IMC vs. VMC

Oh? What circumstances prohibit the legal operation of an aircraft under Instrument Flight Rules in Class G airspace without an IFR flight plan or clearance?



It isn't possible to operate under Instrument Flight Rules in the G-space between the surface and the overlying E-space above an airport without an ATC clearance. That would put the operation within 700 feet of the surface in violation of FAR 91.177.
I think Administrator v. Murphy also said you can't do it in "G below 1,200" too, as it's almost impossible to remain legal.

Maintaining 1,000 above the highest terrain or obstacle withing 4nm of your course, with the fact that towers of 199' can be there uncharted gives you ~1 foot of wiggle room...:hairraise:

That all but prohibits IFR in G without clearance to enter overlying controlled outside of the G->14,500.
 
I think Administrator v. Murphy also said you can't do it in "G below 1,200" too, as it's almost impossible to remain legal.

Maintaining 1,000 above the highest terrain or obstacle withing 4nm of your course, with the fact that towers of 199' can be there uncharted gives you ~1 foot of wiggle room...:hairraise:

1,000 feet above the highest obstacle within a horizontal distance of 4 nautical miles from the course to be flown isn't enough. You have to comply with all applicable Instrument Flight Rules. FAR 91.179 doesn't permit nap of the Earth flying to maintain that one foot of wiggle room, you have to maintain a cardinal altitude correct for direction of flight. Relief from the hemispheric rule within 3000' of the surface is limited to VFR operations.
 
Oh? What circumstances prohibit the legal operation of an aircraft under Instrument Flight Rules in Class G airspace without an IFR flight plan or clearance?
The circumstances under which Mr. Murphy was operating.

It isn't possible to operate under Instrument Flight Rules in the G-space between the surface and the overlying E-space above an airport without an ATC clearance. That would put the operation within 700 feet of the surface in violation of FAR 91.177.
I suggest re-reading the first sentence of 91.177 -- the part about "except when necessary for takeoff and landing..." Further, 91.177 says nothing about the presence or absence of an ATC clearance. Or are you suggesting that an ATC clearance can somehow override the requirements of 91.177? I think not. The FAA's contention in Murphy was limited to airports where instrument approach/departures under ATC clearances were in progress. In that Boondock, Montana, case, no such conflict would exist, since ATC doesn't clear people for departures/approaches in such cases.
 
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1,000 feet above the highest obstacle within a horizontal distance of 4 nautical miles from the course to be flown isn't enough. You have to comply with all applicable Instrument Flight Rules. FAR 91.179 doesn't permit nap of the Earth flying to maintain that one foot of wiggle room, you have to maintain a cardinal altitude correct for direction of flight. Relief from the hemispheric rule within 3000' of the surface is limited to VFR operations.

Well, part of my nap of the Earth flying would involve bobbing up and down and turning constantly, making 91.179(b) inapplicable, which is only applicable in level flight (so while climbing and descending I'm good) and excepts "while turning".:cornut:

Oh, and where is the uncontrolled airspace at flight level 290 and above contemplated by 91.179(b)(3)?? I know there's a bit above 18,000 up in Alaska, but above 290?
 
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The circumstances under which Mr. Murphy was operating.

Mr. Murphy was not operating legally.

I suggest re-reading the first sentence of 91.177 -- the part about "except when necessary for takeoff and landing..."
So I can legally operate under IFR in IMC within 700' of the surface if I limit my operations to takeoffs and landings?

Further, 91.177 says nothing about the presence or absence of an ATC clearance. Or are you suggesting that an ATC clearance can somehow override the requirements of 91.177?
How do you comply with 91.177 where Class E airspace begins at 700' AGL without an ATC clearance?

I think not.
Yes, I know.
 
Mr. Murphy was not operating legally.
Good -- we agree.

So I can legally operate under IFR in IMC within 700' of the surface if I limit my operations to takeoffs and landings?
No.

How do you comply with 91.177 where Class E airspace begins at 700' AGL without an ATC clearance?
You can't.

