Transponder setting in IMC while in Class G

jason

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Jason W (FlyNE)
Without discussing the safety and/or practical aspects of doing such, I have a theoretical question.

Technically, it is legal to fly in IMC while in class G airspace as long as you have an instrument rating. So let's say that I'm departing an airport in class G and hit IMC at 300 ft AGL. I level off at 350 ft. AGL and fly in circles while staying clear of all Class B, C, D and E airspance. Since I don't need to talk to ATC (and as such will not receive a transponder code)...and since I wouldn't squawk 1200 (since I'm not VFR). What should I set my transponder to?
 
My first question is why would you fly at 350 AGL in IMC?

Back to previous question and correct me if I'm wrong but if you're in IMC aren't you required to be on an IFR flight plan?

Another point to is a lot of places such as Kansas city center and Minneapolis might have trouble seeing you that low so although you could put a transponder code in, I'm not sure they'd see you at 300 agl.
 
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While it is technically legal to fly in IMC in Class G without a flight plan or a clearance, you can still get fried for doing it. See Administrator v. Murphy. Also, you would not be legal to "fly in circles" in IMC at 350 AGL (91.177(a)(2)(ii)).

As for what to squawk when operating in IMC in Class G without a flight plan or a clearance, I don't think there is any regulatory or advisory guidance on the subject.
 
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It is pretty hard to depart into IMC in class G without it being considered reckless. That said, I think, you might have a better shot in remote areas where class G goes higher.

Before cell phones, and all our fancy radio coverage, in remote areas of class G where getting a clearance was impossible..it was probably way more common practice.
 
It was not and IS NOT my contention that it would be safe, practical or prudent. Hence my original request not to get flamed for the question on the basis of safety or practicality. It was simply my contention that it was technically legal.

Honestly, I was simply studying for my instrument written and was going over the scenarios in my head when I realized that you wouldn't be able to set your transponder in such a scenario. Knowing that we're all about picking nits here I was sure that somebody had noticed this and had tried to seek out an answer. :)
 
Jason, I think this is a gray area. Like Ron said, there isn't any guidance on this, either. I'd squawk 1200 since there isn't any alternative I'm aware of.

-Felix
 
I always thought that this was a nebulous area of the rules. In particular, there's no specification of when you enter and exit IFR under such circumstances. For instance, if you're flying along, and you pass through a cloud, are you VFR, then IFR, then VFR again? Are you IFR only during the time you're busting VFR minimums? Or is there some notion of you "deciding" that you begin to be IFR?

In any case, there's nothing on the IR written about what you squawk when you're IFR without a clearance, which is good, because I don't think the FAA would know what the right answer is. But I can't see any reason to choose an answer other than "1200".
-harry
 
Without discussing the safety and/or practical aspects of doing such, I have a theoretical question.

Technically, it is legal to fly in IMC while in class G airspace as long as you have an instrument rating. So let's say that I'm departing an airport in class G and hit IMC at 300 ft AGL. I level off at 350 ft. AGL and fly in circles while staying clear of all Class B, C, D and E airspance. Since I don't need to talk to ATC (and as such will not receive a transponder code)...and since I wouldn't squawk 1200 (since I'm not VFR). What should I set my transponder to?

Under the reg Ron cited, it would not be legal to level off at 350 agl. It would have to be at least 1000 agl in flatland, and 2000 agl in designated mountainous areas. There are places where class G airspace goes far above that, and I haven't heard of any case law that deals with flying IFR in such areas. Under 91.215(b) and (c), if you are in such an area, you are probably not in an area that requires the transponder to be turned on.

Probably useless information, I know, but I just thought I would throw that in here. :smile:
 
Before cell phones, and all our fancy radio coverage, in remote areas of class G where getting a clearance was impossible..it was probably way more common practice.
What was common was prepping the airplane, getting everyone/everything strapped in/loaded, going to the pay phone, calling FSS, getting your clearance and void time, and then running to the plane, leaping in, racing through your checklists, and then hover-taxiing to the runway to get airborne before your void time expired. In most cases, trying to get the clearance airborne when the weather was low was an impossibility due to inability to reach ATC that low (below radio/radar coverage).
 
