VFR Minimum Distance From Clouds G airspace

LongRoadBob

LongRoadBob

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Trying to learn about airspace, and while trying to get this all I got to wondering about the meaning and actual reality of keeping that minimum distance. Please feel free to correct also anything I write below that may be a wrong assumption or idea too.

1) I think other than the idea a VFR pilot should never be flying into a cloud, the distance from idea is because an IFR plane may suddenly be coming out of clouds, is that the main point with minimum distance from clouds?

2) How do you learn to judge distances like that with no reference except clear air between?
Does this come with time? Also 500' below clouds seems hard to judge, but also 1000' above (I'm guessing one or the other?) and 2000' horizontally, I don't know how to judge.

3) "VFR daytime, below 1200' AGL (regardless of MSL) Clear of clouds" means exactly that? No clouds in the sky? Of course one has to take off, being less than 1200' in order to climb above 1200'...

Sorry if these are really dumb questions. I'm trying to get a handle on airspace regulations, how to know you comply, and the classes of airspace. I've been trying to memorize these but realize looking at the spreadsheet (FAA) is the wrong way. Decided to mentally go from G up over in my head to try and see for myself the changes that one has to think about. Even the FAA chart over airspaces doesn't include if a transponder is required, and if it must be mode C type.

To make it worse, though the best information is for US airspace I'm in Norway where as far as I can tell they do not use classes B or E, and A is only used around ONE area (Bodø) from FL195 up.

I think I have to make my own chart and fill it in so I don't learn the wrong rules.

Thanks for any help!
 
1) Yes.
2) Experience. In the mean time, give them extra distance...I have almost 500 hours over 25 years, and the one I still have a problem with is that I still greatly misjudge cloud thickness. I will look at some scattered clouds while flying below, and think, "those clouds look 1000 feet thick..." then I try to fly above, and find that they are 5000 feet thick. It has happened to me several times. I have gotten the hang of calculating 500 feet below or 1000 feet above quite accurately though. 2000 feet away is easier, I think, by comparing the cloud to the ground.
3) Clear of clouds means "stay away from the clouds, do not fly IN THEM."
 
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tawood said:
1) Yes.
2) Experience. In the mean time, give them extra distance...I have almost 500 hours over 25 years, and the one I still have a problem with is that I still greatly misjudge cloud thickness. I will look at the some scattered clouds while flying below, and think, "those clouds look 1000 feet thick..." then I try to fly above, and find that they are 5000 feet thick. It has happened to me several times. I have gotten the hang of calculating 500 feet below or 1000 feet above quite accurately though. 2000 feet away is easier, I think, by comparing the cloud to the ground.
3) Clear of clouds means "stay away from the clouds, do not fly IN THEM."
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Great response, and quick. Thanks so much! Answered pretty much everything.

Do you remember back to learning about classes of airspace? Any tips or thoughts on how to retain all the parameters? Did you learn each class one at a time well, then move on to the next? I'm struggling with this but came to realize I ought to take one at a time starting with G, and moving down the alphabet because MOST airspace where I am is G, next most would be D, after that C (as I said I don't think we have B, but I may want to fly in the US some time).
Mostly just thinking this out, but again it seems there is no all-encompassing spreadsheet that includes all rules that I can see (and I mean other than the rules that are not rigidly standardized but rather marked on sectional charts for each instance) including transponer mode C required, default (is there one?) things that if not marked on the chart...how far out from the airspace do you take contact, etc..

Sorry if it is a lot to ask, like I say just struggling with this a little and you have already helped VERY much with your reply there. Thanks again!
 
LongRoadBob said:
Great response, and quick. Thanks so much! Answered pretty much everything.

Do you remember back to learning about classes of airspace? Any tips or thoughts on how to retain all the parameters? Did you learn each class one at a time well, then move on to the next? I'm struggling with this but came to realize I ought to take one at a time starting with G, and moving down the alphabet because MOST airspace where I am is G, next most would be D, after that C (as I said I don't think we have B, but I may want to fly in the US some time).
Mostly just thinking this out, but again it seems there is no all-encompassing spreadsheet that includes all rules that I can see (and I mean other than the rules that are not rigidly standardized but rather marked on sectional charts for each instance) including transponer mode C required, default (is there one?) things that if not marked on the chart...how far out from the airspace do you take contact, etc..

