Uncontrolled IFR

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Dave S.

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thetexan
Can an IFR pilot fly an IFR flight in uncontrolled airspace without a IFR flight plan or a clearance from ATC? 91.173 requires a flight plan and clearance in controlled airspace but can you infer the reverse; that no flight plan is required and no clearance is required, therefore, in uncontrolled airspace?

If IFR flight is is not allowed completely in uncontrolled airspace then there is no need for a rule concerning flight plans or clearances in uncontrolled airspace. If, however, IFR flight is allowed completely in uncontrolled airspace then the rule concerning controlled airspace flight plans and clearance imply the reverse for uncontrolled airspace.

in other words, does the absence of any rule concerning uncontrolled airspace flight plans and clearances in 91.173 necessarily imply that IFR flight in uncontrolled airspace is allowed with flight plans or clearances?

Many sources say that you can. But doesn’t that render any VFR minimums in uncontrolled airspace useless? I can be flying along VFR clear of the clouds in uncontrolled airspace when suddenly, oops!?, I just went into the clouds instead of remaining clear-a violation of 91.155. Oh well, no problem I’ll just be IFR during that time. I’m not so sure about this.

just read the FAA 2016 Lamb interpretation Which confirms that you can but this seems incompatible with several rules.

tex
 
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Dave S. said:
Can an IFR pilot fly an IFR flight in uncontrolled airspace without a IFR flight plan or a clearance from ATC? 91.173 requires a flight plan and clearance in controlled airspace but can you infer the reverse; that no flight plan is required and no clearance is required, therefore, in uncontrolled airspace?

If IFR flight is is not allowed completely in uncontrolled airspace then there is no need for a rule concerning flight plans or clearances in uncontrolled airspace. If, however, IFR flight is allowed completely in uncontrolled airspace then the rule concerning controlled airspace flight plans and clearance imply the reverse for uncontrolled airspace.

in other words, does the absence of any rule concerning uncontrolled airspace flight plans and clearances in 91.173 necessarily imply that IFR flight in uncontrolled airspace is allowed with flight plans or clearances?

Many sources say that you can. But doesn’t that render any VFR minimums in uncontrolled airspace useless? I can be flying along VFR clear of the clouds in uncontrolled airspace when suddenly, oops!?, I just went into the clouds instead of remaining clear-a violation of 91.155. Oh well, no problem I’ll just be IFR during that time. I’m not so sure about this.

just read the FAA 2016 Lamb interpretation Which confirms that you can but this seems incompatible with several rules.

tex
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In 2021 in the US, the lack of Class G includes the inability to comply with several rules, making a real, complete uncontrolled IFR flight impractical. I did an article for IFR Magazine on it - subscription not required for this one.
 
I don't know about the west, but almost the entire eastern half of the country is covered by class E. To remain below 1200ft, fly in the clouds and not go splat would be a mean party trick.
 
Looks like the only G above 1200 left in the 48 contig-US is an area that's an arc 62nm east of and centered on PRS starting at the US-Mexico border, counterclockwise to 30º North, east to the intersection of an arc of 90nm from DLF counterclockwise to the US- Mexico border.

There was up until recently a couple of very small slivers left somewhere in one or two of the "4 corners" states, but I don't see them any more. So I guess you could fly IFR in that last remaining section, but there's only a few private strips in that area.

Edit: Looks like there's a few chunks in Montana as well.
 
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EdFred said:
Looks like the only G above 1200 left in the 48 contig-US is an area that's an arc 62nm east of and centered on PRS starting at the US-Mexico border, counterclockwise to 30º North, east to the intersection of an arc of 90nm from DLF counterclockwise to the US- Mexico border.

There was up until recently a couple of very small slivers left somewhere in one or two of the "4 corners" states, but I don't see them any more. So I guess you could fly IFR in that last remaining section, but there's only a few private strips in that area.