Now, go back and read what I originally said, and you'll see that it is consistent with what I wrote in this post.
 
Then what point were you trying to make?
The point that it's not always illegal or always legal to fly IFR in IMC in uncontrolled airspace without a flight plan or clearance. It's all situations.
Correct! See, you can learn if you try.
Since I have not changed my position on this issue, I don't see how you can say I've learned anything from you on the point. I'll say it one more time: Depending on the circumstances, it's sometimes possible to operate IFR in Class G airspace legally without either a flight plan or a clearance. The Murphy case shows one situation where it's not legal. There are other situations where it is. Underneath the 700-foot floor of E-space over an airport with instrument approaches is not one of them. Out in the big brown areas on the L-charts where the floor of E-controlled airspace is 14,500 and you can fly from Point A to Point B at a 91.177-legal altitude without underflying any published instrument approaches or crossing any controlled airspace and you'll be VMC before you descend below the 91.177 minimum altitude at your destination (so you don't have to make an instrument letdown) appears to be one where it's legal.
 
The circumstances under which Mr. Murphy was operating.

I suggest re-reading the first sentence of 91.177 -- the part about "except when necessary for takeoff and landing..." Further, 91.177 says nothing about the presence or absence of an ATC clearance. Or are you suggesting that an ATC clearance can somehow override the requirements of 91.177? I think not. The FAA's contention in Murphy was limited to airports where instrument approach/departures under ATC clearances were in progress. In that Boondock, Montana, case, no such conflict would exist, since ATC doesn't clear people for departures/approaches in such cases.


Whether it is legal or not in Montana, it still may not be wise.

http://www.bozemandailychronicle.com/news/article_c52e65ea-b499-11df-a71e-001cc4c03286.html
 
The point that it's not always illegal or always legal to fly IFR in IMC in uncontrolled airspace without a flight plan or clearance. It's all situations.

I see. You felt a need to say what went without saying.

Since I have not changed my position on this issue, I don't see how you can say I've learned anything from you on the point.
What were you trying to say when you wrote:

I suggest re-reading the first sentence of 91.177 -- the part about "except when necessary for takeoff and landing..." Further, 91.177 says nothing about the presence or absence of an ATC clearance. Or are you suggesting that an ATC clearance can somehow override the requirements of 91.177? I think not.
I'll say it one more time: Depending on the circumstances, it's sometimes possible to operate IFR in Class G airspace legally without either a flight plan or a clearance.
In other words, one can legally operate under Instrument Flight Rules without an IFR flight plan or clearance in Class G airspace.

The Murphy case shows one situation where it's not legal. There are other situations where it is. Underneath the 700-foot floor of E-space over an airport with instrument approaches is not one of them. Out in the big brown areas on the L-charts where the floor of E-controlled airspace is 14,500 and you can fly from Point A to Point B at a 91.177-legal altitude without underflying any published instrument approaches or crossing any controlled airspace and you'll be VMC before you descend below the 91.177 minimum altitude at your destination (so you don't have to make an instrument letdown) appears to be one where it's legal.
It's always legal to operate in IMC in Class G airspace when it can be done in accordance with all applicable FARs.
 
This gets so old. Does anyone actually read this stuff? It seems some of those that do the writing don't even read the post they're bickering about...
 
I think the long and short is that both Ron Levy and Stephen McNicoll are right.
 
In other words, one can legally operate under Instrument Flight Rules without an IFR flight plan or clearance in Class G airspace.
That statement is not true without qualification.
It's always legal to operate in IMC in Class G airspace when it can be done in accordance with all applicable FARs.
:confused: Sounds like you're saying it's legal to do anything you want as long as it's done legally. I prefer to provide a more useful contribution to the understanding of the issues involved in operating legally.
 
That statement is not true without qualification.

Don't be silly. The statement is true if there are any conditions under which one can legally operate under Instrument Flight Rules without an IFR flight plan or clearance in Class G airspace.