Sorry if it is a lot to ask, like I say just struggling with this a little and you have already helped VERY much with your reply there. Thanks again!
Click to expand...


Its been awhile...so the only hint I remember was "Cessna 152" for the cloud clearance, which means: (1)000 feet above, (5)00 feet below, (2)000 feet horizontal. And I still sometimes have to stop and think when looking at a sectional and trying to figure out the class G ceiling, or class E floor, depending on which side of the magenta line, or those blue dashed lines you are on, so I guess you are not alone.
As far as where Mode C is needed, the only time you need to worry about that one is when you don't have a transponder, which most aircraft here do.
 
tawood said:
Its been awhile...so the only hint I remember was "Cessna 152" for the cloud clearance, which means: (1)000 feet above, (5)00 feet below, (2)000 feet horizontal. And I still sometimes have to stop and think when looking at a sectional and trying to figure out the class G ceiling, or class E floor, depending on which side of the magenta line, or those blue dashed lines you are on, so I guess you are not alone.
As far as where Mode C is needed, the only time you need to worry about that one is when you don't have a transponder, which most aircraft here do.
Click to expand...

Great, thanks! Yes, I saw that memory help from (I think it was "slacker"') in the IFR Airspace thread...a good one! He also had visibility req. on it.
and 5 F-111 flew high
3 152 flew low.

Again, I appreciate the help!
 
Here's the fun part.

Airspace classes indicate services provided, standardized around the world. For instance, Class B provides separation services to all aircraft.

The rules are NOT the same everywhere. In Australia, you need clearance to enter Class C VFR, for instance.
 
Best way I remembered them was use 3 miles, 1000 above, 500 below and 2000 lateral as your base line - more often than not, this is correct E below 10k, C &D daytime.

Above 10K, planes go faster (ie more than 250 kts, so the distances get bigger (5,1,1,1)

G us close to the ground and uncontrolled, so clear of clouds (day). B is clearance only airspace, so clear of clouds only. Etc.
 
1. Yes, an IFR plane could be flying out of a cloud, or another VFR plane could be operating around the cloud perimeter, like you.

2. Mostly experience, you'll get better at it with time. It's not an exact science, just do the best you can and don't worry about it. There's no one up there measuring the distance between you and a cloud to make sure it's not under the minimum.

3. When you are flying below 1200' AGL, you must remain clear of all clouds. There can be clouds in the sky, but you must remain clear of them, this could be by 100', 10', or 1', your decision. That includes distances above, below and horizontal. When flying above 1200' AGL, then you will have higher cloud clearance, or distance requirements.
In this case clear means distance from clouds, not, clear sky's.
 
LongRoadBob said:
2) How do you learn to judge distances like that with no reference except clear air between?
Does this come with time? Also 500' below clouds seems hard to judge, but also 1000' above (I'm guessing one or the other?) and 2000' horizontally, I don't know how to judge.
...
Click to expand...
In my opinion, in practice, if you're close enough to worry how many feet of clearance you have you're probably too close. The G minimums are basically useless to me as they are way below my minimums anyway.

For the rules, I liked the laminated card: https://www.faasafety.gov/files/gslac/library/documents/2014/Jun/91065/FAA_Airspacecard3.pdf
upload_2017-2-3_10-41-43.png
 
champ driver said:
1. Yes, an IFR plane could be flying out of a cloud, or another VFR plane could be operating around the cloud perimeter, like you.

2. Mostly experience, you'll get better at it with time. It's not an exact science, just do the best you can and don't worry about it. There's no one up there measuring the distance between you and a cloud to make sure it's not under the minimum.

3. When you are flying below 1200' AGL, you must remain clear of all clouds. There can be clouds in the sky, but you must remain clear of them, this could be by 100', 10', or 1', your decision. That includes distances above, below and horizontal. When flying above 1200' AGL, then you will have higher cloud clearance, or distance requirements.
In this case clear means distance from clouds, not, clear sky's.
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Aircraft other than helicopters can operate VFR clear of clouds in Class B airspace, and in Class G airspace when within 1200' of the surface during the day. All aircraft are separated in Class B airspace so that is not a concern. The concern with aircraft legally operating IFR flying out of a cloud exists only beneath Class E 700 areas.
 
