Question about an airway

[PPC1052]

Specifically, V53 going south from the VHP VOR, the MEA starts out as 2800, and then rises to 10,000 with a MOCA of 3000 south of HOUSE intersection. I am curious how this works if you are flying along at MEA (say you lost comms) and then cross HOUSE. I understand that you start climbing when you cross the intersection (since there is no MCA). But how do you pick up the nav signal that far north of the BQM VOR that low if the MEA is 10,000 and the MOCA is 3000? Maybe I am overlooking something, but I don't see any reason for such a disparity between the MOCA and MEA other than NAV reception. I am just curious. Thanks.

 

[genna]

If you were flying VOR navigation, you would be at higher altitude than MOCA here. I'm not an expert, but 1. You should know the route and ask for higher than 3000ft before HOUSE since you'd lose the VOR navigation. 2. Fly the heading you need while climbing as quickly as possible until MEA. In lost com you have to be at min MEA anyway. MOCA won't do it

MOCA is there as an altitude of "last resort" OR you can use it if you are using GPS navigation(may be smart to back it up, but that's a different topic)

 

[PPC1052]

If you were flying VOR navigation, you would be at higher altitude than MOCA here. I'm not an expert, but 1. You should know the route and ask for higher than 3000ft before HOUSE since you'd lose the VOR navigation.

Again, let's assume you lost comms such that you couldn't ask for higher.

Fly the heading you need while climbing as quickly as possible until MEA. In lost com you have to be at min MEA anyway. MOCA won't do it MOCA is there as an altitude of "last resort" OR you can use it if you are using GPS navigation(may be smart to back it up, but that's a different topic)

Yeah, I know. That's why I was asking. Climbing to 10,000 feet from 2800 with no Nav signal reception is what prompted my question.

 

[MauleSkinner]

Sounds like a perfect place to apply your dead reckoning skills.

 

[dtuuri]

But how do you pick up the nav signal that far north of the BQM VOR that low if the MEA is 10,000 and the MOCA is 3000? Maybe I am overlooking something, but I don't see any reason for such a disparity between the MOCA and MEA other than NAV reception.

A) V53 doesn't go to BQM.

B) Check the AFD:

LOUISVILLE N38º06.21´ W85º34.65´ NOTAM FILE LOU. (H) VORTAC 114.8 IIU Chan 95 298º 8.6 NM to Louisville Intl–Standiford Fld. 721/1E. VOR portion unusable: 285º–339º blo 10,000´ 340º–360º blo 4,000´ 340º–360º byd 20 NM blo 10,000´ 001º–093º blo 10,000´ RCO 119.5 122.1R 122.2 122.45 (LOUISVILLE RADIO)​

dtuuri

 

[PPC1052]

A) V53 doesn't go to BQM.

B) Check the AFD:

LOUISVILLE N38º06.21´ W85º34.65´ NOTAM FILE LOU. (H) VORTAC 114.8 IIU Chan 95 298º 8.6 NM to Louisville Intl–Standiford Fld. 721/1E. VOR portion unusable: 285º–339º blo 10,000´ 340º–360º blo 4,000´ 340º–360º byd 20 NM blo 10,000´ 001º–093º blo 10,000´ RCO 119.5 122.1R 122.2 122.45 (LOUISVILLE RADIO)​

dtuuri

Good catch. I guess it goes to IIU, but it goes right over BQM. Still, I have the same question. If you have to start climbing on course after the turn from HOUSE, can you expect to get the nav signal that low, and if not, how are you supposed to fly this?

 

[PPC1052]

Sounds like a perfect place to apply your dead reckoning skills.

IFR? How does that work?

 

[roncachamp]

Good catch. I guess it goes to IIU, but it goes right over BQM. Still, I have the same question. If you have to start climbing on course after the turn from HOUSE, can you expect to get the nav signal that low, and if not, how are you supposed to fly this?

You should be given 10,000 or higher well before HOUSE so that you'll be at or above that altitude at that point.

As a practical matter, the lowest enroute altitude that will be assigned for flights of significant distance will be the MEA/MIA/MVA, rounded up to the next cardinal altitude, plus 1000 feet so as not to shut down IFR operations at airports near the route, plus perhaps another 1000 feet for direction of flight. For the segment between VHP and HOUSE 5000 is more likely than 2800 and 11,000 should be assigned so as to permit the aircraft to cross HOUSE at or above 10,000.