Honestly, I was simply studying for my instrument written
Sweat not -- I don't think you'll find this question on the IR written, and I'm sure you won't on the practical unless posed as a trap into which to fall (i.e., a judgement rather than rules issue, the correct answer to which is "No way in the world I'm gonna go banging up into the goo in G-space below the E-space that low, so who cares what the 'correct' code should be, if there even is one!").
 
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Sweat not -- I don't think you'll find this question on the IR written, and I'm sure you won't on the practical unless posed as a trap into which to fall (i.e., a judgement rather than rules issue, the correct answer to which is "No way in the world I'm gonna go banging up into the goo in G-space below the E-space that low, so who cares what the 'correct' code should be, if there even is one!").

Of course. It was just a gap in the regs and I was curious if anybody else had spotted it and tried to fill in the gap. We tend to do that around here. :yes:

I agree with you that I won't be tested on it. The only thing that I'll need to know is that it's "legal" to fly in class G without a flight plan or a clearance.
 
The only thing that I'll need to know is that it's "legal" to fly in class G without a flight plan or a clearance.
Not necessarily. You won't find this on the written, but it could come up on the practical, so read Murphy carefully.
 
Hmm. In thinking it through I have come to the conclusion that since a transponder is not required for either IFR or VFR flight while in class G airspace the MOST correct answer would be to shut off the transponder. While I believe such an action would subject the pilot to more danger and possibly cross the line into even more reckless behavior, I think that it is the action that most closely follows the "letter of the regs".
 
Hmm. In thinking it through I have come to the conclusion that since a transponder is not required for either IFR or VFR flight while in class G airspace the MOST correct answer would be to shut off the transponder. While I believe such an action would subject the pilot to more danger and possibly cross the line into even more reckless behavior, I think that it is the action that most closely follows the "letter of the regs".
Since there are no regs on the subject, you might want to consider other issues, like whether or not the TCAS/TAS/etc of an airplane flying an approach into the airport from which you are departing will spot you. On that basis, turning your transponder off might be considered careless/reckless.
 
Since there are no regs on the subject, you might want to consider other issues, like whether or not the TCAS/TAS/etc of an airplane flying an approach into the airport from which you are departing will spot you. On that basis, turning your transponder off might be considered careless/reckless.

I'm pretty sure that I did think about that and said as much in the post that you quoted.
 
Not necessarily. You won't find this on the written, but it could come up on the practical, so read Murphy carefully.

Is it your contention that there is no location in the US (Alaska included) in which a flight might be safely completed between two airports while remaining 1) in class G for the duration of the flight 2) on which some IMC may be encountered 3) said IMC is traversed without a flight plan or specific clearance 4) said flight is completed above all applicable MEAs and 5) said flight could be completed without raising the ire of the FAA?
 
Hmm. In thinking it through I have come to the conclusion that since a transponder is not required for either IFR or VFR flight while in class G airspace the MOST correct answer would be to shut off the transponder. While I believe such an action would subject the pilot to more danger and possibly cross the line into even more reckless behavior, I think that it is the action that most closely follows the "letter of the regs".
Jason, I'm not following that argument.

Transponders aren't required in most types of airspace in the US. It's still a good idea to use them. If I were to fly in IMC, I'd always have it on, even if I'm in class G....
 
It would have to be at least 1000 agl in flatland, and 2000 agl in designated mountainous areas.

Unless waivered by the FAA. In the Gulf of Mexico, pipeline patrols routinely file and operate under an IFR flight plan with the ability to go as low as 400 feet AGL (MSL.. same thing in this instance)..

Dont have an answer as to what to squawk. 1200 is VFR. Other codes are assigned as part of a clearance. You don't need a clearance to operate in uncontrolled airspace. Sounds like there is no correct answer regarding the technical legalities.

