Flying at MOCA to airport without IAP

[John Collins]

Azure, back in the day, dual VOR's was precision. We did a lot of locating airports by knowing their position via VOR radial intersections that we found by using our chart. DME had an accuracy of about 2 NM and almost no one had it. It was a window washer needle movement on an indicator, see the attached graphic.



We practiced IFR navigation to an arbitrary intersection from a random location as an IFR training exercise. It did not have much practical use, but was helpful in teaching orientation and situational awareness. Actual IFR was often VOR to VOR not along airways when it suited our purposes.

If the terms were being invented today, we would have really really high precision (ILS and LPV) and precision approaches (LNAV). Back in the day, they meant it when they named the VOR and NDB approaches as non precision. These procedures were only intended to get you underneath the cloud deck and in the same county as the airport. One had to look both to the left and right and needed at least 1 mile visibility to have any chance of spotting the runway.

 

[azure]

Now, now. When I got my instrument rating, using a plotter and E6B to draw checkpoints and compute groundspeeds and ETAs was standard operating procedure. Just because RNAV came along doesn't negate the use of those techniques.

I've done that too -- as a student pilot in a /U 172 trainer trying to get close to TVC during an airshow, without violating the TFR. I know how to do it -- I'm not an "old salt" but I learned how to navigate before the "magenta line" was common equipment. In that case I made sure I accounted for all reasonable errors and chose my plotted course to never get closer than about 8 nm from the edge of the TFR. But this was VFR, the worst that could have happened was my CFI would have gotten a 709 ride and I would have gotten a tongue lashing from him.

Someone mentioned non-precision approaches -- the worst ones I know of are 20 plus nm from the VOR and yes, they basically just get you to the neighborhood of the airport. But they're flight tested for obstacles so if your equipment is within spec, you shouldn't be in any danger of hitting anything. -D-> to an airport in the mountains without an IAP is the scenario I've had doubts about.

Steven, I was asking about the ATC-determined minimum IFR altitude.

 

[roncachamp]

Steven, I was asking about the ATC-determined minimum IFR altitude.

On a cruise clearance to an airport without an IAP ATC would issue the predetermined MVA/MIA; "Waco 29E cruise xxxx". The pilot could then descend to whatever altitude he had determined was consistent with FAR 91.177.

 

[dtuuri]

Someone mentioned non-precision approaches -- the worst ones I know of are 20 plus nm from the VOR and yes, they basically just get you to the neighborhood of the airport. But they're flight tested for obstacles so if your equipment is within spec, you shouldn't be in any danger of hitting anything. -D-> to an airport in the mountains without an IAP is the scenario I've had doubts about.

Right, so when we decide to go where Uncle Sam hasn't gone before us, we just have to be real careful and not expect all the customary protections. What's wrong with that?

dtuuri

 

[Henning]

Should be OROCA if not on an airway, sorry. But note the wording about blundering around looking for the airport. If you are 4 nm off and there are obstacles nearby, and you lose situational awareness (easy to do if the vis is marginal), could be a quick way to go.

Yes, none of this stuff is required procedure on the IR PTS, but it's an option for people who decide they want to. There are inherent risks along with aggravating and mitigating factors.

 

[Palmpilot]

Should be OROCA if not on an airway, sorry. But note the wording about blundering around looking for the airport. If you are 4 nm off and there are obstacles nearby, and you lose situational awareness (easy to do if the vis is marginal), could be a quick way to go.

"Blundering around" is definitely not recommended! When you're flying a VOR radial to an airport, if you reach the predetermined azimuth and range without seeing the airport, it would be neither legal nor safe, IMO, to depart from your predetermined radial in search of the airport, unless you were in conditions that were good enough to cancel IFR both legally and safely. If conditions were such that you needed to remain IFR, you would have reached your clearance limit, so unless you had been given a specific Plan B by ATC, I think you would be required to enter a holding pattern while you contacted ATC and requested a clearance to your alternate. In any case, the pilot needs to have thought through a safe alternate plan for the case where the airport does not come into view.