Edit: Looks like there's a few chunks in Montana as well.
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I think the way it works is, when the FAA regulates airspace, it uses specific guidelines to define what is being regulated. Class G is whatever is left behind, and sometimes it ends up being slivers between Class E defined areas.
 
midlifeflyer said:
I think the way it works is, when the FAA regulates airspace, it uses specific guidelines to define what is being regulated. Class G is whatever is left behind, and sometimes it ends up being slivers between Class E defined areas.
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And then when it's no longer needed they don't ever seem to give it back.

standish.jpg
 
Bill said:
I don't know about the west, but almost the entire eastern half of the country is covered by class E. To remain below 1200ft, fly in the clouds and not go splat would be a mean party trick.
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There is essentially no Class G above 1,200 feet in 49 states. There are little "artifact chunks" in the Western U.S. that were missed in the multiple layers of rulemaking, but those small chucks are useless.
 
Let’s put it this way, I have flown IFR in Class G airspace in IMC conditions 25 years ago.

Example one was after departing Minot on a SE bound flight. Upon entering Glass G airspace, ATC advised radar service terminated, report an intersection.

Example 2 was after filing an IFR flight plan leaving a public grass airport in ND. The flight was IMC until I contacted Minneapolis Center for clearance prior to entering Class E.

That was during a time when there literally may not have been any IFR flights over ND at various time of the day. The oil boom killed those Class G areas.
 
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There's a lot of uncontrolled airspace in the world, just not in the lower-49 US states. I've operated IFR out of an airport where controlled airspace started at FL245 (FJDG). Because of the state of airspace in most of the US, some IFR rules might not seem to make sense unless you consider the airspace in Alaska and international airspace.
 
It seems like one of those things where changing the rule would be more difficult than just changing the airspace.

Quite a bit of that airspace sits so empty out west here in any sort of bad weather, it honestly wouldn’t need to be called controlled. It barely sees traffic in good weather.

Kinda no point either way (calling it controlled or bothering to fly in it in the clag).

Leftovers from the days when you had to report to them where you were in your flight or they had no way of knowing anyway.
 
denverpilot said:
It seems like one of those things where changing the rule would be more difficult than just changing the airspace.

Quite a bit of that airspace sits so empty out west here in any sort of bad weather, it honestly wouldn’t need to be called controlled. It barely sees traffic in good weather.

Kinda no point either way (calling it controlled or bothering to fly in it in the clag).

Leftovers from the days when you had to report to them where you were in your flight or they had no way of knowing anyway.
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@David Megginson can probably tell us more, but it's still done in parts of Canada and it doesn't involve reporting to ATC. There's a system of self-reporting and, I suppose they have a hemispheric rule for uncontrolled IFR, just like we do.
 
midlifeflyer said:
@David Megginson can probably tell us more, but it's still done in parts of Canada and it doesn't involve reporting to ATC. There's a system of self-reporting and, I suppose they have a hemispheric rule for uncontrolled IFR, just like we do.
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I've done uncontrolled IFR only a couple of times — pilots up north would have a lot more to say about it — but basically, it works like this:
  1. File a flight plan or flight itinerary (the latter is just letting a reaponsible person, like a friend or dispatcher, know where you're going, and having them agree to call SAR if you don't report in by a certain time).
  2. Squawk 1000 for uncontrolled IFR (similar to 1200 for uncontrolled VFR — I guess that's mainly for the benefit of TCAS, since ATC won't see you on radar).
  3. Follow the hemispheric IFR altitude rules, as @midlifeflyer mentioned.
  4. Make position reports and coordinate with other traffic on 126.7, which is the common (uncontrolled) enroute frequency for VFR and IFR everywhere in Canada.
One more note — a TSB accident report a while back recommended flying an offset to the right of the course centreline. Before GPS, radio navaids—mostly NDBs up north—were imprecise enough that two planes were unlikely to come nose to nose, but with GPS, there's an increased risk of a head-on collision during climbs and descents, when the hemispheric rules don't offer any protection.

I'll also add that if you go to the far north (which I haven't), everyone sets their altimeters to 29.92 inHg, just like in the flight levels. That prevents any confusion about altitude when weather stations might be hundreds of miles apart.

Cheers, David
 
midlifeflyer said:
@David Megginson can probably tell us more, but it's still done in parts of Canada and it doesn't involve reporting to ATC. There's a system of self-reporting and, I suppose they have a hemispheric rule for uncontrolled IFR, just like we do.
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Ha. I was more saying that the heavy bureaucracy of a law change to remove the concept altogether is harder than just making arbitrary airspace changes until there’s nowhere left to do it. Way easier. If the goal is to eradicate it.

