IFR in Class G airpace

Gary F

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Gary F
There are several areas of Class G airspace to 14,500 in Upper Michigan. Is it legal to go busting through clouds without an ATC clearance? It appears so to me as long as a few basic requirements (IFR pilot, airplane and altitudes) are met. I am certain that many will say that this is not safe but considering the remoteness of these areas and the very low traffic density it is probably safer than flying VFR under Class B airspace or over a VOR in an area with a high training volume.

http://www.faa.gov/air_traffic/publications/atpubs/aim/aim0303.html
 
There are several areas of Class G airspace to 14,500 in Upper Michigan. Is it legal to go busting through clouds without an ATC clearance? It appears so to me as long as a few basic requirements (IFR pilot, airplane and altitudes) are met. I am certain that many will say that this is not safe but considering the remoteness of these areas and the very low traffic density it is probably safer than flying VFR under Class B airspace or over a VOR in an area with a high training volume.

http://www.faa.gov/air_traffic/publications/atpubs/aim/aim0303.html

Completely legal. The only downside is you may encounter someone else doing the same thing at the same time at the same altitude and position. But that's unlikely.
 
It appears that a couple of these areas are in Big Bear MOA. How can that be? It is a little scary to fly in these under VFR when hot. Is there a prohibition for flying under IFR when active?

What is used as a transponder code? 1200? that doesn't make any sense either.

Can you ask for traffic advisories?
 
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Completely legal. The only downside is you may encounter someone else doing the same thing at the same time at the same altitude and position. But that's unlikely.

What am I missing here. I understood that class G required "clear of clouds"...
 
It appears that a couple of these areas are in Big Bear MOA. How can that be? It is a little scary to fly in these under VFR when hot. Is there a prohibition for flying under IFR when active?

Flying in a MOA is not prohibited at all, VFR or IFR. ATC will reroute IFR aircraft around them*, but only the IFR aircraft they are working. You can punch through clouds in the Class G airspace in this area in compliance with Instrument Flight Rules. Note that when IMC prevails in the area of a MOA the military activity that had been planned tends to be cancelled.

*IFR traffic can be cleared through a MOA if separation is provided by ATC. I know of no examples of this, however.

What is used as a transponder code? 1200? that doesn't make any sense either.

Can you ask for traffic advisories?

1200 is for VFR aircraft not being worked by ATC, there is no code for IFR aircraft not being worked by ATC.

Where radar coverage and direct pilot/controller communications exist ATC has the ability to provide radar services. And because ATC can provide service these areas tend to be controlled airspace. Traffic advisories are unlikely to be available where the floor of controlled airspace is 14,500 MSL.
 
What am I missing here. I understood that class G required "clear of clouds"...
Class G
1,200 feet or less above the surface (regardless of MSL altitude).



Day, except as provided in section 91.155(b)
1 statute mile
Clear of clouds
Night, except as provided in section 91.155(b)
3 statute miles
500 feet below
1,000 feet above
2,000 feet horizontal

More than 1,200 feet above the surface but less than 10,000 feet MSL.


Day
1 statute mile
500 feet below
1,000 feet above
2,000 feet horizontal

Night
3 statute miles
500 feet below
1,000 feet above
2,000 feet horizontal

More than 1,200 feet above the surface and at or above 10,000 feet MSL.
5 statute miles
1,000 feet below
1,000 feet above
1 statute mile horizontal

http://www.faa.gov/air_traffic/publications/atpubs/aim/aim0301.html#tbB190ROBE


Applies to VFR.
Exactly. I am trying to make sense out of IFR in Class G which is a quirky thing. One of my friends went on a fishing trip to a remote area in Canada by seaplane and told me they went into the clouds on occasion. Based on the remoteness of the lake I doubt that they were on an IFR flight plan.
 
There are several areas of Class G airspace to 14,500 in Upper Michigan. Is it legal to go busting through clouds without an ATC clearance?
Yes, so long as you and your airplane are certified and current for IFR flight.