I do share your concern for the risks of pushing the limits of VOR technology in the mountains. If you're using a VOR with a 40 nm service volume, navigating to an airport that is right at the 40 nm limit would mean that you could be 4 nm off, by my calculations. How much protection you get from the 2000 AGL buffer in designated mountainous areas is going to depend on how steep the mountain slopes are, so clearly, good judgment is required.

 

[azure]

On a cruise clearance to an airport without an IAP ATC would issue the predetermined MVA/MIA; "Waco 29E cruise xxxx". The pilot could then descend to whatever altitude he had determined was consistent with FAR 91.177.

Okay, thanks. Though I'm not sure how the predetermined MVA or MIA is actually determined, it's pretty obvious that the 91.177(a)(2)(i) altitude is a sticky wicket.

 

[Palmpilot]

That specific wording has only been around since 2007 when it was updated to account for GPS and RNAV. Prior to that time, it read as:



Since you are older than dirt, I must have been born before continental drift started.

Wouldn't "older than dirt" imply that he pre-dated the formation of Earth's crust?

Or since there is dust in outer space, would it imply that he pre-dated the formation of the solar system?

 

[Palmpilot]

Okay, thanks. Though I'm not sure how the predetermined MVA or MIA is actually determined, it's pretty obvious that the 91.177(a)(2)(i) altitude is a sticky wicket.

And the topographic detail on sectionals is somewhat crude, especially in the mountains.

 

[azure]

Right, so when we decide to go where Uncle Sam hasn't gone before us, we just have to be real careful and not expect all the customary protections. What's wrong with that?

Not saying there's anything wrong with it operationally, as long as you have the discipline to pad your 91.177(a)(2)(i) 4 nm from the course as much as is prudent, and immediately execute your homegrown "missed approach" procedure if you don't see the airport.

Whether it's actually legal is my question. It's stretching the leash far enough out that I wonder if Ron isn't right, that's all. It wouldn't surprise me if this were another one of those things that lots of people have done for years but is against the FAA's not-quite-explicitly spelled out interpretation of their own regs... kinda like navigating direct to an intersection from a random point in a /U or /A aircraft.

 

[azure]

"Blundering around" is definitely not recommended! When you're flying a VOR radial to an airport, if you reach the predetermined azimuth and range without seeing the airport, it would be neither legal nor safe, IMO, to depart from your predetermined radial in search of the airport, unless you were in conditions that were good enough to cancel IFR both legally and safely. If conditions were such that you needed to remain IFR, you would have reached your clearance limit, so unless you had been given a specific Plan B by ATC, I think you would be required to enter a holding pattern while you contacted ATC and requested a clearance to your alternate. In any case, the pilot needs to have thought through a safe alternate plan for the case where the airport does not come into view.

That's a good point. In controlled airspace, you need a clearance to proceed beyond your CL unless you're lost comm. Generally there wouldn't be any "protected airspace" beyond what you've determined is 91.177-safe, so you'd have to roll your own holding pattern too.

 

[Palmpilot]

Not saying there's anything wrong with it operationally, as long as you have the discipline to pad your 91.177(a)(2)(i) 4 nm from the course as much as is prudent, and immediately execute your homegrown "missed approach" procedure if you don't see the airport.

Whether it's actually legal is my question. It's stretching the leash far enough out that I wonder if Ron isn't right, that's all. It wouldn't surprise me if this were another one of those things that lots of people have done for years but is against the FAA's not-quite-explicitly spelled out interpretation of their own regs... kinda like navigating direct to an intersection from a random point in a /U or /A aircraft.

If the FAA published that interpretation, the case for abiding by it would be much stronger, IMO.

One thing to keep in mind, though, is that Cap'n Ron has acknowledged that it would be legal to do what we're talking about if you filed/were cleared to your predetermined radial and distance as the last waypoint before the airport. I don't think doing so would change the safety aspects of the operation.

 

[Palmpilot]

That's a good point. In controlled airspace, you need a clearance to proceed beyond your CL unless you're lost comm. Generally there wouldn't be any "protected airspace" beyond what you've determined is 91.177-safe, so you'd have to roll your own holding pattern too.