(The goal can’t possibly be traffic related. They’re still handing out cruise clearances to the cargo kids in Nebraska at night. “Nobody between you and your godforsaken destination kid, cleared to cruise...” haha. ZDV ain’t busy at 2AM even in cowtown. Haha.)

But yeah, fun trivia about the Great White North and having to do it where civilization ends, too. Rules about flying where nobody is and nobody can see you anyway... ha.
 
denverpilot said:
Ha. I was more saying that the heavy bureaucracy of a law change to remove the concept altogether is harder than just making arbitrary airspace changes until there’s nowhere left to do it. Way easier. If the goal is to eradicate it.
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I think you are right. There's no specific regulation saying uncontrolled IFR is legal anyway. Rather, like many other areas it's a mix of lack of regulation and phrasing.

For example, the IFR hemispheric rule only applies in uncontrolled airspace. The flight plan and clearance requirements only apply in controlled airspace. The minimum altitude rules apply to IFR generally. You'd basically have to tweak all the regs which mention "controlled" and delete the ones which only apply to uncontrolled. That's a pretty large regulatory undertaking with very little practical importance, and I think a big risk of messing it up.
 
I've never done a full start-to-end uncontrolled IFR flight — just starting uncontrolled, then picking up a clearance along the way. I'm trying to think how far north I'd have to go from Ottawa where I could fly IFR from one class G airport with an IAP to another without crossing a class E airway. I'll look at the charts after work, but I don't think it would be that far.
 
Note that while you it doesn't require a flight plan or a clearance (in fact, a clearance is unavailable there), that doesn't obviate you from following all the other IFR rules in part 91 including fuel and alternate requirements, currency, inspections, etc...

Note that the FAA has had an upheld enforcement action that says if you takeoff into uncontrolled airspace in IMC without a clearance for the overlying controlled airspace that you're likely to continue on into it's "careless and reckless" even if it's not strictly against the rules requiring such clearance.
 
Clip4 said:
Let’s put it this way, I have flown IFR in Class G airspace in IMC conditions 25 years ago.

Example one was after departing Minot on a SE bound flight. Upon entering Glass G airspace, ATC advised radar service terminated, report an intersection.

Example 2 was after filing an IFR flight plan leaving a public grass airport in ND. The flight was IMC until I contacted Minneapolis Center for clearance prior to entering Class E.

That was during a time when there literally may not have been any IFR flights over ND at various time of the day. The oil boom killed those Class G areas.
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You can still get ‘Radar Service Terminated’ in Controlled Airspace. Not as often nowadays with much better Radar Coverage than many moons ago. Back in the day when there were still big chunks of G below 14,500 you could get ‘leaving controlled airspace,’ maybe with or maybe not with a ‘Radar service terminated.’ Use of RNAV which became very widespread with GPS led to many requests for ‘direct’ somewhere. The sky then was filled with pieces of Controlled Airspace that were 8 miles wide, the width of a Victor Airway. You would see lots of ‘triangular’ shaped pieces of G in between that were a result of this. The FAA began a program of eliminating G above 1200 AGL in what basically amounted to ‘navigable’ airspace. Maybe the oil boom would have contributed to moving that area up the priority list.
 
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In fact, ATC wouldn't have wanted reporting points if you were in uncontrolled airspace. Lack of radar service doesn't imply you aren't in controlled airspace or under control.

I've been flying through coastal NC and had them say "hey the radar is out at Seymour Johnson, we're going to have to put you back on an airway." It was then I realized what a boon the GNS480 was. You expand your flight plan and it gives you the ETAs for tall the intersections on the airway you're coming up on. Makes it easy to make the report. ATC was busy asking people to make specific reports, though what they were asking for were the mandatory reports if pilots these days knew how to operate in non-radar environments.
 
flyingron said:
Note that while you it doesn't require a flight plan or a clearance (in fact, a clearance is unavailable there), that doesn't obviate you from following all the other IFR rules in part 91 including fuel and alternate requirements, currency, inspections, etc...
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The only IFR rules it obviates are those which use some form of the phrase, "in controlled airspace under IFR"
 
image_2021-03-04_125220.png Here is a bit of airspace where an such a flight may have been performed to get above a marine layer in the past few years. In fact the pilot may have done so using needle ball and airspeed to maintain straight and level. I've been told that the technique still works.
 
