IMC sans ATC

So here is a question for the group. What if the IMC conditions are only within the class G and the above Class E is VMC - can an Instrument rated pilot in an instrument legal airplane depart the class G without a clearance?

Say you experience ground fog at the departure airport and the fog does not extend higher than 500' AGL, but it is crystal clear above.
 
Fearless Tower said:
So here is a question for the group. What if the IMC conditions are only within the class G and the above Class E is VMC - can an Instrument rated pilot in an instrument legal airplane depart the class G without a clearance?

Say you experience ground fog at the departure airport and the fog does not extend higher than 500' AGL, but it is crystal clear above.
Click to expand...

How do you know that the ground fog only extends to 500 AGL might present a problem. To play along, I will assume the airport is in a valley near a lake and in the opposite direction to your departure is a mountain that you happen to live on and as you drive to the airport you can see the top of the fog as you descend down the mountain into the valley.

If the class E airspace is 700 AGL, you will have a problem entering it as you will not be able to maintain the VFR vertical cloud clearance required. If the Class G starts at 1200 AGL, you might have better luck on two fronts. First you might be able to maintain VFR cloud clearance required before entering Class E if the tops were at 200 AG. Second the airport will not be expected to have any instrument approaches, so there little chance of encountering IFR traffic making an approach to the airport resulting in you being able to make an argument that you were not careless and reckless.
 
Last edited:
roncachamp said:
He'll need to clear clouds by 500' below, 1,000' above, and 2,000' horizontally in that scenario, assuming daytime and less than 10,000' MSL.
Click to expand...
Good catch. Thanks. We often forget the rules on cloud clearance for VFR in G-space change above 1200 AGL (although the visibility requirement remains 1 mile up to 10,000 MSL where the cloud clearance also goes up).
 
Fearless Tower said:
So here is a question for the group. What if the IMC conditions are only within the class G and the above Class E is VMC - can an Instrument rated pilot in an instrument legal airplane depart the class G without a clearance?

Say you experience ground fog at the departure airport and the fog does not extend higher than 500' AGL, but it is crystal clear above.
Click to expand...
That is almost exactly the situation in the Murphy case, and he got 90 days on the ground for violating 91.13 by doing that. While John's mention of not knowing for sure just how high the tops were there is well taken, the FAA/NTSB's primary concern was separation from aircraft operating on clearances to enter the controlled airspace from below, or conduct an instrument approach from controlled airspace to land. Further, he also violated 91.155 because when he entered controlled airspace at 700 AGL, he was less than 1000 above the clouds, but the FAA missed that when they charged him on that section only because he operated in the G-space with less than 91.155 G-space VFR mins (a charge he beat by accurately claiming he was operating under IFR, not VFR).
 
Last edited:
Fearless Tower said:
So here is a question for the group. What if the IMC conditions are only within the class G and the above Class E is VMC - can an Instrument rated pilot in an instrument legal airplane depart the class G without a clearance?

Say you experience ground fog at the departure airport and the fog does not extend higher than 500' AGL, but it is crystal clear above.
Click to expand...

Would you have the required cloud clearance when you reached Class E airspace?
 
VMC is not VFR. The premise is you're flying in the soup without a clearance and that wouldn't change just because you're letting down to land. In my scenario you'd let down to 1,500 AGL and make contact with the surface and land.

Just to be clear, I'd never in a million years attempt this. Just wondering how it would work. It appears on the surface to be legal even though there's legal opinion to the contrary. That's why catch all rule like 'Careless and Wreckless' are stupid. It open to interpretation and means nothing. A rule should not be subjective. An action should either be legal or not legal and their cop out that rules can't be made for every circumstance is BS. I've got a five inch thick book full of way more obscure rules than 'not flying into clouds without a clearance'.
 
Captain said:
VMC is not VFR. The premise is you're flying in the soup without a clearance and that wouldn't change just because you're letting down to land. In my scenario you'd let down to 1,500 AGL and make contact with the surface and land.
Click to expand...
1500 AGL isn't always above the 91.177 minimum IFR altitude, especially in the areas where there's a lot of brown on the chart. Those places, it's generally 2000 above the highest obstruction within 4nm of your course, and that may be a lot higher than 2000 AGL.