I'll look it up, but I believe the holding pattern in that situation is specified by regulation or in the AIM, i.e., not roll-your-own.

 

[azure]

OK, admittedly I have lost interest in this thread and grown weary of purported experts with their legal quotes and purported FAA connections (if they only knew...) I have stopped actively monitoring this thread. With that said, you lost me with this IFR+VFR commentary above. Sorry but I went to public High School. I can't figure out if you were asking a question or just making a comment.

In case you check back in, I was referring to the Chief Counsel's letter to John Goodish. It's a side issue, but I'll try to attach it to this post FYI. Since you're not interested in legal details, you probably won't care, but someone else might.

 

[azure]

I'll look it up, but I believe the holding pattern in that situation is specified by regulation or in the AIM, i.e., not roll-your-own.

Which might or might not be safe to fly if your VOR receiver is close to the edge of tolerance, depending on the exact location and distance of the rocks.

 

[Palmpilot]

Which might or might not be safe to fly if your VOR receiver is close to the edge of tolerance, depending on the exact location and distance of the rocks.

Agreed. That is one of many reasons why legal does not necessarily equal safe, especially in the mountains, and it is one of the things to be considered when making go/no-go decisions.

 

[roncachamp]

Okay, thanks. Though I'm not sure how the predetermined MVA or MIA is actually determined, it's pretty obvious that the 91.177(a)(2)(i) altitude is a sticky wicket.

Through a blend of art and science. The science part is determined by terrain, obstacles, and controlled airspace. The art is creating areas of size and shape that comply with the science in the most advantageous manner operationally.

 

[MyassisDragon]

As a practical matter, assuming my aircraft was /U, I would file a route that included ESC V271 MBL. I would file my destination as 2P2. I would choose an alternate suitable for my equipment.

Along the airway, I would request the MOCA and fly it until either seeing 2P2 or needing to climb higher to the MEA. On spotting 2P2, I would report it in sight and request the visual if it was doable. If I did not spot the airport prior to needing to climb, I would continue on to my clearance limit and request an appropriate route to my alternate.

For what its worth ( 2 cents maybe) I fly in and out of an airport lacking procedures (sometimes /U sometimes /G) and in the past this is exactly what I would do on a IFR flight plan. With the exception of going direct VIA vectors (on /U) from ATC, and I never seem to request the MOCA they just step me down to it.

They always seem know my intentions of a visual approach and usually vector to it and ask me to report airport in sight. If not in sight they will vector me to the ILS of the next airport over, being my alternate (Im lucky its only 5 miles south)

 

[azure]

One thing to keep in mind, though, is that Cap'n Ron has acknowledged that it would be legal to do what we're talking about if you filed/were cleared to your predetermined radial and distance as the last waypoint before the airport. I don't think doing so would change the safety aspects of the operation.

I thought he said you could file to the radial/distance coordinates. Then that point, not the airport, would be your clearance limit. You couldn't land without being cleared for the visual, or canceling IFR after reaching VMC. So while I agree that the actual safety considerations for a pilot intending to land that way would be the same, I can imagine that the FAA might (obviously in an unpublished internal interpretation) consider a cruise clearance to the airport in that circumstance to be too loose a leash.

 

[Palmpilot]

I'll look it up, but I believe the holding pattern in that situation is specified by regulation or in the AIM, i.e., not roll-your-own.

This looks like what I was thinking of, but I see now that the context is a clearance to a fix other than the destination airport, so I'm not sure that it's applicable to this situation after all. And certainly, in the mountains, one could not assume it would be a safe plan B without carefully examining any terrain issues that could come into play in a hold.

[Emphasis added:]

AIM 5-3-8 Holding

a. Whenever an aircraft is cleared to a fix other
than the destination airport and delay is expected, it
is the responsibility of the ATC controller to issue
complete holding instructions (unless the pattern is
charted), an EFC time and best estimate of any
additional en route/terminal delay.

