also restricted in how much altitude you have and course deviation. Vfr you go where you want when you want.

Sent from my LGLS991 using Tapatalk
 
True, but it would be reassuring to have a recommended altitude to fly VFR on Victor Airways.
 
Jason608 said:
I started studying for IFR and while reading the Low Enroute charts I see the MEA (Min. Enroute Alt.) and MOCA (Min. Obstruction Clearance Altitude) for Victor Airways. I understand MEA and MOCA designate the altitude and guarantee frequencies but also provide the safe altitude to fly.

Why isn't there a labeled safe altitude to fly on Victor Airways for VFR?
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The MEA and MOCA are just as safe for VFR operationa as they are for IFR operations.
 
Why would one want to fly on an airway when VFR? Heck, even IFR I have to have a reason to be on an airway. Better to avoid congregations of other aircraft when responsible for your own traffic avoidance.
 
Jason608 said:
True, but it would be reassuring to have a recommended altitude to fly VFR on Victor Airways.
Click to expand...

The recommended altitude is NOT on an IFR altitude.

An MRA might be nice on VFR charts, but if you can't maintain visual separation from the ground, you really shouldn't be flying in that.

Honestly, VFR charts suffer from excessive detail. IMO, they shouldn't have victor airways at all. There is a lot less stuff on IFR charts. One thing that would be REALLY useful is TPA, but that will add a lot of clutter in some places.
 
Victor airways, indeed the entire IFR system, is designed with the assumption that you are in the clouds. The minimum safe altitude VFR is whatever the PIC wants it to be within the few boundaries set by the FARs. When VFR you are presumably able to see and avoid terrain, obstacles and traffic so it's up to the PIC.

But IFR the FAA has set up certain standards that the follow in creating those airways (for insomniacs, download the Instrument Procedures Handbook). If you're on an airway VFR it is purely by choice and for convenience, but if you follow the minimum IFR (MEA, MRA, MOCA, even OROCA) altitudes they will keep you out of the rocks.
 
MRA doesn't keep you out of the rocks. It keeps you on course and allows you to identify intersections if you're not GPS equipped.
 
The CFIs I worked with pushed using Airways for my XCs.
 
Jason608 said:
The CFIs I worked with pushed using Airways for my XCs.
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Then just use the hemisphere rule for VFR altitude as there is no published VFR altitude for Victor airways.
 
Jason608 said:
The CFIs I worked with pushed using Airways for my XCs.
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Really?

There can be a lot of traffic around VORs at VFR altitudes above the MEA. Much of it with view limiting devices and distracted instructors in use.

I try specifically to avoid VORs in VMC, except below the MEA.
 
The key word for VFR is visual ,if you can't see the terrain you shouldn't be VFR.
 
frfly172 said:
The key word for VFR is visual ,if you can't see the terrain you shouldn't be VFR.
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Well, technically, you can be above a layer and not see terrain.

But you can still see any cumulogranite poking up above the layer and avoid it.
 
Jason608 said:
True, but it would be reassuring to have a recommended altitude to fly VFR on Victor Airways.
Click to expand...

Not sure I understand how it would be reassuring, but you can buy or get an out-of-date chart. Lots of planes can't make the altitudes required for IFR in the mountains. 2000' above west of me takes 16000'. Much of my enjoyment comes from seeing thing low and up close.
 
I am only VFR but isn't that what the MEF (maximum elevation figure) is in each quadrant of the VFR chart? I typically assume if I am at least 1k feet above that number I'm doing OK. It doesn't relate to airways though. Just the while quadrant.
 
MAKG1 said:
MRA doesn't keep you out of the rocks. It keeps you on course and allows you to identify intersections if you're not GPS equipped.
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Correct, but just to clarify, isn't MRA a maximum altitude for reception? If not MRA, one of them is. Too high and you get interference from other navaids with like frequencies.
 
Jason608 said:
The CFIs I worked with pushed using Airways for my XCs.
Click to expand...

Is this to teach you VOR navigation and you only have one radio? I can see using airways going through some mountainous terrain, otherwise direct to and grab flight following.
 
Jason608 said:
I started studying for IFR and while reading the Low Enroute charts I see the MEA (Min. Enroute Alt.) and MOCA (Min. Obstruction Clearance Altitude) for Victor Airways. I understand MEA and MOCA designate the altitude and guarantee frequencies but also provide the safe altitude to fly.