Arnold said:
View attachment 94413 Here is a bit of airspace where an such a flight may have been performed to get above a marine layer in the past few years. In fact the pilot may have done so using needle ball and airspeed to maintain straight and level. I've been told that the technique still works.
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The technique works well, but it should be pointed out that the pilot also had the other gyroscopic instruments required for IFR flight.
(d) Instrument flight rules. For IFR flight, the following instruments and equipment are required:
.....
(8) Gyroscopic pitch and bank indicator (artificial horizon).

(9) Gyroscopic direction indicator (directional gyro or equivalent).
Click to expand...
 
flyingron said:
In fact, ATC wouldn't have wanted reporting points if you were in uncontrolled airspace. Lack of radar service doesn't imply you aren't in controlled airspace or under control.

I've been flying through coastal NC and had them say "hey the radar is out at Seymour Johnson, we're going to have to put you back on an airway." It was then I realized what a boon the GNS480 was. You expand your flight plan and it gives you the ETAs for tall the intersections on the airway you're coming up on. Makes it easy to make the report. ATC was busy asking people to make specific reports, though what they were asking for were the mandatory reports if pilots these days knew how to operate in non-radar environments.
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The reporting point was in controlled airspace beyond the G in the account I gave.
 
Clip4 said:
The oil boom killed those Class G areas.
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No, it was the objective of permitting point-to-point RNAV navigation within the 48 states. It was a national agenda that was not focused on any particular state.
 
midlifeflyer said:
In 2021 in the US, the lack of Class G includes the inability to comply with several rules, making a real, complete uncontrolled IFR flight impractical. I did an article for IFR Magazine on it - subscription not required for this one.
Click to expand...

Great article, Mark. You did an excellent job of breaking this old hangar discussion into logical components. I agree with your conclusion as well.
 
Years ago, I wrote a blog post about how including an intermediate waypoint in a VFR flight plan and actually checking in when you fly over it could dramatically reduce the initial search area:

https://lahso.megginson.com/2010/08/14/why-checkpoints-matter/

This is based on simplistic assumptions that may not actually line up with SAR practices, but the net result was that simply adding a waypoint halfway along a 300 nm flightplan reduced the initial hypothetical search area from 9,500 nm² to 5,500 nm², and making a position report to flight services over that waypoint further reduced the hypothetical search area to 2,800 nm².

Of course, flight following, ADS-B out, or an InReach/Spot are even better, but it's astounding what a difference just that one position report can make.
 
I guess I was lucky to have plenty of experience with non-radar and uncontrolled IFR back in the '70s and '80s. Oh yeah, non-radar position reports and holds were a blast!

The term "upon entering controlled airspace" was a familiar part of an IFR clearance then and it sure made all this discussion better understood.

You'd have to try much harder nowadays to find all that class G. Those are some pretty remote areas...
 
David Megginson said:
Years ago, I wrote a blog post about how including an intermediate waypoint in a VFR flight plan and actually checking in when you fly over it could dramatically reduce the initial search area:

https://lahso.megginson.com/2010/08/14/why-checkpoints-matter/

This is based on simplistic assumptions that may not actually line up with SAR practices, but the net result was that simply adding a waypoint halfway along a 300 nm flightplan reduced the initial hypothetical search area from 9,500 nm² to 5,500 nm², and making a position report to flight services over that waypoint further reduced the hypothetical search area to 2,800 nm².

Of course, flight following, ADS-B out, or an InReach/Spot are even better, but it's astounding what a difference just that one position report can make.
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You can make a VFR position report anywhere. It doesn’t have to be over a ‘point’ that was on the Flight Plan or even have a Flight Plan filed. AIM 5-1-4 g. It’s been a few years and the Radar coverage is probably better now but I used to make these on Southern California to Las Vegas flights. There were large areas of no Radar at normal bug smasher cruising altitudes.

g. Although position reports are not required for
VFR flight plans, periodic reports to FAA FSSs along
the route are good practice. Such contacts permit
significant information to be passed to the transiting
aircraft and also serve to check the progress of the
flight should it be necessary for any reason to locate
the aircraft.
EXAMPLE−
1. Bonanza 314K, over Kingfisher at (time), VFR flight
plan, Tulsa to Amarillo.
2. Cherokee 5133J, over Oklahoma City at (time),
Shreveport to Denver, no flight plan.
 