From a practical perspective, I've already known of too many folks boring holes in the ground, so I would hope nobody I know tries to put this theory into practice.
 
Is it your contention that there is no location in the US (Alaska included) in which a flight might be safely completed between two airports while remaining 1) in class G for the duration of the flight 2) on which some IMC may be encountered 3) said IMC is traversed without a flight plan or specific clearance 4) said flight is completed above all applicable MEAs and 5) said flight could be completed without raising the ire of the FAA?
No, it isn't.
 
Without discussing the safety and/or practical aspects of doing such, I have a theoretical question.

Technically, it is legal to fly in IMC while in class G airspace as long as you have an instrument rating. So let's say that I'm departing an airport in class G and hit IMC at 300 ft AGL. I level off at 350 ft. AGL and fly in circles while staying clear of all Class B, C, D and E airspance. Since I don't need to talk to ATC (and as such will not receive a transponder code)...and since I wouldn't squawk 1200 (since I'm not VFR). What should I set my transponder to?

7700.

It's legal to fly in IMC in Class G airspace as long as you comply with all applicable FARs, level off at 350 AGL and you'll be in violation of FAR 91.177.
 
Under the reg Ron cited, it would not be legal to level off at 350 agl. It would have to be at least 1000 agl in flatland, and 2000 agl in designated mountainous areas.

1000/2000 AGL isn't high enough, the requirement is an altitude of 1000/2000 feet above the highest obstacle within a horizontal distance of 4 nautical miles from the course to be flown.
 
Is it your contention that there is no location in the US (Alaska included) in which a flight might be safely completed between two airports while remaining 1) in class G for the duration of the flight 2) on which some IMC may be encountered 3) said IMC is traversed without a flight plan or specific clearance 4) said flight is completed above all applicable MEAs and 5) said flight could be completed without raising the ire of the FAA?

Here's a specific one for you:

MT08-JDN (Hayes MOA is only active by NOTAM, so let's assume it isn't).

Whole thing is in G-14,500 area, 8,300' MORA.
 
Without referencing any books or official publications: is 1200 a VFR squawk or a VMC squawk? You're still (technically) VFR, just in IMC, so why wouldn't 1200 be correct (or at least acceptable, in what everyone has already pointed out to be a bad situation)?
 
Without referencing any books or official publications: is 1200 a VFR squawk or a VMC squawk? You're still (technically) VFR, just in IMC...

Hmmm, I'm not sure I'd agree with that analysis. You are still operating under IFR, just without a clearance. Fine hair to split I guess
 
Hmmm, I'm not sure I'd agree with that analysis. You are still operating under IFR, just without a clearance. Fine hair to split I guess

You know, until he said that, I would have assumed the same...but look at 61.57(c)

(c) Instrument experience. Except as provided in paragraph (e) of this section, no person may act as pilot in command under IFR or in weather conditions less than the minimums prescribed for VFR, unless within the preceding 6 calendar months, that person has:

Note that it says "under IFR or in weather conditions less than the minimums prescribed for VFR". If you were operating IFR in Class G, then that distinction wouldn't be needed, in that you would be IFR. That means you must be able to operate in less than the minimums for VFR while not being IFR, and that means you gotta be in Class G when doing it, right?
 
You know, until he said that, I would have assumed the same...but look at 61.57(c)



Note that it says "under IFR or in weather conditions less than the minimums prescribed for VFR". If you were operating IFR in Class G, then that distinction wouldn't be needed, in that you would be IFR. That means you must be able to operate in less than the minimums for VFR while not being IFR, and that means you gotta be in Class G when doing it, right?

The way I read it, that could also mean VFR into IMC in controlled airspace.
 
Note that it says "under IFR or in weather conditions less than the minimums prescribed for VFR"
61.3e has the same phrasing for when an instrument rating is required. So let's try to interpret that as meaning that flight in IMC without a clearance is not "under IFR". So what is it, then?

