Top Altitude lower than MEA on SID

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djm181

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I am trying to understand the altitudes on the LURIC2 departure from KSGR.

https://skyvector.com/files/tpp/1509/pdf/05537LURIC.PDF

What is the meaning of the "Top Altitude: 4000" annotation at the top of the plate?

I assume the large difference between MOCAs and MEAs along the route is to provide clearance over the arriving traffic, so I'm unclear what Top Altitude means, and can't find any reference to it in the AIM other than in 5-2-8 regarding Climb via.

Can anyone explain this?
 
Read the text on page 2.

You are expected to claim and maintain 4000.

The text is the actual "procedure." The diagram is a visual aid.

This is an RNAV procedure, so the MEAs are the numbers with asterisks. Assuming you have GPS.
 
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Thanks - I watched the video, which was informative.

MAKG1 said:
This is an RNAV procedure, so the MEAs are the numbers with asterisks. Assuming you have GPS.
Click to expand...

I assume you are referencing 91.177(1) here where the MOCA is your legal minimum, but doesn't technically become the MEA.

So I see no problem filing this SID with a filed altitude of 7000.
 
MAKG1 said:
Read the text on page 2.

You are expected to claim and maintain 4000.

The text is the actual "procedure." The diagram is a visual aid.

This is an RNAV procedure, so the MEAs are the numbers with asterisks. Assuming you have GPS.
Click to expand...

MEA's and MOCA's on SID's wasn't passing the logic test with me. That is what they are calling it on the Legend for DP charts. The asterisks are the MOCA's. The other altitudes are MEA's which at one time guaranteed obstruction and navaid reception on an airway. These altitudes, ranging from 3100 up to 12,000 in the flatlands obviously have nothing to do with that. TERPS guys??? what's up with MEA's on on SID's???
 
This is an RNAV SID but you can do it using any RNAV 1 equipment, which doesn't necessarily mean GPS. If you have DME/DME/IRU RNAV then you will be picking up IAH and DAS vortacs to identify MUSIQ, and IAH (at DME 88) and LFK to get VELCO.

The MEA of 12000, I'm thinking, is to give you enough altitude to pick up IAH at 88nm. The MOCA is the safe altitude though, and 91.177(a)(1) lets you fly it if you have GPS:

(a) Operation of aircraft at minimum altitudes. Except when necessary for takeoff or landing, no person may operate an aircraft under IFR below--
(1) The applicable minimum altitudes prescribed in parts 95 and 97 of this chapter. However, if both a MEA and a MOCA are prescribed for a particular route or route segment, a person may operate an aircraft below the MEA down to, but not below, the MOCA, provided the applicable navigation signals are available. For aircraft using VOR for navigation, this applies only when the aircraft is within 22 nautical miles of that VOR (based on the reasonable
estimate by the pilot operating the aircraft of that distance); or
Click to expand...
 
djm181 said:
This is an RNAV SID but you can do it using any RNAV 1 equipment, which doesn't necessarily mean GPS. If you have DME/DME/IRU RNAV then you will be picking up IAH and DAS vortacs to identify MUSIQ, and IAH (at DME 88) and LFK to get VELCO.

The MEA of 12000, I'm thinking, is to give you enough altitude to pick up IAH at 88nm. The MOCA is the safe altitude though, and 91.177(a)(1) lets you fly it if you have GPS:
Click to expand...

I don't see an MEA above 5000 anywhere close to within a couple hundred miles of there. I'm not getting Navaid reception/protection being what those high altitudes are for. But I don't understand all the details of DME/DME/IRU either. I just thought it electronically "moved" VOR's. Those altitudes still look ATC imposed to me. If so it seems they should just underline them like on approach charts and not call them MEA's. Adding the MOCA's I see as a great idea. Where are the TERPS guys?
 
luvflyin said:
Where are the TERPS guys?
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It really isn't a TERPs issue. It is an ATC issue. The Top Altitude concept was born from confusion on some Denver SIDS that called for a climb to FL230, but had several "at or below" altitudes along the way. In those SIDS, the "top altitude" was just that - the highest altitude an airplane would be climbing to while navigating the SID.
The example you provide is a poster child for the term "top altitude" being a misnomer, as it is hardly the highest altitude to be flown while on the SID.

Once again, the FAA takes a viable concept and dorks up the implementation.
Of course this is just an internet opinion..........
 
djm181 said:
I am trying to understand the altitudes on the LURIC2 departure from KSGR.

https://skyvector.com/files/tpp/1509/pdf/05537LURIC.PDF

What is the meaning of the "Top Altitude: 4000" annotation at the top of the plate?

I assume the large difference between MOCAs and MEAs along the route is to provide clearance over the arriving traffic, so I'm unclear what Top Altitude means, and can't find any reference to it in the AIM other than in 5-2-8 regarding Climb via.

Can anyone explain this?
Click to expand...