V53 between HOUSE and IIU should have a GNSS RNAV MEA.

 

[genna]

Again, let's assume you lost comms such that you couldn't ask for higher.




Yeah, I know. That's why I was asking. Climbing to 10,000 feet from 2800 with no Nav signal reception is what prompted my question.

There is a practical matter here that I was referring to. In real life, you are not likely to be flying this at 3000 ft. unless you have GPS navigation for the exact reasons you stated. You would ask for higher altitude well before HOUSE, probably in the flight plan as you no doubt realized the potential problem here when you were planning the flight to begin with. But, in case this was all a major screw-up on your and controller parts, and you both missed the fact that you will lose navigation before being assigned MEA and all of a sudden you lost comms., you do have an HI, right? It does point to where you want to go? So yes, you will have to use your HI while climbing to regain VOR navigation. It's not ideal, but it's workable while you are trying to recover from a mistake and a mild emergency.

 

[PPC1052]

There is a practical matter here that I was referring to. In real life, you are not likely to be flying this at 3000 ft. unless you have GPS navigation for the exact reasons you stated. You would ask for higher altitude well before HOUSE, probably in the flight plan as you no doubt realized the potential problem here when you were planning the flight to begin with. But, in case this was all a major screw-up on your and controller parts, and you both missed the fact that you will lose navigation before being assigned MEA and all of a sudden you lost comms., you do have an HI, right? It does point to where you want to go? So yes, you will have to use your HI while climbing to regain VOR navigation. It's not ideal, but it's workable while you are trying to recover from a mistake and a mild emergency.

Thanks for your thoughts. It does seem unlikely to have been assigned 2800, but I could certainly see something like 5000. Still, that's a 10 minute climb that would seem to have questionable navigation, and I was just wondering what's expected and possible should I find myself in such a situation sometime. The good thing is that this is not a particular mountainous area, and I think there is good radar coverage.

 

[luvflyin]

IFR? How does that work?

Ya want a course of 152, so fly heading 152. If there are winds, adjust. There actually are some airways with dead reckoning segments. From a practical standpoint my guess is that MEA is not really issue there because of Radar coverage. From the purist point of view it's simple. If your aircraft performance does not allow you to comply with the Minimum Altitudes, neither file for nor accept a clearance on those segments of that airway.

 

[MauleSkinner]

IFR? How does that work?

Just like it does VFR.

If, as the OP asked, you find yourself without comm and electronic navigation ability through some combination of error and misfortune, you either fall back on DR or you flounder aimlessly.

Choose wisely.

 

[genna]

Thanks for your thoughts. It does seem unlikely to have been assigned 2800, but I could certainly see something like 5000. Still, that's a 10 minute climb that would seem to have questionable navigation, and I was just wondering what's expected and possible should I find myself in such a situation sometime. The good thing is that this is not a particular mountainous area, and I think there is good radar coverage.

Sorry for sarcasm there ... I was just trying to convey that you shouldn't accept a clearance that may put you in a spot like that. And that HI/compass is there as a navigational equipment for a reason. It may not be the best, but it works nevertheless. If the area had more obstacles, I would be even more careful with planning and accepting such a low clearance.

However, as it stands, with a 7600, you can start climbing before HOUSE and ATC will route traffic around you. If you have to fly with HI only and get somewhat off course, it will not be that much of a problem(as long as you can reacquire it reasonably soon).

 

[genna]

FWIW, I thought it was a good question.. Made me think about paying attention to my planned altitude requests

 

[dtuuri]

However, as it stands, with a 7600, you can start climbing before HOUSE...

Pardon moi, under what authority can you do that? Certainly not 91.185.

dtuuri

 

[genna]

Pardon moi, under what authority can you do that? Certainly not 91.185.

dtuuri

There is no authority. Technically and legally you need to wait until HOUSE to start your climb. But since you are expecting to be well below MEA and VOR navigation altitude, I suspect it is not going to get you in a serious trouble if you start climbing a little bit before. Potentially less trouble than if you deviate from course significantly by flying just by Heading Indicator for a longer time. Just my .02 here, not a legal opinion. Probably wrong too . This probably depends a lot on whether you are in radar coverage or not.. If not, I wouldn't do that.

 

[roncachamp]

Pardon moi, under what authority can you do that? Certainly not 91.185.