Just to be clear, I'd never in a million years attempt this. Just wondering how it would work.
Click to expand...
You got that answer from me a few posts up -- cruise at a 91.177/179 legal altitude, descend to be in VMC no less than the 91.177 minimum altitude, and then complete the flight visually from there.

It appears on the surface to be legal even though there's legal opinion to the contrary. That's why catch all rule like 'Careless and Wreckless' are stupid. It open to interpretation and means nothing. A rule should not be subjective. An action should either be legal or not legal and their cop out that rules can't be made for every circumstance is BS. I've got a five inch thick book full of way more obscure rules than 'not flying into clouds without a clearance'.
Click to expand...
If the courts and NTSB thought the idea that it is neither possible nor necessary for the Administrator to anticipate and prohibit every potentially dangerous act was "BS", that rule book would fill a few bookshelves. However, they do, so it remains manageable, and 91.13 remains a subjectively evaluated standard.
 
Captain said:
Okay, I just read 91.177 and 91.179. They don't seem to prohibit the proposed operation. Here's the setup in my mind;

Out west. The class E starts at 14,500 and my city pairs (KABC and KXYZ) are both airports with no IAPs. The MOCA is 7,000'. It's 2SM vis at both airports and cloudy all the way up. Solid IMC. My route is easterly and I'm navigating using GPS. My cruise altitude is 9,000 feet.

The plan is to get in the plane and launch without ever talking to ATC. Ill shoot a contact approach with the 2SM vis at the destination cause I'm that familiar.

Being above the MOCA and using GPS satisfies 91.177 and going east at an odd altitude satisfies 91.179, no?
Click to expand...

Would you turn your transponder on?
 
You should turn your transponder on because you are legally required to turn it on at ALL times in the air, no matter what airspace or altitude, Mode C veil or no... if it is in the aircraft and serviceable. The Mode C veil, above 10000 ft etc are places where you may not fly if unequipped.
 
pericynthion said:
You should turn your transponder on because you are legally required to turn it on at ALL times in the air, no matter what airspace or altitude, Mode C veil or no... if it is in the aircraft and serviceable. The Mode C veil, above 10000 ft etc are places where you may not fly if unequipped.
Click to expand...

What would you squawk in the OPs example?
 
Velocity173 said:
What would you squawk in the OPs example?
Click to expand...

Canada appears to have set aside beacon code 1000 when below 18,000 and code 2000 when above that altitude when IFR in Class G. Australia uses code 2000 for IFR Class G flights for all altitudes. Source:

http://en.wikipedia.org/wiki/Transponder_(aviation)

I presume that means they might still have radar coverage and some sort of traffic advisory service available that doesn't qualify as ATC.
 
Jim Logajan said:
Canada appears to have set aside beacon code 1000 when below 18,000 and code 2000 when above that altitude when IFR in Class G. Australia uses code 2000 for IFR Class G flights for all altitudes. Source:

http://en.wikipedia.org/wiki/Transponder_(aviation)

I presume that means they might still have radar coverage and some sort of traffic advisory service available that doesn't qualify as ATC.
Click to expand...


Seems like there isn't a definitive answer:

http://www.pilotsofamerica.com/forum/archive/index.php/t-29693.html

I can see years down the road an ADS-B in/out system setup where the IMC class G enroute practice wouldn't be all that dangerous. Right now though, I'd never do it.

EDIT: Reading the old thread above, I find it funny how the same topics get brought up months, sometimes years apart. Ron's gotta be getting tired of rehashing this stuff. :D
 
Last edited:
Jim Logajan said:
Canada appears to have set aside beacon code 1000 when below 18,000 and code 2000 when above that altitude when IFR in Class G. Australia uses code 2000 for IFR Class G flights for all altitudes. Source:

http://en.wikipedia.org/wiki/Transponder_(aviation)

I presume that means they might still have radar coverage and some sort of traffic advisory service available that doesn't qualify as ATC.
Click to expand...

Same for several countries in Asia. We will fly code 2000 for IFR in class G.