Sounds like you're saying it's legal to do anything you want as long as it's done legally.
Do you dispute that?

I prefer to provide a more useful contribution to the understanding of the issues involved in operating legally.
It appears you simply prefer to provide as many "contributions" as possible, whether or not you have anything useful to add.
 
Hey - I'll get back to the original question:

Ok - this is one of those questions that I've always had, but forgot the question whenever I was around anyone that could answer. It just came back to me in the shower.

On an IFR flight plan, in VMC, the pilot is responsible for See and Avoid. On an IFR flight plan in IMC, ATC is responsible for separation. How can anyone really know if you are IMC or VMC?

Here's my story of see-and-avoid, ATC separation, IMC, and VMC:

I was in IMC with my CFI during a flight review - I'm a VFR-only guy, we did actual instead of hoodwork that day. There was a thick layer that we stayed inside. Just beyond the boundary it was CAVU.

It's also the only time I've personally heard a controller get a high-pitched voice and say "Traffic Alert!!". We were in IMC, but another plane was in VMC and we were both heading for the same spot. My CFI yanked us into a steep turn, we popped out the side of the clouds, I saw the other airplane, then we popped back in. If he was VFR, he should have been been maintaining horizontal cloud clearance. Maybe he was, but that buffer would have been eaten up really quickly if we hadn't been warned.
 
To further the trains of thought... IF one can legally operate IMC in Class G airspace, why would you necessarily play by IFR. If you are flying in Class G, wouldn't you know the area well enough to do it safely? If not, well...that implies you will not play by, or there is no need to play by IFR and safety be dammed. Comments welcomed.

Noah Werka
 
To further the trains of thought... IF one can legally operate IMC in Class G airspace, why would you necessarily play by IFR. If you are flying in Class G, wouldn't you know the area well enough to do it safely? If not, well...that implies you will not play by, or there is no need to play by IFR and safety be dammed. Comments welcomed.

Noah Werka

A lot depends on whether the pilot cares whether he lives or dies.
 
Moderators,
I'd hereby like to make a request for an icon for "urinating wars" that can be applied to a thread. Thanks!
 
To further the trains of thought... IF one can legally operate IMC in Class G airspace, why would you necessarily play by IFR. If you are flying in Class G, wouldn't you know the area well enough to do it safely? If not, well...that implies you will not play by, or there is no need to play by IFR and safety be dammed. Comments welcomed.

Noah Werka

Legally speaking, you are required to operate under IFR rules anytime you are in conditions that are not VFR/SVFR. Essentially, you are operating under IFR rules anytime you are either (a) Operating under an IFR clearance/flight plan and/or (b) In conditions below VMC.

The IFR rules specifically have minimum safe altitudes, and address hemispheric altitudes specifically for uncontrolled airspace, which is exclusively Class G.
 
This gets so old. Does anyone actually read this stuff? It seems some of those that do the writing don't even read the post they're bickering about...

Moderators,
I'd hereby like to make a request for an icon for "urinating wars" that can be applied to a thread. Thanks!
This is why it would be nice to have that ignore thread feature. You could just put these types of threads on ignore and they cease to exist in the way that if a tree fall in the forest and only two people are there, they can argue if they heard it, vein.
 
This is why it would be nice to have that ignore thread feature. You could just put these types of threads on ignore and they cease to exist in the way that if a tree fall in the forest and only two people are there, they can argue if they heard it, vein.

Why not just skip the threads you're not interested in?
 
Moderators,
I'd hereby like to make a request for an icon for "urinating wars" that can be applied to a thread. Thanks!

Love it!!!

images


Or this tells the story well, too:

picture2.jpg
 
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You said "nobody flies VFR in the clouds".

I don't think so, I'm pretty sure I said, "Nobody flies VFR in the clouds. If they're in the clouds they are not operating in accordance with Visual Flight Rules." If you think that statement is "broken", then please explain how one can operate in the clouds in accordance with Visual Flight Rules.
 
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