NOTE−
Only those holding patterns depicted on U.S. government
or commercially produced (meeting FAA requirements)
low/high altitude enroute, and area or STAR charts should
be used.

b. If the holding pattern is charted and the
controller doesn’t issue complete holding instructions,
the pilot is expected to hold as depicted on the
appropriate chart. When the pattern is charted, the
controller may omit all holding instructions except
the charted holding direction and the statement AS
PUBLISHED; e.g., HOLD EAST AS PUBLISHED.
Controllers must always issue complete holding
instructions when pilots request them.

c. If no holding pattern is charted and holding
instructions have not been issued, the pilot should ask
ATC for holding instructions prior to reaching the fix.
This procedure will eliminate the possibility of an
aircraft entering a holding pattern other than that
desired by ATC. If unable to obtain holding
instructions prior to reaching the fix (due to
frequency congestion, stuck microphone, etc.), then
enter a standard pattern on the course on which the
aircraft approached the fix and request further
clearance as soon as possible. In this event, the
altitude/flight level of the aircraft at the clearance
limit will be protected so that separation will be
provided as required...

j. Holding pattern airspace protection is based on
the following procedures.

1. Descriptive Terms.

(a) Standard Pattern. Right turns
(See FIG 5−3−3.)

(b) Nonstandard Pattern. Left turns...​

 

[dtuuri]

...unless you had been given a specific Plan B by ATC, I think you would be required to enter a holding pattern...

Being an off-airway destination you might have to hold until fuel exhaustion. There's no guarantee you can reach ATC with your radio. Better to get a cruise clearance with a plan B in advance. This is all covered in my first IFR Tutorial, An IFR Pilot's Mindset.

dtuuri

 

[Palmpilot]

I thought he said you could file to the radial/distance coordinates.

I agree.

Then that point, not the airport, would be your clearance limit.

That's not my recollection of what was said, but I'll look for the posts involved.

You couldn't land without being cleared for the visual, or canceling IFR after reaching VMC.

I think everyone agrees that, barring an emergency or lost com, you can't land at an airport that has no published instrument approach procedure unless you are cleared for a visual approach or you cancel IFR, whether it's your clearance limit or not.

So while I agree that the actual safety considerations for a pilot intending to land that way would be the same, I can imagine that the FAA might (obviously in an unpublished internal interpretation) consider a cruise clearance to the airport in that circumstance to be too loose a leash.

Based on the experiences that both pilots and controllers in this thread are reporting, controllers don't seem to have a problem with it.

 

[Palmpilot]

Being an off-airway destination you might have to hold until fuel exhaustion. There's no guarantee you can reach ATC with your radio. Better to get a cruise clearance with a plan B in advance. This is all covered in my first IFR Tutorial, An IFR Pilot's Mindset.

In that case, the lost com rules would seem to apply, and they don't appear to have any prohibition against flying to your alternate if your destination is socked in.

 

[azure]

That's not my recollection of what was said, but I'll look for the posts involved.

I'm pretty sure he didn't say that a /U or /A aircraft could accept an off-airway clearance direct to an airport, so I'm not sure why you're making a distinction between what you file to and what your clearance limit is.

I think everyone agrees that, barring an emergency or lost com, you can't land at an airport that has no published instrument approach procedure unless you are cleared for a visual approach or you cancel IFR, whether it's your clearance limit or not.

Or a cruise clearance to the airport, which is the longest leash scenario of any that we've been discussing and the one that IMO the FAA is likeliest to take a dim view of.

Based on the experiences that both pilots and controllers in this thread are reporting, controllers don't seem to have a problem with it.

Agreed (emphasis added, since FAA internal opinion might differ).

I'll also add that I wouldn't be TOO worried either about the FAA busting me for violating one of their unpublished internal interpretations of the regs. But I'd make damn sure I didn't do anything to call attention to myself.

 

[Palmpilot]

That's not my recollection of what was said, but I'll look for the posts involved.

Found them.

The relevant excerpt:

...