Also, we have some routes without ATC that are on our own. Once you leave the TMA it's code 2000. The airport we go to has no approach and no approach procedure, just contact the tower and advise them we are inbound and get the wind and temperature. We descend to a minimum altitude and if clear of clouds, proceed to landing, if not climb and go back.
 
pericynthion said:
You should turn your transponder on because you are legally required to turn it on at ALL times in the air, no matter what airspace or altitude, Mode C veil or no... if it is in the aircraft and serviceable. The Mode C veil, above 10000 ft etc are places where you may not fly if unequipped.
Click to expand...

FAR 91.215(c) requires transponder-on operation in all controlled airspace.
 
Captain said:
Only because ABC to XYZ is under a mode C veil. Law an order every time...that's me.
Click to expand...

My apologies. This was a snarky comment to an irrelevant (IMO) question. A lengthy conversation on transponder use is not required for my benefit, thank you.
 
Captain said:
My apologies. This was a snarky comment to an irrelevant (IMO) question. A lengthy conversation on transponder use is not required for my benefit, thank you.
Click to expand...

??? Why would a possible transponder requirement be irrelevant? Apparently it was relevant on the old thread I attached because no one could agree on what to squawk.

The point that I was trying to make is that right now there isn't much benefit in having a transponder on in your scenario. Possibly in the future if everyone was ADS-B in/out this IMC operation in class G wouldn't be all that dangerous if everyone could see one another.
 
Last edited:
There used to be a code to use when IFR in US airspace and no code was assigned (1100, IIRC, might have been 1400), but that was back when a lot of radar facilities didn't yet have SSR. That disappeared from the AIM a long time ago (even before the lost comm triangle pattern, IIRC). I don't think there's any guidance on what to squawk when IFR in uncontrolled airspace without an assigned code (as you'd have when cleared into/out of controlled airspace or operating in the DC SFRA below the floor of controlled airspace).
 
Ron Levy said:
There used to be a code to use when IFR in US airspace and no code was assigned (1100, IIRC, might have been 1400), but that was back when a lot of radar facilities didn't yet have SSR. That disappeared from the AIM a long time ago (even before the lost comm triangle pattern, IIRC). I don't think there's any guidance on what to squawk when IFR in uncontrolled airspace without an assigned code (as you'd have when cleared into/out of controlled airspace or operating in the DC SFRA below the floor of controlled airspace).
Click to expand...

There are nondiscrete codes specified for use by ATC in situations where discrete codes are not available. Code 1100 is for departing IFR aircraft that will remain in low altitude sectors. Long ago, some forty years or so, before Mode C was common, 1400 was for use by VFR aircraft not in contact with ATC operating at or above 10,000 MSL, while 1200 was used below 10,000 MSL.
 
roncachamp said:
There are nondiscrete codes specified for use by ATC in situations where discrete codes are not available. Code 1100 is for departing IFR aircraft that will remain in low altitude sectors. Long ago, some forty years or so, before Mode C was common, 1400 was for use by VFR aircraft not in contact with ATC operating at or above 10,000 MSL, while 1200 was used below 10,000 MSL.
Click to expand...
Ah, yes -- the memory floods back. Then I guess an 1100 code might be a good choice -- clearly 1200 would not because that's only for VFR operations. But you sure wouldn't want to turn it off (which would be a legal option below 10,000 MSL in uncontrolled airspace), since that would take away the ability to be "seen" by any other aircraft with TCAS or other traffic watch system operating in the same airspace (without ATC to help you avoid each other).
 
roncachamp said:
I've received clearances at these airports, I'm sure most IFR pilots have.
Click to expand...

All the time, my home base has no procedures. Taxi and runup, then call the class C tower on the cell phone, advise them of my flight plan. They give a clearance void time and as long as I'm off by then, good.
 
RotorAndWing said:
Same for several countries in Asia. We will fly code 2000 for IFR in class G.

Also, we have some routes without ATC that are on our own. Once you leave the TMA it's code 2000. The airport we go to has no approach and no approach procedure, just contact the tower and advise them we are inbound and get the wind and temperature. We descend to a minimum altitude and if clear of clouds, proceed to landing, if not climb and go back.
Click to expand...

I've done this some in Africa. No approaches, not even an airport diagram for some of the airports we went in to! Can't say I was entirely comfortable with it. Squawk 2000, fly the filed route, get up to around 14,500 and call ATC.
 
You must log in or register to reply here.
Back
Top