Under 91.3(b).

 

[PPC1052]

Just like it does VFR.

My mistake. I was reading DR, but thinking pilotage. Mea culpa.

 

[bobmrg]

Specifically, V53 going south from the VHP VOR, the MEA starts out as 2800, and then rises to 10,000 with a MOCA of 3000 south of HOUSE intersection. I am curious how this works if you are flying along at MEA (say you lost comms) and then cross HOUSE. I understand that you start climbing when you cross the intersection (since there is no MCA). But how do you pick up the nav signal that far north of the BQM VOR that low if the MEA is 10,000 and the MOCA is 3000? Maybe I am overlooking something, but I don't see any reason for such a disparity between the MOCA and MEA other than NAV reception. I am just curious. Thanks.

Without looking at a chart: MOCA applies only within 22nm of a VOR. Is that the case here?

Bob Gardner

 

[PPC1052]

Without looking at a chart: MOCA applies only within 22nm of a VOR. Is that the case here?

Bob Gardner

I presume it does. Which is why I am thinking that climbing southbound from HOUSE would be required to get the VOR signal. There is a bend in the airway at HOUSE, so that is obviously the changeover point.

 

[luvflyin]

........However, as it stands, with a 7600, you can start climbing before HOUSE and ATC will route traffic around you. If you have to fly with HI only and get somewhat off course, it will not be that much of a problem(as long as you can reacquire it reasonably soon).

You should be squawkin 7700 if your gonna climb early based on 91.3 (b). If your just NORDO, no climb higher than the MEA, last assigned or last expected for the segment before HOUSE would be appropriate.

 

[Palmpilot]

Good catch. I guess it goes to IIU, but it goes right over BQM. Still, I have the same question. If you have to start climbing on course after the turn from HOUSE, can you expect to get the nav signal that low, and if not, how are you supposed to fly this?

My understanding is that if you couldn't receive IIU if you waited until HOUSE to start your climb from the previous MEA, then they would have published a minimum crossing altitude at HOUSE. And they flight check published altitudes on a regular basis to make sure that the relevant navaids are usable and within tolerance at the required altitudes.

 

[PPC1052]

My understanding is that if you couldn't wait until HOUSE to start your climb from the previous MEA and receive IIU, then they would have published a minimum crossing altitude at HOUSE. And they flight check published altitudes on a regular basis to make sure that the relevant navaids are usable and within tolerance at the required altitudes.

Interesting thought, and one that I initially had. But I wonder why the 11,000 foot MEA, with a MOCA of only 3000 if it isn't necessary for reception.

 

[aterpster]

My guess there is no MCA at HOUSE because it isn't an obstacle clearance issue. But, southbound, if you start the climb at HOUSE you will likely lose VOR reception. I don't really know what the FAA design and implementation policy is on these failing VORS that adversely affect MEAs.

 

[Palmpilot]

My guess there is no MCA at HOUSE because it isn't an obstacle clearance issue. But, southbound, if you start the climb at HOUSE you will likely lose VOR reception. I don't really know what the FAA design and implementation policy is on these failing VORS that adversely affect MEAs.

Well, your guess is probably better than mine!

 

[PPC1052]

My guess there is no MCA at HOUSE because it isn't an obstacle clearance issue. But, southbound, if you start the climb at HOUSE you will likely lose VOR reception. I don't really know what the FAA design and implementation policy is on these failing VORS that adversely affect MEAs.

Oh, no. You were my best hope to solve the mystery. Oh, well. Thanks anyway.

 

[flyingron]

IFR? How does that work?

Same way it works VFR. Estimate time and heading and fly that until you get some way of fixing your position.

 

[dtuuri]

Oh, no. You were my best hope to solve the mystery. Oh, well. Thanks anyway.

I don't see where there is any mystery. You plan the flight, see the restriction when using V53, flight plan in accordance with it, don't accept any clearances that are contrary to it and make your flight. Then if you lose comms you will never be without navigational guidance. It's an IFR pilot's mindset (hint).

dtuuri

 

[aterpster]

I don't see where there is any mystery. You plan the flight, see the restriction when using V53, flight plan in accordance with it, don't accept any clearances that are contrary to it and make your flight. Then if you lose comms you will never be without navigational guidance. It's an IFR pilot's mindset (hint).

dtuuri

I believe the "mystery" is the lack of an MCA at HOUSE and the resultant reception problem if you cross HOUSE well below 10,000, perhaps as low as 3,000.