However if the pilot is concerned about the possibility that the FAA might deem it illegal to file to an airport that the pilot is planning to find via VOR radials and/or DME distance that he determined himself, why not just file that radial crossing and/or DME distance as the final fix before the airport?

Why not, indeed? And I so suggested above.

When I wrote "the final fix before the airport," I did not mean to imply that the airport was not the clearance limit. I checked the earlier post that he seemed to be referring to, but it does not specify what he was considering the clearance limit to be:

You cannot legally use a DME cut or VOR radial to identify a point not defined by that DME cut or VOR radial. One could legally obtain a clearance direct to ESC161021 (ESC 161 radial/21 DME fix), but a) that's not the same as being cleared direct 2P2, and b) you'd need a DME receiver which the OP doesn't have. With only VOR, you could obtain a clearance from ESC via the ESC 161 radial to the intersection of that radial with the MNM 068 radial (assuming there are no published or NOTAM restrictions on that radial), but again, that is not the same as being cleared direct to 2P2. This may seem like semantics, but it is the rule.

 

[peerlesscowboy]

......................, it's pretty obvious that the 91.177(a)(2)(i) altitude is a sticky wicket.

"sticky wicket"? really, it just takes a little pre-flight planning......and well maintained and aligned navigation equipment.

 

[Palmpilot]

I'm pretty sure he didn't say that a /U or /A aircraft could accept an off-airway clearance direct to an airport, so I'm not sure why you're making a distinction between what you file to and what your clearance limit is.

I didn't mean to imply such a distinction. What I was trying to say is that the last fix in the route section of your flight plan could be your predetermined VOR radial-crossing fix or radial-and-distance fix, but that you would still put the airport in the destination section. ATC has never given me a clearance limit other than what I have put in the destination section, regardless of what fixes I put in the route section.

I'll also add that I wouldn't be TOO worried either about the FAA busting me for violating one of their unpublished internal interpretations of the regs. But I'd make damn sure I didn't do anything to call attention to myself.

Controllers would be the ones most likely to report you to the FSDO, and they seem to think that clearing a /U or /A aircraft direct to an airport within the service volume of a VOR is legal.

As for attracting attention to myself, my goal is to live long enough to attend the hearing. Until I hear about the FAA bringing an enforcement action against the pilot of a /U or /A aircraft for accepting a direct clearance from a VOR to an airport within its service volume, I don't plan on worrying about it at all.

 

[dtuuri]

In that case, the lost com rules would seem to apply, and they don't appear to have any prohibition against flying to your alternate if your destination is socked in.

So then, we agree that holding is not going to be required after all?

dtuuri

 

[dtuuri]

...a cruise clearance to the airport, which is the longest leash scenario of any that we've been discussing and the one that IMO the FAA is likeliest to take a dim view of.

You've gotta be kidding. You folks have a nice time dancing around the obvious. Bye.

dtuuri

 

[azure]

When I wrote "the final fix before the airport," I did not mean to imply that the airport was not the clearance limit. I checked the earlier post that he seemed to be referring to, but it does not specify what he was considering the clearance limit to be:

That's the post I was thinking of too, thanks for looking it up. I'm pretty sure he is considering the point in space defined by the navaid radial(s) and/or distance to be the clearance limit. I've bolded the parts that read that way to me. Maybe Ron will weigh in again...

You cannot legally use a DME cut or VOR radial to identify a point not defined by that DME cut or VOR radial. One could legally obtain a clearance direct to ESC161021 (ESC 161 radial/21 DME fix), but a) that's not the same as being cleared direct 2P2, and b) you'd need a DME receiver which the OP doesn't have. With only VOR, you could obtain a clearance from ESC via the ESC 161 radial to the intersection of that radial with the MNM 068 radial (assuming there are no published or NOTAM restrictions on that radial), but again, that is not the same as being cleared direct to 2P2. This may seem like semantics, but it is the rule.

 

[Palmpilot]

So then, we agree that holding is not going to be required after all?