Problem and proposed solution, note the meeting dates are twice per year:

But... nothing happened. So, they picked it up again:

Here's the memo with current guidance:

dtuuri
 
luvflyin said:
MEA's and MOCA's on SID's wasn't passing the logic test with me. That is what they are calling it on the Legend for DP charts. The asterisks are the MOCA's. The other altitudes are MEA's which at one time guaranteed obstruction and navaid reception on an airway. These altitudes, ranging from 3100 up to 12,000 in the flatlands obviously have nothing to do with that. TERPS guys??? what's up with MEA's on on SID's???
Click to expand...
The same is true for STARs.

They are not really MEAs, at least not in the sense of being the minimum altitude assuring obstruction clearance and acceptable navigational signal coverage. If you look at such things as TERPS, you'll see, for example that MEAs are
==============================
based upon obstacle clearance over the terrain or over manmade objects, adequacy of navigation facility performance, and communications requirements
==============================
The emphasis is mine. "Based upon" doesn't necessarily mean exclusivity so, in theory, there could be other factors that lead to the establishment of a route MEA.

There are plenty of examples of SID and STAR MEAs that have no relation to the "real" MEA of the routs segments. I think of them as default minimum altitudes in the absence of ATC instructions. And ATC instructions is essentially what a SID or STAR is, so there's really no discrepancy between a top altitude in a SID (in this example, part of the initial climb sequence) and a substantially higher charted MEA.

If that explanation sounds a bit convoluted, it is. The takeway is much simpler:

They are not really MEAs, at least not in the sense of being the minimum altitude assuring obstruction clearance and acceptable navigational signal coverage. They are default minimum procedural altitudes subject to modification by ATC instruction that probably have most of their function associated with lost comm procedures.
 
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midlifeflyer said:
The same is true for STARs.

They are not really MEAs, at least not in the sense of being the minimum altitude assuring obstruction clearance and acceptable navigational signal coverage. If you look at such things as TERPS, you'll see, for example that MEAs are
==============================
based upon obstacle clearance over the terrain or over manmade objects, adequacy of navigation facility performance, and communications requirements
==============================
The emphasis is mine. "Based upon" doesn't necessarily mean exclusivity so, in theory, there could be other factors that lead to the establishment of a route MEA.

There are plenty of examples of SID and STAR MEAs that have no relation to the "real" MEA of the routs segments. I think of them as default minimum altitudes in the absence of ATC instructions. And ATC instructions is essentially what a SID or STAR is, so there's really no discrepancy between a top altitude in a SID (in this example, part of the initial climb sequence) and a substantially higher charted MEA.

If that explanation sounds a bit convoluted, it is. The takeway is much simpler:

They are not really MEAs, at least not in the sense of being the minimum altitude assuring obstruction clearance and acceptable navigational signal coverage. They are default minimum procedural altitudes subject to modification by ATC instruction that probably have most of their function associated with lost comm procedures.
Click to expand...

Its a government agency. Why shouldn't words have two different meanings and applications? It's only tied to safety of flight and consistent navigation instructions...
 
Clark1961 said:
Its a government agency. Why shouldn't words have two different meanings and applications? It's only tied to safety of flight and consistent navigation instructions...
Click to expand...
It would definitely be helpful for understanding if a different term were used but operationally - safety of flight and consistent navigation instructions - I'm not sure there's really that much difference in terms of what we actually do with them as pilots. Can you think of a situation in which it does?

My WAG is that the FAA decided yet another acronym wasn't really needed.
 
midlifeflyer said:
It would definitely be helpful for understanding if a different term were used but operationally - safety of flight and consistent navigation instructions - I'm not sure there's really that much difference in terms of what we actually do with them as pilots. Can you think of a situation in which it does? .
Click to expand...

What I'm thinking is IFR enroute where MEA is meaningful for obstacle clearance vs MEA on the departure isn't tied to obstacle clearance and ATC routinely gives a lower altitude. The pilots in the area learn that MEA isn't a hard number.

Okay, we already know that MEA isn't necessarily a hard number in some situations but those are usually include a vector and we aren't necessarily on an airway.
 
midlifeflyer said:
It would definitely be helpful for understanding if a different term were used but operationally - safety of flight and consistent navigation instructions - I'm not sure there's really that much difference in terms of what we actually do with them as pilots. Can you think of a situation in which it does?

My WAG is that the FAA decided yet another acronym wasn't really needed.
Click to expand...

There is only one MEA definition used. In many cases of SIDs and STARs it is misused. I opened an issue on the topic at the ACF a couple of meetings back. The resolution is an update to the relevant orders with guidance for not using an MEA solely for ATC. MEA is permitted, but its usage is to have the standard meaning. Otherwise altitudes with minimum or maximum or absolute should be used. The newest versions of the orders are not yet in effect.
 
John Collins said:
There is only one MEA definition used. In many cases of SIDs and STARs it is misused. I opened an issue on the topic at the ACF a couple of meetings back. The resolution is an update to the relevant orders with guidance for not using an MEA solely for ATC. MEA is permitted, but its usage is to have the standard meaning. Otherwise altitudes with minimum or maximum or absolute should be used. The newest versions of the orders are not yet in effect.
Click to expand...