As the regs say,

==============================
§ 91.173 ATC clearance and flight plan required.
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.
==============================

In uncontrolled airspace, no ATC clearance is required (subject to the "reckless" problem - someone is bound to point to the case of the pilot taking off IFR from Class G on the west coast who got nailed because of the potential impact on other traffic).

Edit: Knew I had a link to the case somewhere: http://www.ntsb.gov/alj/o_n_o/docs/AVIATION/3935.PDF)

I did what has been described just last summer - a few small clouds in a relatively remote area with little likelihood of conflicting traffic.
 
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What am I missing here. I understood that class G required "clear of clouds"...

Day VFR operations in Class G airspace within 1200 feet of the surface requires a minimum of one mile visibility and clear of clouds, but we're discussing IFR operations in Class G airspace.
 
In uncontrolled airspace, no ATC clearance is required (subject to the "reckless" problem - someone is bound to point to the case of the pilot taking off IFR from Class G on the west coast who got nailed because of the potential impact on other traffic).

Edit: Knew I had a link to the case somewhere: http://www.ntsb.gov/alj/o_n_o/docs/AVIATION/3935.PDF)

Based on the particular set of actions by that pilot that day and the BS story he created to talk his way out of a violation, I would not derive a general prohibition against instrument flight in 'high G' from that NTSB decision.
 
Based on the particular set of actions by that pilot that day and the BS story he created to talk his way out of a violation, I would not derive a general prohibition against instrument flight in 'high G' from that NTSB decision.

True, but maintaining IFR in Class G outside of the high-G is tough. You are required to maintain 1,000' above the highest obstacle within 4 nm of your course, and remain below 1,200' AGL (it's just not possible in the 700' AGL Class E areas, so I'll ignore them)...that's a really tight needle to thread...one 199' tower 3 1/2 miles off to your left and you're busted.
 
True, but maintaining IFR in Class G outside of the high-G is tough. You are required to maintain 1,000' above the highest obstacle within 4 nm of your course, and remain below 1,200' AGL (it's just not possible in the 700' AGL Class E areas, so I'll ignore them)...that's a really tight needle to thread...one 199' tower 3 1/2 miles off to your left and you're busted.

It's also impossible in the 1200' AGL Class E areas as your cruising altitude must be a cardinal altitude correct for your direction of flight.
 
It's also impossible in the 1200' AGL Class E areas as your cruising altitude must be a cardinal altitude correct for your direction of flight.

Damn, forgot that one...the <3,000' AGL exception is for VFR, not IFR, cruising altitudes.
 
*IFR traffic can be cleared through a MOA if separation is provided by ATC. I know of no examples of this, however.
I have been cleared IFR through an active MOA. They were working 10,000 and up, and I was cleared through at 6000. Controller coordinated. Rare, but it happens.
 
True, but maintaining IFR in Class G outside of the high-G is tough. You are required to maintain 1,000' above the highest obstacle within 4 nm of your course, and remain below 1,200' AGL (it's just not possible in the 700' AGL Class E areas, so I'll ignore them)...that's a really tight needle to thread...one 199' tower 3 1/2 miles off to your left and you're busted.
In addition, the FAA considers it careless/reckless to operate IFR in the G-space between the surface of an airport with IFR procedures and the overlying E-space. See Administrator v Murphy for details.
http://www.ntsb.gov/legal/o_n_o/docs/Aviation/3935.pdf
 
Damn, forgot that one...the <3,000' AGL exception is for VFR, not IFR, cruising altitudes.

If the pilot was above the cloud deck with at least 1 mile visibility and below the Class E floor, he would be VFR. I don't know if it would have changed the ruling if the pilot was able to know prior to takeoff that the tops were below the class E floor if that would have made a difference in the 91.13 ruling, but the cited case was quoted stating : "a pilot departing from an uncontrolled field in instrument conditions but without a clearance has no assurance that VFR conditions will prevail when he reaches controlled airspace." If the pilot had requested and received a top report from a departing IFR aircraft, then this objection might not be true. This kind of ground fog occurs often in the central valley of California where the tops are only a few hundred feet above the airport.