Since the context of the AIM passage I was thinking of is a clearance limit other than the destination airport, and that's not the situation here, I will defer to your greater knowledge and experience in saying it is not required by the FAA, although I can think of situations where it could be required for safety reasons (for example, climbing in a holding pattern to get out of a mountain valley).

 

[azure]

As for attracting attention to myself, my goal is to live long enough to attend the hearing. Until I hear about the FAA bringing an enforcement action against the pilot of a /U or /A aircraft for accepting a direct clearance from a VOR to an airport within its service volume, I don't plan on worrying about it at all.

The closest comparison I can think of is filing IFR with "VFR" as the altitude. There is no regulation against it, there is no published interpretation that forbids it specifically (because Goodish totally bolloxed the question, and the procedure he asked about actually generates an IFR strip), but I know from experience that there are FAA attorneys trying to scare people out of filing that way, apparently on the basis of Goodish. If I wasn't IFR legal would I let that keep me from doing it? No, but I would expect it to come up in the hearing if I called attention to myself, and I don't have that much faith that the administrative law courts will contradict an FAA internal interpretation that goes against common practice. So, I make sure that I don't do anything that might lead to that hearing.

 

[Palmpilot]

That's the post I was thinking of too, thanks for looking it up. I'm pretty sure he is considering the point in space defined by the navaid radial(s) and/or distance to be the clearance limit. I've bolded the parts that read that way to me. Maybe Ron will weigh in again...

I interpreted the bolded sections as dealing with how the cleared route was specified, not as changing the clearance limit. Whether he feels it worthwhile to clarify his thinking on that point is, of course, up to him. Enough very knowledgeable and experienced folks have weighed in on the subject that I'm not going to lose sleep over it either way.

 

[Palmpilot]

The closest comparison I can think of is filing IFR with "VFR" as the altitude. There is no regulation against it, there is no published interpretation that forbids it specifically (because Goodish totally bolloxed the question, and the procedure he asked about actually generates an IFR strip), but I know from experience that there are FAA attorneys trying to scare people out of filing that way, apparently on the basis of Goodish. If I wasn't IFR legal would I let that keep me from doing it? No, but I would expect it to come up in the hearing if I called attention to myself, and I don't have that much faith that the administrative law courts will contradict an FAA internal interpretation that goes against common practice. So, I make sure that I don't do anything that might lead to that hearing.

For me, the existence and public availability of the chief counsel opinion is enough, whatever it's imperfections may be. I consider those to be much more authoritative than opinions that have been removed from public access because the chief counsel apparently didn't want to be bound by them.

 

[B350ATP]

I think the term "chief counsel" has been mentioned more on this thread than "MOCA" which was part of OP question in the first place

 

[Palmpilot]

Touché!

 

[RotorAndWing]

I think the term "chief counsel" has been mentioned more on this thread than "MOCA" which was part of OP question in the first place

Touché!

Once you reach "maven" status then you are blessed at the alter of the Chief Counsel........

 

[B350ATP]

In case you check back in, I was referring to the Chief Counsel's letter to John Goodish. It's a side issue, but I'll try to attach it to this post FYI. Since you're not interested in legal details, you probably won't care, but someone else might.

Thank you for the attachment. Is it just me or is the FAA letter fairly "common sense" information ?

 

[Palmpilot]

Thank you for the attachment. Is it just me or is the FAA letter fairly "common sense" information ?

I think the letter is baloney from start to finish. It comes perilously close to establishing a "thoughtcrime." (Fortunately for me, filing an IFR flight plan to facilitate getting VFR flight following is not something that ever seemed all that useful to me.)

Here's a previous discussion on the subject:

http://www.pilotsofamerica.com/forum/showthread.php?p=1107628#post1107628

 

[B350ATP]

I think the letter is baloney from start to finish. It comes perilously close to establishing a "thoughtcrime." (Fortunately for me, filing an IFR flight plan to facilitate getting VFR flight following is not something that ever seemed all that useful to me.)

Here's a previous discussion on the subject:

http://www.pilotsofamerica.com/forum/showthread.php?p=1107628#post1107628

I agree 100%