It can't be VFR, because 91.155 specifies VFR weather minimums. If we're in a cloud, we can't be VFR. So if we're not VFR and not IFR, that would have to mean that there's some third choice. What would that be?

Note that 91.173 says:
No person may operate an aircraft in controlled airspace under IFR unless that person has—
(a) Filed an IFR flight plan; and
(b) Received an appropriate ATC clearance.
If you try to take the tack that flying in IMC without a clearance isn't really IFR, then this rule wouldn't necessarily imply. So if we can be "something not IFR" while inside a cloud outside controlled airspace, then we have to acknowledge that there's no requirement to have a clearance for doing that "something not IFR" in controlled airspace, either.

BTW, I don't buy any of this, I think if you're in IMC without a clearance, you're definitely IFR, and that VFR and IFR are the only two choices.
-harry
 
Without referencing any books or official publications: is 1200 a VFR squawk or a VMC squawk?
VFR.
You're still (technically) VFR, just in IMC,
Can't legally be VFR in IMC -- you really are operating IFR albeit without flight plan or clearance.
so why wouldn't 1200 be correct (or at least acceptable, in what everyone has already pointed out to be a bad situation)?
Because you're not operating VFR.
 
Hadn't I heard before that 2000 is the default IFR squawk code for a non-radar environment? I can't remember where :redface: Google just brings up flight sim references on it.
 
The way I read it, that could also mean VFR into IMC in controlled airspace.

Flight under Visual Flight Rules requires that the weather be VMC and that appropriate separation from clouds. Since we're talking about flight in uncontrolled airspace in IMC I think we can assume that such a flight cannot legally be conducted under VFR. Therefore it also seems inescapable that the flight would have to be conducted under Instrument Flight Rules to be legal.

That said, I can find no guidance whatsoever WRT the appropriate code to use when no IFR clearance is involved. This makes me think that the FAA hasn't really considered this as feasible even though there are places in the boonies where a complete IFR trip could be completed entirely within Class G airspace using the appropriate IFR altitudes.
 
Flight under Visual Flight Rules requires that the weather be VMC and that appropriate separation from clouds. Since we're talking about flight in uncontrolled airspace in IMC I think we can assume that such a flight cannot legally be conducted under VFR. Therefore it also seems inescapable that the flight would have to be conducted under Instrument Flight Rules to be legal.

That said, I can find no guidance whatsoever WRT the appropriate code to use when no IFR clearance is involved. This makes me think that the FAA hasn't really considered this as feasible even though there are places in the boonies where a complete IFR trip could be completed entirely within Class G airspace using the appropriate IFR altitudes.

All I meant is that the phrase "or in weather conditions less than the minimums prescribed for VFR" applies to more than just IFR in class G as another poster said.
 
Before cell phones, and all our fancy radio coverage, in remote areas of class G where getting a clearance was impossible..it was probably way more common practice.

Back when men were real men, women were real women, and small fuzzy creatures from alpha centauri were real small fuzzy creatures from alpha centauri. :)
 
Jason, I think this is a gray area. Like Ron said, there isn't any guidance on this, either. I'd squawk 1200 since there isn't any alternative I'm aware of.

FAAO 7110.66C National Beacon Code Allocation Plan assigns code 1200 for "Visual Flight Rule (VFR) aircraft not in radio contact with an ATC facility". It has no code assignment for "Instrument Flight Rule (IFR) aircraft not in radio contact with an ATC facility". There's never been any real need for one, the Class G airspace where aircraft can legally operate IFR tends to be without ATC radar and radio coverage so there was no point in such a code. The advent of TCAS changed that. Code 1400 was formerly assigned to VFR operations above 10,000 MSL and 1200 was for VFR operations below that altitude. Code 1400 remains unassigned, it could be the IFR Class G code.

But I doubt that any code will be assigned for IFR operations in Class G airspace as those operations, while legal, are certainly frowned upon.
 
Why does the code matter?

As long as the transponder is on-
-If ATC can't read the code, it doesn't matter what code was set.