I made a position report to FSS while on a VFR flight plan a few years ago. After being a bit confused the specialist took the position report. Not sure many people do this.
 
Arnold said:
View attachment 94413 Here is a bit of airspace where an such a flight may have been performed to get above a marine layer in the past few years. In fact the pilot may have done so using needle ball and airspeed to maintain straight and level. I've been told that the technique still works.
Click to expand...

If you want to continue climbing after getting above the layer that might be useful if you are a seaplane departing where the floor of Controlled Airspace is 1200. 1000/500/2000 and 3 applies. When you enter Controlled Airspace you must be 1000 feet above clouds. You can’t pull that off where the floor is 700.
 
Arnold said:
I made a position report to FSS while on a VFR flight plan a few years ago. After being a bit confused the specialist took the position report. Not sure many people do this.
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Doesn’t surprise me that it would have them scratching’ their head sayin’ WTF is this. Let’s say they refused to take it. Then give them a PIREP, could be just clear and smooth. Now there is a record of where you were and when you were there. If ya go down, it will show up when the INREQ is made.
 
luvflyin said:
You can make a VFR position report anywhere. It doesn’t have to be over a ‘point’ that was on the Flight Plan or even have a Flight Plan filed. AIM 5-1-4 g. It’s been a few years and the Radar coverage is probably better now but I used to make these on Southern California to Las Vegas flights. There were large areas of no Radar at normal bug smasher cruising altitudes.

g. Although position reports are not required for
VFR flight plans, periodic reports to FAA FSSs along
the route are good practice. Such contacts permit
significant information to be passed to the transiting
aircraft and also serve to check the progress of the
flight should it be necessary for any reason to locate
the aircraft.
EXAMPLE−
1. Bonanza 314K, over Kingfisher at (time), VFR flight
plan, Tulsa to Amarillo.
2. Cherokee 5133J, over Oklahoma City at (time),
Shreveport to Denver, no flight plan.
Click to expand...

Thanks for the reference. I remember being taught to make VFR position reports when I learned to fly thirty years ago.
 
luvflyin said:
You can make a VFR position report anywhere. It doesn’t have to be over a ‘point’ that was on the Flight Plan or even have a Flight Plan filed. AIM 5-1-4 g. It’s been a few years and the Radar coverage is probably better now but I used to make these on Southern California to Las Vegas flights. There were large areas of no Radar at normal bug smasher cruising altitudes.

g. Although position reports are not required for
VFR flight plans, periodic reports to FAA FSSs along
the route are good practice. Such contacts permit
significant information to be passed to the transiting
aircraft and also serve to check the progress of the
flight should it be necessary for any reason to locate
the aircraft.
EXAMPLE−
1. Bonanza 314K, over Kingfisher at (time), VFR flight
plan, Tulsa to Amarillo.
2. Cherokee 5133J, over Oklahoma City at (time),
Shreveport to Denver, no flight plan.
Click to expand...
Absolutely right. I used a flightplan waypoint in that old blog post to show how it might help even without the position report.

I don't make many long VFR cross-countries without flight following these days (plus my GTX 345 means my flight path is usually still on FlightAware), but the specialists at the Nav Canada FICs are still happy to take them down, and will sometimes ask me for a PIREP in return (if I'm somewhere less traveled).
 
Clip4 said:
Let’s put it this way, I have flown IFR in Class G airspace in IMC conditions 25 years ago.

Example one was after departing Minot on a SE bound flight. Upon entering Glass G airspace, ATC advised radar service terminated, report an intersection.

Example 2 was after filing an IFR flight plan leaving a public grass airport in ND. The flight was IMC until I contacted Minneapolis Center for clearance prior to entering Class E.

That was during a time when there literally may not have been any IFR flights over ND at various time of the day. The oil boom killed those Class G areas.
Click to expand...
Oddly enough, there is a big, new piece of class G in western ND, including the Killdeer Mountains, which brought me back to this thread. I don't know when this area popped up but I think it was in the past year. S25-9Y1 at non-oxygen altitudes is now more than 50% in class G airspace.
 
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