The second point quoted in the cited reference states: "also create the hazard of a collision with other aircraft. The see and avoid concept would be nullified and there would be no other means of assuring separation from other aircraft." In theory at least, this could be mitigated if the aircraft had an active TCAD or TCAS system on board.

What remains ominous is the note 7 which reads "Moreover, our decision in Administrator v. Vance, 5 NTSB 1037, provided constructive, if not actual, notice that a takeoff into uncontrolled airspace under IFR without an ATC clearance constitutes an independent violation of section 91.13(a)." With this note, I would not be willing to depart into class G under IMC conditions without a clearance.
 
If the pilot was above the cloud deck with at least 1 mile visibility and below the Class E floor, he would be VFR. I don't know if it would have changed the ruling if the pilot was able to know prior to takeoff that the tops were below the class E floor if that would have made a difference in the 91.13 ruling, but the cited case was quoted stating : "a pilot departing from an uncontrolled field in instrument conditions but without a clearance has no assurance that VFR conditions will prevail when he reaches controlled airspace." If the pilot had requested and received a top report from a departing IFR aircraft, then this objection might not be true. This kind of ground fog occurs often in the central valley of California where the tops are only a few hundred feet above the airport.

The second point quoted in the cited reference states: "also create the hazard of a collision with other aircraft. The see and avoid concept would be nullified and there would be no other means of assuring separation from other aircraft." In theory at least, this could be mitigated if the aircraft had an active TCAD or TCAS system on board.

What remains ominous is the note 7 which reads "Moreover, our decision in Administrator v. Vance, 5 NTSB 1037, provided constructive, if not actual, notice that a takeoff into uncontrolled airspace under IFR without an ATC clearance constitutes an independent violation of section 91.13(a)." With this note, I would not be willing to depart into class G under IMC conditions without a clearance.


you cannot depart into Class G under IMC conditions with a clearance. ATC will not clear you for anything in Class G. It is uncontrolled airspace.
 
I have been cleared IFR through an active MOA. They were working 10,000 and up, and I was cleared through at 6000. Controller coordinated. Rare, but it happens.
Yes but in Class G IFR no controller is involved so I suspect that there must be a prohibition for operating IFR in high Class G in a MOA if it is active.
 
you cannot depart into Class G under IMC conditions with a clearance. ATC will not clear you for anything in Class G. It is uncontrolled airspace.

But, you can receive a clearance into the overlying Class E airspace.
 
you cannot depart into Class G under IMC conditions with a clearance. ATC will not clear you for anything in Class G. It is uncontrolled airspace.

Whenever you depart an airport without a surface area you are departing into Class G airspace. Aircraft are routinely issued IFR clearances at such airports in IMC.
 
you cannot depart into Class G under IMC conditions with a clearance. ATC will not clear you for anything in Class G. It is uncontrolled airspace.
We're getting into semantics. People depart into Class G airspace with a clearance to enter the overlying controlled airspace all the time, and ATC is happy to issue that clearance. If that were not so, we could not make IFR departures from airports without controlled airspace to the surface. It is departing into the G-space overlying an airport in IMC without that clearance to enter the overlying controlled airspace that is considered careless/reckless in violation of 91.13(a) for the reasons stated in the Murphy case linked above.

True, you do not get a clearance to cover than 700 feet vertical distance of G-space from ATC, but in order to prevent collisions, the FAA and NTSB have made it clear they don't want anyone operating IFR in IMC in that G-space without a clearance up into or down from the overlying controlled airspace. That way, while ATC isn't technically providing separation from other IFR traffic, no other traffic can operate legally in that space in less than VMC while you're departing or shooting the approach with your ATC clearance into or down from the overlying controlled airspace.
 
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True, but maintaining IFR in Class G outside of the high-G is tough. You are required to maintain 1,000' above the highest obstacle within 4 nm of your course, and remain below 1,200' AGL (it's just not possible in the 700' AGL Class E areas, so I'll ignore them)...that's a really tight needle to thread...one 199' tower 3 1/2 miles off to your left and you're busted.