-If ATC can pick up the code, they will at least know someone's out there.

-If a plane has TCAS, they will also see the other plane (assuming active TCAS).

The 1200 code gives a clue that the plane isn't talking.

Another question- I think ATC can clear an IFR plane into class G airspace (subject to terrain), but the pilots use reporting points to let ATC know where they are? If true, I suppose they assume other planes aren't flying IMC, or see & avoid would hold.

Can an IFR flight be cleared into Class G?
 
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Why does the code matter?

As long as the transponder is on-
-If ATC can't read the code, it doesn't matter what code was set.

-If ATC can pick up the code, they will at least know someone's out there.

-If a plane has TCAS, they will also see the other plane (assuming active TCAS).

The 1200 code gives a clue that the plane isn't talking.

Another question- I think ATC can clear an IFR plane into class G airspace (subject to terrain), but the pilots use reporting points to let ATC know where they are? If true, I suppose they assume other planes aren't flying IMC, or see & avoid would hold.

Can an IFR flight be cleared into Class G?

It's my understanding that you can be on an IFR clearance inside class G but that the "clearance" doesn't provide anything besides separation from other IFR traffic. Certainly this is the case when clerared for an approach that penetrates class G in IMC. Seems to me the clearances I've received when launching into class G included the phrase "upon entering controlled airspace" so maybe the clearance doesn't really exist until then.

As to the code, I agree the transponder should be on in mode C and that while there's no guidance, the most appropriate code would be 1200.
 
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Can an IFR flight be cleared into Class G?
No. One can be cleared to leave or enter controlled airspace from/to G-space, but when one is inside G-space, one is not on an IFR clearance, and no separation is provided from nonparticipating aircraft. ATC can, with your approval, give a routing through G-space, but you're on your own for separation while in that G-space, and your clearance to depart controlled airspace should include permission to re-enter controlled airspace on the other side.

That said, ATC will not clear you to enter controlled airspace from G-space (e.g., taking off from an airport where controlled airspace doesn't go to the surface) when they have another aircraft in the airspace into which you'd be going. Hence, the "one in/one out" system which occurs at such airports even when there is uncontrolle airspace between the surface and the base of the overlying E-space.

As for transponder codes, when you are cleared to enter controlled airspace from G-space, they'll give you a code to squawk, and you're expected to squawk it from takeoff. Likewise, when exiting controlled airspace (e.g., flying a SIAP into an airport where the base of controlled airspace is above the surface), you'll be expected to continue squawking your last assigned code until landing or cancelling IFR.
 
Several folks I know on the West coast have taken off from uncontrolled fields and climbed up over the ocean to get up to where there is radar coverage and above weather. Class G can get pretty high up; however, my understanding is this is being done with a clearance or void time. They also descend over the ocean when ceilings are low in class G to get under a layer on the way into an airport. Don't know how low they go, but class G gives them more flexibility with its lower cloud clearances. With mountains on the coast, many of these areas don't have radar coverage, but the airport is close to shore before the mountains. While not on radar, they are talking to approach or departure as soon as they get high enough to get com.

Best,

Dave
 
Several folks I know on the West coast have taken off from uncontrolled fields and climbed up over the ocean to get up to where there is radar coverage and above weather. Class G can get pretty high up; however, my understanding is this is being done with a clearance or void time. They also descend over the ocean when ceilings are low in class G to get under a layer on the way into an airport. Don't know how low they go, but class G gives them more flexibility with its lower cloud clearances. With mountains on the coast, many of these areas don't have radar coverage, but the airport is close to shore before the mountains. While not on radar, they are talking to approach or departure as soon as they get high enough to get com.
Yes, this happens quite frequently.

Many of the coastal airports north of San Francisco have mountains within 1-2 miles to the east. There's no RADAR or comm coverage down there and in addition to that, it's quite often foggy or overcast at 500'. Many people get their clearance, fly out over the water to climb, and then contact ATC. It's a make-it-up DP....

-Felix
 
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