Clear of clouds in Class B is there so pilots don't make exaggerated elevation changes to dodge clouds...you can just miss 'em by just a little bit. Everyone's position is closely monitored, so far less chance of a plane popping out of a cloud on a collision course. Easier on the pilots and controllers.
 
You will learn to judge the relative movement between you and the nearby clouds at cruise. Compare to how the ground moves beneath you at 500', 1000' and 2000', during your next trip. You may have to level off and get to cruise speed before going to the next step.
 
Another image similar to the FAA one mentioned above.

https://s-media-cache-ak0.pinimg.com/564x/00/2d/b5/002db523ff1953ed57dec93bc2bf615a.jpg

002db523ff1953ed57dec93bc2bf615a.jpg
 
Joshuajayg said:
Why ONLY under Class E 700 and not other Class G areas?
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under 700 foot class E suggests an airport with an instrument approach that someone has been cleared to fly. While you can be cleared for an approach, under IFR you can't be cleared into class G airspace.
 
Brad Z said:
under 700 foot class E suggests an airport with an instrument approach that someone has been cleared to fly. While you can be cleared for an approach, under IFR you can't be cleared into class G airspace.
Click to expand...

But you can legally fly IFR in Class G(non E700 related) without any clearance.
 
Joshuajayg said:
Why ONLY under Class E 700 and not other Class G areas?
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FARs 91.177 and 91.179 apply, even in Class G airspace. To go lower under IFR requires an instrument approach and an approach requires controlled airspace no higher than 700 AGL.
 
roncachamp said:
FARs 91.177 and 91.179 apply, even in Class G airspace. To go lower under IFR requires an instrument approach and an approach requires controlled airspace no higher than 700 AGL.
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§ 91.177 Minimum altitudes for IFR operations.
(a)Operation of aircraft at minimum altitudes. Except when necessary for takeoff or landing, or unless otherwise ....

Nothing about instrument approach here. It would not make any sense to allow IFR operation in Class G without ATC and then require ATC for landing
 
roncachamp said:
FARs 91.177 and 91.179 apply, even in Class G airspace. To go lower under IFR requires an instrument approach and an approach requires controlled airspace no higher than 700 AGL.
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I was also thinking about departing. I can depart IFR from a field with a high E floor.
 
genna said:
1000 ft above non-mountainous terrain is the minimum
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The minimum is 1,000 feet above the highest obstacle within a horizontal distance of 4 nautical miles from the course to be flown. Note that when the FAA determines MIAs they assume a 200' obstacle has been erected everywhere one can be erected without notification. That's pretty much everywhere away from airports without IAPs and I doubt a pilot would be held to a lesser standard.
 
Thanks for the chart/images. I've saved them off, also the ongoing discussion is informative too.
 
roncachamp said:
The minimum is 1,000 feet above the highest obstacle within a horizontal distance of 4 nautical miles from the course to be flown. Note that when the FAA determines MIAs they assume a 200' obstacle has been erected everywhere one can be erected without notification. That's pretty much everywhere away from airports without IAPs and I doubt a pilot would be held to a lesser standard.
Click to expand...

Yes. No argument. I may be lost at the point you are trying to make, however. My original comment was merely stating that one can be flying in IMC under IFR rules in Class G airspace at any altitude(EDIT: not too low :) ).

Incidentally, while not expressly prohibited, FAA has gone after pilots departing in IMC without clearance and staying under Class E until VMC as a form of reckless flyng(to avoid clearance delay).
 
Another issue with airspace rules such as "clear of clouds", is the question of what is a "cloud".

Sometimes you encounter small white fluffiness in the air, and it's a matter of your opinion or judgment, whether it's substantial enough to call it a cloud. I'm not sure if the FAA has a rule on this, but I figure that if I can see through then it's not a "cloud".

This might seem pedantic, but it's not. I actually encountered such fluff in Class G, on my way to a fly-in, just a week after my private pilot check ride. I had to decide immediately whether to proceed or turn around.
 
NoHeat said:
Another issue with airspace rules such as "clear of clouds", is the question of what is a "cloud".

Sometimes you encounter small white fluffiness in the air, and it's a matter of your opinion or judgment, whether it's substantial enough to call it a cloud. I'm not sure if the FAA has a rule on this, but I figure that if I can see through then it's not a "cloud".