Why isn't there a labeled safe altitude to fly on Victor Airways for VFR?
Click to expand...

Because Victor Airways are not designed for VFR use. Doesn't mean you can't fly on them VFR, It's just not what they are there for. Many Victor Airways are depicted on Sectional Charts. MEA's and MOCA's aren't published on them. It's not what they are designed for. In kind of a left handed way, there is a "labeled safe altitude to fly on Victor Airways for VFR". They call them MEA's and MOCA's. Don't forget the even and odd plus 500 thing though.
 
MAKG1 said:
Then use the IFR charts.
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I assumed that was what he was getting at, but I guess it was ambiguous. In any case, staying on airways above the IFR MEA is an excellent strategy for night VFR.

If you can't see the terrain, the VFR chart doesn't help.
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Why not? If the pilot doesn't want to examine them in detail for the elevations of terrain and obstructions, 1000 feet above the printed maximum elevation figures, or 2000 feet in mountainous areas, would be an effective approach. Of course, one has to draw a course line on the chart (or stay on airways), and be sure to navigate that course, in order for either of those methods to work.
 
MAKG1 said:
Then use the IFR charts. If you can't see the terrain, the VFR chart doesn't help.
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Not sure about today's world of electronic charts, but IFR charts at one point a few years back were expensive. A cost burden private pilots did not take on, especially went they weren't even trained to read them.
 
Kritchlow said:
Not sure about today's world of electronic charts, but IFR charts at one point a few years back were expensive. A cost burden private pilots did not take on, especially went they weren't even trained to read them.
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With all the EFBs out there you can get every chart for $75 a year
 
Kritchlow said:
Not sure about today's world of electronic charts, but IFR charts at one point a few years back were expensive. A cost burden private pilots did not take on, especially went they weren't even trained to read them.
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An IFR low chart on paper cost about half what a sectional does.
 
MAKG1 said:
MRA doesn't keep you out of the rocks. It keeps you on course and allows you to identify intersections if you're not GPS equipped.
Click to expand...

Is there someplace where MRA is lower than MOCA?
 
Kritchlow said:
Correct, but just to clarify, isn't MRA a maximum altitude for reception? If not MRA, one of them is. Too high and you get interference from other navaids with like frequencies.
Click to expand...

Isn't it minimum reception altitude?
 
MAKG1 said:
An IFR low chart on paper cost about half what a sectional does.
Click to expand...

Perhaps that's true, but at one point you had to buy a subscription set of jepps. Not sure how the old NOS charts were sold. The smallest Jepp subscription was "northeast", and was quite expensive. I do realize that's changed.
 
PPC1052 said:
Isn't it minimum reception altitude?
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Don't think so. I believe it's a maximum due to like frequencies that can start to become line of sight. As always, I could be wrong.

MEA guarantees both terrain and reception. MOCA promises terrain and reception within 22nm I believe. Really digging back many years for that one..
 
MAKG1 said:
MRA doesn't keep you out of the rocks. It keeps you on course and allows you to identify intersections if you're not GPS equipped.
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The first time you used MRA I assumed it was a typo, that you meant MEA. The MEA keeps you out of the rocks and an MRA will always be higher than the MEA so flight at the MRA will also keep you out of the rocks.
 
Kritchlow said:
Correct, but just to clarify, isn't MRA a maximum altitude for reception? If not MRA, one of them is. Too high and you get interference from other navaids with like frequencies.
Click to expand...

No, MRA is Minimum Reception Altitude. It is the lowest altitude at which the non-tracked NAVAID forming an intersection can be reliably received.
 
roncachamp said:
No, MRA is Minimum Reception Altitude. It is the lowest altitude at which the non-tracked NAVAID forming an intersection can be reliably received.
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You know, I wasn't completely sure about that.
That said, I believe there is an acronym for the max also. I *may* be getting it confused with Mexican nomenclature.
 
PPC1052 said:
Is there someplace where MRA is lower than MOCA?
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If there is it is in error. That would mean the non-tracked NAVAID forming the intersection can be received at altitudes lower than can be flown on the airway. That's not a problem.
 
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