I'm glad to see it's going in that direction. A problem with "interpreting" a FAR to make it "covenient" to the use you want at the time is it undermines the credibility of FAR's. If "you guys" are going to say thats not what it really means when it's convenient for you then where's it going to stop? What exactly is ACF? Do you really just meet twice a year and if no solution is found just put it off for another six months? Is ACF the final Authority or do you send your recommendations up to a final Authority? Sometimes it seems to me that there is no one actually in charge anymore.
 
luvflyin said:
I'm glad to see it's going in that direction. A problem with "interpreting" a FAR to make it "covenient" to the use you want at the time is it undermines the credibility of FAR's. If "you guys" are going to say thats not what it really means when it's convenient for you then where's it going to stop? What exactly is ACF? Do you really just meet twice a year and if no solution is found just put it off for another six months? Is ACF the final Authority or do you send your recommendations up to a final Authority? Sometimes it seems to me that there is no one actually in charge anymore.
Click to expand...

The ACF is the Aeronautical Charting Forum. It is a public meeting held twice a year in the DC area. Hosted by the FAA, it includes members from industry and FAA charting. It is an outreach from the FAA to help identify and correct charting issues with the flying community. You can see the minutes of the various meetings here at http://www.faa.gov/air_traffic/flight_info/aeronav/acf/

This is a two day meeting, but there is a also a more focused group that meets at the same location for one day before the ACF, it is the ACF-IPG, or Instrument Procedures Group http://www.faa.gov/about/office_org/headquarters_offices/avs/offices/afs/afs400/afs420/acfipg/
 
John Collins said:
The ACF is the Aeronautical Charting Forum. It is a public meeting held twice a year in the DC area. Hosted by the FAA, it includes members from industry and FAA charting. It is an outreach from the FAA to help identify and correct charting issues with the flying community. You can see the minutes of the various meetings here at http://www.faa.gov/air_traffic/flight_info/aeronav/acf/

This is a two day meeting, but there is a also a more focused group that meets at the same location for one day before the ACF, it is the ACF-IPG, or Instrument Procedures Group http://www.faa.gov/about/office_org/headquarters_offices/avs/offices/afs/afs400/afs420/acfipg/
Click to expand...

The ACF-IFP came about as the result of an ALPA petition to the FAA in circa 1991. It took a bit of time, but finally the then-Administrator signed off on it. The charting portion came about when the managers decided charting should be split off from the procedurally oriented ACF.

The ACF isn't quite at the level of a formal Advisory Committee. But, it is at the level that each meeting notice must be published in the federal register.
 
John Collins said:
The ACF is the Aeronautical Charting Forum. It is a public meeting held twice a year in the DC area. Hosted by the FAA, it includes members from industry and FAA charting. It is an outreach from the FAA to help identify and correct charting issues with the flying community. You can see the minutes of the various meetings here at http://www.faa.gov/air_traffic/flight_info/aeronav/acf/

This is a two day meeting, but there is a also a more focused group that meets at the same location for one day before the ACF, it is the ACF-IPG, or Instrument Procedures Group http://www.faa.gov/about/office_org/headquarters_offices/avs/offices/afs/afs400/afs420/acfipg/
Click to expand...

Thanks for the info. How public is it? Could I just show up and listen? Participate?
 
luvflyin said:
Thanks for the info. How public is it? Could I just show up and listen? Participate?
Click to expand...

The federal register notice gives those particulars. If you jump through the modest hoops then, yes, you can show up and be involved in the discussion if you choose. But, if you want to originate an issue then you have to subject a written issue paper in the prescribed format, which also has a cutoff date.
 
aterpster said:
The ACF-IFP came about as the result of an ALPA petition to the FAA in circa 1991. It took a bit of time, but finally the then-Administrator signed off on it. The charting portion came about when the managers decided charting should be split off from the procedurally oriented ACF.
Click to expand...

......charting should be split off from the procedurally oriented ACF.....

No wonder we're all going nuts in here trying to figure out what the heck is up with this chart or that chart. It's like after the engineers build the engine they just tell the marketing department to write a service manual. Actually I can see a value having the forums separate and send their recommendations on up. But someone seems to not be putting the pieces together very well. The so called finished product keeps getting kicked back down.
 
luvflyin said:
......charting should be split off from the procedurally oriented ACF.....

No wonder we're all going nuts in here trying to figure out what the heck is up with this chart or that chart. It's like after the engineers build the engine they just tell the marketing department to write a service manual. Actually I can see a value having the forums separate and send their recommendations on up. But someone seems to not be putting the pieces together very well. The so called finished product keeps getting kicked back down.
Click to expand...

The meetings are largely attended by the same folk at the same location. It is really a three day meeting with a procedures focus and then just charting issues. Many issues have both components.
 
Clark1961 said:
What I'm thinking is IFR enroute where MEA is meaningful for obstacle clearance vs MEA on the departure isn't tied to obstacle clearance and ATC routinely gives a lower altitude. The pilots in the area learn that MEA isn't a hard number.
Click to expand...
Based on what I've seen, the MEA on many SIDs and STARs are substantially higher that the en route MEA, not lower. That's true for the subject departure too. The top altitude is lower, but that's not an MEA issue any more than is a controller giving altitudes based on MVA.
 
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