Garys question was specifically about the areas of 'high G' on the UP or in other remote areas of the country.

Flying in IMC at 1001-1199ft AGL would not seem to be a very safe operation to me, even if it was legal.

The way I understand the the instrument flight in 'high G' issue is that one could fly VFR above a broken or overcast layer in 'high-G' country and penetrate that layer, e.g. to land at ones farm-strip below.

In addition to the 'big sky theory', the second governing principle of operations in high-G is 'Russia is great, god is high above, and the Tsar is far away'.
 
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That said, it might not be the smartest thing to do, regardless of it being "legal" to do so!

I'm not an advocate of the practice, but if IMC prevails in the MOA the training activity planned by the military will likely be cancelled.
 
I'm not an advocate of the practice, but if IMC prevails in the MOA the training activity planned by the military will likely be cancelled.
...probably, but not necessarily. Some military aircraft do "all-weather" operations, and may still be running intercepts or the like even in IMC.
 
I have been cleared IFR through an active MOA. They were working 10,000 and up, and I was cleared through at 6000. Controller coordinated. Rare, but it happens.

Around these parts they just include the altitudes they'll actually be using in the NOTAM activating the MOA.
 
Garys question was specifically about the areas of 'high G' on the UP or in other remote areas of the country.

Flying in IMC at 1001-1199ft AGL would not seem to be a very safe operation to me, even if it was legal.

The way I understand the the instrument flight in 'high G' issue is that one could fly VFR above a broken or overcast layer in 'high-G' country and penetrate that layer, e.g. to land at ones farm-strip below.

In addition to the 'big sky theory', the second governing principle of operations in high-G is 'Russia is great, god is high above, and the Tsar is far away'.
There is very little traffic up here even around most of the populated areas and almost none in the high Class G areas.
 
...probably, but not necessarily. Some military aircraft do "all-weather" operations, and may still be running intercepts or the like even in IMC.

"Likely" and "probably" are synonyms.
 
Day VFR operations in Class G airspace within 1200 feet of the surface requires a minimum of one mile visibility and clear of clouds, but we're discussing IFR operations in Class G airspace.

It was not clear to me the OP was talking about IFR. I had thought IFR requires a clearance... If one does not have a clearance, how is he operating IFR?
 
It was not clear to me the OP was talking about IFR. I had thought IFR requires a clearance... If one does not have a clearance, how is he operating IFR?
That is what is so interesting about IFR in high Class G, it is apparently legal to do this without a clearance or getting ATC involved. You are on your own in terms of aircraft separation from any similarly minded pilots but probably not much of an issue due to the extremely low traffic density.
 
Re: IFR in Class G airspace

It was not clear to me the OP was talking about IFR.

Well, the thread title is "IFR in Class G airspace", so...

I had thought IFR requires a clearance...

§ 91.173 ATC clearance and flight plan required.

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 one does not have a clearance, how is he operating IFR?

By operating in IMC under applicable regulations. If IFR operation was limited to controlled airspace you wouldn't see things like what is highlighted here:

§ 91.179 IFR cruising altitude or flight level.

Unless otherwise authorized by ATC, the following rules apply—

(a) In controlled airspace. Each person operating an aircraft under IFR in level cruising flight in controlled airspace shall maintain the altitude or flight level assigned that aircraft by ATC. However, if the ATC clearance assigns “VFR conditions on-top,” that person shall maintain an altitude or flight level as prescribed by §91.159.

(b) In uncontrolled airspace. Except while in a holding pattern of 2 minutes or less or while turning, each person operating an aircraft under IFR in level cruising flight in uncontrolled airspace shall maintain an appropriate altitude as follows:

(1) When operating below 18,000 feet MSL and—

(i) On a magnetic course of zero degrees through 179 degrees, any odd thousand foot MSL altitude (such as 3,000, 5,000, or 7,000); or

(ii) On a magnetic course of 180 degrees through 359 degrees, any even thousand foot MSL altitude (such as 2,000, 4,000, or 6,000).

