SID question

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Eibwen

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Eibwen
The PADRZ2.CHKNN departure at KCRQ says "...thence on (transition). Maintain 15000. Expect higher altitude 10 minutes after departure." This seems to contradict the 16000 MEAs listed for all transitions from HFMNN on out.

I understand that given lost comms then the 16000 would apply. Should I just see it as an at or above altitude that applies to all of the transitions? If you got a question about how to interpret this, how would you answer? Thanks all.
 
Looking at this further, this question seems only relevant in a lost comms situation - which removes the ambiguity. It's 63 miles to HFMNN from departure and the only way to reach that point in most aircraft would mean arriving after 10 minutes with no comms. At which point one would bump to 16000 and start evaluating where to divert to or making relevant AVEF/MEA decisions.
 
Eibwen said:
The PADRZ2.CHKNN departure at KCRQ says "...thence on (transition). Maintain 15000. Expect higher altitude 10 minutes after departure." This seems to contradict the 16000 MEAs listed for all transitions from HFMNN on out.
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The MEAs on SIDs and STARs are not MEAs in the enroute sense. If you want to look at my favorite example, look at the DRONE arrival into Norfolk, VA (KORF) and compare the MEAs in the STAR with the enroute MEAs on the same route (FL190 vs 2600’ and lower). It’s regularly assigned to light pistons at low altitudes.
 
Keep in mind that SIDS aren’t part of the e route structure, they’re designed to get you there. There’s probably a controller change between 15,000 and 16,000.
 
midlifeflyer said:
The MEAs on SIDs and STARs are not MEAs in the enroute sense. If you want to look at my favorite example, look at the DRONE arrival into Norfolk, VA (KORF) and compare the MEAs in the STAR with the enroute MEAs on the same route (FL190 vs 2600’ and lower). It’s regularly assigned to light pistons at low altitudes.
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Yeah. They aren’t MEA’s on STARS and SID’s. They are just Minimum Altitude. They are there to separate airplanes from airplanes. MEA’s separate airplanes from obstructions and ensure Navaid reception. @Eibwen , hope this helps

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Sometimes they put MOCA’s on them.
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Ah Ha, I found it. @John Collins , do you have a link to the ACF meeting where this came up?
www.pilotsofamerica.com

Top Altitude lower than MEA on SID

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...
www.pilotsofamerica.com www.pilotsofamerica.com
 
luvflyin said:
Ah Ha, I found it. @John Collins , do you have a link to the ACF meeting where this came up?
www.pilotsofamerica.com

Top Altitude lower than MEA on SID

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...
www.pilotsofamerica.com www.pilotsofamerica.com
Click to expand...

You can search through the closed or active issues at the ACF at https://www.faa.gov/air_traffic/flight_info/aeronav/acf/ or the IPG at https://www.faa.gov/about/office_org/headquarters_offices/avs/offices/afx/afs/afs400/afs420/acfipg

These meetings are now held via Zoom. They are open to the public and anyone can attend and participate or submit a recommendation.
 
luvflyin said:
Ah Ha, I found it. @John Collins , do you have a link to the ACF meeting where this came up?
www.pilotsofamerica.com

Top Altitude lower than MEA on SID

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...
www.pilotsofamerica.com www.pilotsofamerica.com
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Yep. Problem is that the SID STAR legend still identifies them as "MEA" which only has one official definition. even though they are definitely not the minimum altitude which will ensure obstacle clearance and nav signal. (The ones you circled above are mandatory altitudes for climb via clearances.)
1730044086198.png
 
The current DP order says that MEA should not be based on ATC, but only based on legitimate MEA requirements. IOW, MEA means what it means and can't be redefined by ATC.

From 8260.46J 2-1-1(d.)(2): Departure Procedure (DP) Guidelines, d. constraints. The following charting constraints apply, (2)Charting altitudes. Document altitudes for charting as follows:

(d)When ATC requests an altitude restriction for a fix located on a transition route, it must be at or above the specified minimum en route altitude (MEA) for the route (see note in paragraph 2-1-1.e(2)(b)). Do not raise an MEA to support ATC operational requirements; use fix crossing altitudes where operationally needed.
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This guidance applies to new procedures and was not complied with on many existing DP and does not always get updated when DP are up numbered, even though it should be.
 
midlifeflyer said:
Yep. Problem is that the SID STAR legend still identifies them as "MEA" which only has one official definition. even though they are definitely not the minimum altitude which will ensure obstacle clearance and nav signal. (The ones you circled above are mandatory altitudes for climb via clearances.)
View attachment 134633
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Ok, found that in the Digital Terminal Procedures Supplemental. What I posted above was from the Aeronautical Chart Users Guide. Maybe someday the left hand and the right hand at the FAA will get together and make up their mind.
 
John Collins said:
The current DP order says that MEA should not be based on ATC, but only based on legitimate MEA requirements. IOW, MEA means what it means and can't be redefined by ATC.

From 8260.46J 2-1-1(d.)(2): Departure Procedure (DP) Guidelines, d. constraints. The following charting constraints apply, (2)Charting altitudes. Document altitudes for charting as follows:



This guidance applies to new procedures and was not complied with on many existing DP and does not always get updated when DP are up numbered, even though it should be.
Click to expand...
It will take a while for procedures like the DRONE STAR to get updated to drop over 17,000 feet :D (STAR superimposed over enroute chart).

The thing though is, ATC regularly clears light pistons onto this STAR at low altitudes (I probably was assigned it at 3000 or 5000), it hardly seems the FL190 is "based on ATC" (although that might have been some time in the distant past).


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Right on, thanks for the additional discussion. These kinds of ambiguity are all over the place and it's easy to rabbit hole a little bit on each of them.
 
hahaha! Yeah aviation is nothing but rabbit holes. With the odd stick of dynamite tossed in just to keep things spicy...
 
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