This might seem pedantic, but it's not. I actually encountered such fluff in Class G, on my way to a fly-in, just a week after my private pilot check ride. I had to decide immediately whether to proceed or turn around.
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I've never seen anything from the FAA that allowed getting closer if it's just a little cloud. I do it all the time. I'll brush by a little puff that isn't big enough to even have an airplane inside it and the view around is unobstructed enough that you can see if another airplane is going to punch through it.
 
luvflyin said:
I've never seen anything from the FAA that allowed getting closer if it's just a little cloud. I do it all the time. I'll brush by a little puff that isn't big enough to even have an airplane inside it and the view around is unobstructed enough that you can see if another airplane is going to punch through it.
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My point was not the size, but the transparency of the visible moisture. If I can see through it to the other side, then I'm suggesting it isn't a cloud for the purpose of airspace rules. (Because you would be able to see traffic or obstructions.)

But again, that's just my thought. If the FAA has written a criterion for a "cloud" for airspace rules, I have haven't seen it.
 
NoHeat said:
My point was not the size, but the transparency of the visible moisture. If I can see through it to the other side, then I'm suggesting it isn't a cloud for the purpose of airspace rules. (Because you would be able to see traffic or obstructions.)

But again, that's just my thought. If the FAA has written a criterion for a "cloud" for airspace rules, I have haven't seen it.
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Gotcha.
 
genna said:
§ 91.177 Minimum altitudes for IFR operations.
(a)Operation of aircraft at minimum altitudes. Except when necessary for takeoff or landing, or unless otherwise ....

Nothing about instrument approach here. It would not make any sense to allow IFR operation in Class G without ATC and then require ATC for landing
Click to expand...

How are you going to descend out of that cloud without an instrument approach?
 
Joshuajayg said:
I was also thinking about departing. I can depart IFR from a field with a high E floor.
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Yes, if there's room to operate IFR below that Class E floor. If it's 1200 AGL or lower there's not enough room.
 
genna said:
Yes. No argument. I may be lost at the point you are trying to make, however. My original comment was merely stating that one can be flying in IMC under IFR rules in Class G airspace at any altitude(EDIT: not too low :) ).
Click to expand...

Well, not at just any altitude. Must be a cardinal altitude correct for direction of flight.
 
roncachamp said:
Yes, if there's room to operate IFR below that Class E floor. If it's 1200 AGL or lower there's not enough room.
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I can take off from an airport under class E with a 1200 ft floor while in IMC. I would of course continue to climb into the Class E and would be responsible for my own terrain avoidance. I wouldn't "operate" under that floor if you mean cruise. I would only operate in a climb as an extension of the takeoff which is allowable.
 
Joshuajayg said:
I can take off from an airport under class E with a 1200 ft floor while in IMC. I would of course continue to climb into the Class E and would be responsible for my own terrain avoidance. I wouldn't "operate" under that floor if you mean cruise. I would only operate in a climb as an extension of the takeoff which is allowable.
Click to expand...

What's your situation when you reach Class E airspace?
 
roncachamp said:
What's your situation when you reach Class E airspace?
Click to expand...

Who knows, I would assume I would be IFR in Class E still. I'm would take off from said airfield with an IFR flight plan and a clearance once I reach Class E. I am simply saying the "under a 700 ft Class E floor" didn't sound right.
 
Joshuajayg said:
Who knows, I would assume I would be IFR in Class E still. I'm would take off from said airfield with an IFR flight plan and a clearance once I reach Class E.
Click to expand...

So you picked up an IFR clearance before departure.

I am simply saying the "under a 700 ft Class E floor" didn't sound right.
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Where else might an aircraft legally operating VFR clear of clouds encounter an aircraft legally operating IFR popping out of those clouds?
 
NoHeat said:
My point was not the size, but the transparency of the visible moisture. If I can see through it to the other side, then I'm suggesting it isn't a cloud for the purpose of airspace rules. (Because you would be able to see traffic or obstructions.)

But again, that's just my thought. If the FAA has written a criterion for a "cloud" for airspace rules, I have haven't seen it.
Click to expand...

I guess that's why there are also visibility requirements, 1 mile in class G, 3 miles in class E.
 
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