(2) When operating at or above 18,000 feet MSL but below flight level 290, and—

(i) On a magnetic course of zero degrees through 179 degrees, any odd flight level (such as 190, 210, or 230); or

(ii) On a magnetic course of 180 degrees through 359 degrees, any even flight level (such as 180, 200, or 220).

(3) When operating at flight level 290 and above in non-RVSM airspace, and—

(i) On a magnetic course of zero degrees through 179 degrees, any flight level, at 4,000-foot intervals, beginning at and including flight level 290 (such as flight level 290, 330, or 370); or

(ii) On a magnetic course of 180 degrees through 359 degrees, any flight level, at 4,000-foot intervals, beginning at and including flight level 310 (such as flight level 310, 350, or 390).

(4) When operating at flight level 290 and above in airspace designated as Reduced Vertical Separation Minimum (RVSM) airspace and—

(i) On a magnetic course of zero degrees through 179 degrees, any odd flight level, at 2,000-foot intervals beginning at and including flight level 290 (such as flight level 290, 310, 330, 350, 370, 390, 410); or

(ii) On a magnetic course of 180 degrees through 359 degrees, any even flight level, at 2000-foot intervals beginning at and including flight level 300 (such as 300, 320, 340, 360, 380, 400).

[Doc. No. 18334, 54 FR 34294, Aug. 18, 1989, as amended by Amdt. 91–276, 68 FR 61321, Oct. 27, 2003; 68 FR 70133, Dec. 17, 2003; Amdt. 91–296, 72 FR 31679, June 7, 2007]
 
...which is different than clearing you through at active altitudes.
Active by NOTAM? Yes. Active by actual usage? No. I've heard them coordinate transit at NOTAM-active altitudes on the fly when they can raise the users (i.e., not off on tactical freq).
 
That is what is so interesting about IFR in high Class G, it is apparently legal to do this without a clearance or getting ATC involved. You are on your own in terms of aircraft separation from any similarly minded pilots but probably not much of an issue due to the extremely low traffic density.
Given the small amount of area where this is possible outside the Rocky Mountain regions (where very few folks want to operate IFR in the big brown areas on the L-charts anyway), this is more an academic discussion than one of practical value.
 
Given the small amount of area where this is possible outside the Rocky Mountain regions (where very few folks want to operate IFR in the big brown areas on the L-charts anyway), this is more an academic discussion than one of practical value.

I would think that with the prevalence of /G now, it might be becoming more dangerous. Before, a larger amount of traffic was confined to the airways, which of course are controlled airspace. With more /G aircraft going D->, and cutting through those Class G airspace, there might be more potential for conflicts.

But, seriously, in those areas, the sky truly is really, really, big!
 
Given the small amount of area where this is possible outside the Rocky Mountain regions (where very few folks want to operate IFR in the big brown areas on the L-charts anyway), this is more an academic discussion than one of practical value.
Not really. I would like to do a little cloud surfing (less than minimum VFR cloud clearance) without the hassle of filing IFR or requesting a defined area of airspace from ATC to do this. These high Class G areas are in my backyard. I want to find out what is legal first then I will decide if the risk is acceptable. I fly through one of these areas when I fly direct from KSAW to Mackinac Island.
 
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I would think that with the prevalence of /G now, it might be becoming more dangerous. Before, a larger amount of traffic was confined to the airways, which of course are controlled airspace. With more /G aircraft going D->, and cutting through those Class G airspace, there might be more potential for conflicts.
The problems with using those areas as a short-cut are first, 2000 above may be not be below the top of the brown, and second, you need a clearance back into controlled airspace on the other side, which may be very hard to coordinate.
 
The problems with using those areas as a short-cut are first, 2000 above may be not be below the top of the brown, and second, you need a clearance back into controlled airspace on the other side, which may be very hard to coordinate.
I would like to do this in VFR conditions but not be restricted to VFR cloud clearance requirements. ATC radio or radar coverage in many parts of the U.P. is nonexistent or spotty. The Class G areas I am referring to are surface to 14,500.
 
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