 

[dtuuri]

I believe the "mystery" is the lack of an MCA at HOUSE and the resultant reception problem if you cross HOUSE well below 10,000, perhaps as low as 3,000.

I'd guess an MCA is an original design limitation whereas unusable radials in this case are temporary maintenance limitations that have been long-standing enough to move from NOTAMS to A/FD.

dtuuri

 

[PPC1052]

I believe the "mystery" is the lack of an MCA at HOUSE and the resultant reception problem if you cross HOUSE well below 10,000, perhaps as low as 3,000.

Yes. This. This exactly. This is what I was trying to ask about in my OP, although not very artfully.

 

[PPC1052]

You plan the flight, see the restriction when using V53, flight plan in accordance with it, don't accept any clearances that are contrary to it and make your flight. Then if you lose comms you will never be without navigational guidance. It's an IFR pilot's mindset (hint).

dtuuri

Sure. I get that. But I want to know what's happening here so I can get a better understanding of the FAA's thinking process.

 

[aterpster]

I'd guess an MCA is an original design limitation whereas unusable radials in this case are temporary maintenance limitations that have been long-standing enough to move from NOTAMS to A/FD.

dtuuri

In order for the MEA to be its present 10,000' an amended rule had to be issued under Part 95. It would have been easy to have included an MCA in that same amendment. But, Paragraph 1730 of TERPs states that an MCA is to assure obstacle clearance. That isn't the issue in this situation. I guess sitting at the big desk some "friendly" decided a pilot should be able to figure out on his own that he must be at (or above) 10,000 crossing HOUSE SE bound.

Also, why didn't they include a G MEA of 3,000? I guess that would have made too much sense.

 

[Palmpilot]

In the absence of an MCA, the mystery for me is why does 91.177(b) say that the climb to the new MEA shall begin after passing the fix, if navaid reception is not guaranteed?

"§91.177 Minimum altitudes for IFR operations...​

"(b) Climb. Climb to a higher minimum IFR altitude shall begin immediately after passing the point beyond which that minimum altitude applies, except that when ground obstructions intervene, the point beyond which that higher minimum altitude applies shall be crossed at or above the applicable MCA."​

 

[aterpster]

In the absence of an MCA, the mystery for me is why does 91.177(b) say that the climb to the new MEA shall begin after passing the fix, if navaid reception is not guaranteed?

"§91.177 Minimum altitudes for IFR operations...​

"(b) Climb. Climb to a higher minimum IFR altitude shall begin immediately after passing the point beyond which that minimum altitude applies, except that when ground obstructions intervene, the point beyond which that higher minimum altitude applies shall be crossed at or above the applicable MCA."​

When 91.177 was written VOR stations were not old and losing performance.

 

[denverpilot]

When 91.177 was written VOR stations were not old and losing performance.

Is it really "performance loss" @aterpster ?

The on the ground at the site, maintenance folks, that I've talked to, say nothing materially has changed, the equipment either works or it doesn't.

They say the flight check folks just got around to seeing what actually worked in a more stringent way, and marked all sorts of stuff folks used for decades as "unusable".

 

[aterpster]

Is it really "performance loss" @aterpster ?

The on the ground at the site, maintenance folks, that I've talked to, say nothing materially has changed, the equipment either works or it doesn't.

They say the flight check folks just got around to seeing what actually worked in a more stringent way, and marked all sorts of stuff folks used for decades as "unusable".

I don't have the answer to that. You've got one FAA disputing another FAA. Fact is, the MEA is now 10,000 feet over an area that should have an MEA of 3,000. There is a VOR IAP at a local airport that had its minimum raised by 400 feet for similar reasons. Seems like flight inspection holds the trump card. ("trump" with a lower-case "t")

 

[PPC1052]

One more question: if the issue at HOUSE is reception (and checking the A/FD entry for KSDF it seems that it is), why no MRA?

 

[dtuuri]

One more question: if the issue at HOUSE is reception (and checking the A/FD entry for KSDF it seems that it is), why no MRA?

I see just two possibilities:

1) It was an oversight

2) It's a temporary situation that doesn't require a flight check.

I don't know the answer, but if you report it and find out please let us know.

dtuuri