Accept 'Except'? (...and no Autopilot love)

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Cyrus
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Accept 'Except'? (...and no Autopilot love)

Post by Cyrus »

With regards to the Seal Beach 5 Departure...

"TAKEOFF RUNWAYS 25L/R: Climb via heading 250 to cross SMO R-154 at or below 3000’ then turn left heading 200 for vector to SLI VORTAC. Thence....
. . . . via (assigned route). All aircraft expect further clearance to filed flight level three minutes after departure."


Nothing controversial there. But, for my LAX to SNA flight, I was told "Climb via SID, except maintain 4000". This last part (the EXCEPTion) threw me off.

You can listen to the Clearance process (and my follow up questions a few seconds later) here, starting from 7:15.

I got (and still am) confused because "...except..." seems to imply that we're overriding something on the standard procedure.

I read this, but it didn't really help me. Saying "You are cleared to the altitude that ATC assigned and you must comply with all other altitude and speed restrictions unless explicitly cancelled by ATC." doesn't do anything to clear up my confusion.

Now, I will say that I think I understand what the regs are trying to convey (see here and read the notes after each instance of "except maintain"). However, to play devil's advocate, what if ATC wanted you to climb via the SID, but (for whatever opertaional reason on that day/traffic/winds) wanted you to be at 4000ft by SMOR145, instead of the published 3000ft? What would the Clearance sound like then?

My issue is coming down to the use of the word "Except". To me, this suggests a unusual/exceptional/unique situation that *overrides* something in the published SID. To me, it would be less ambiguous to use the word "THEN", i.e. "Climb via SID, THEN maintain 4000" rather than "Climb via SID, EXCEPT maintain 4000"

I hope this doesn't come across as nitpicking. I'm just really trying to understand the logic that was employed by the FAA analyst when they drafted this... all those years ago.

On a more positive note, I'm really making progress without the autopilot. I flew the above flight last night as a practice for the I-6 rating and only used the AP to hold 4000 feet once there. I just about managed to hold the localizer and the glideslope by hand, whereas before I would just have hit "APP" on the autopilot and been done with it. It is SO much more rewarding flying it by hand... all while knowing I'll need to switch to tower soon, get out the airport diagram for taxiing, GUMPS, etc., etc. I was a sweaty, nervous mess by time that I touched concrete on 20R :lol: The biggest challenge was holding my altitude during the turns, especially the Procedure Turn at SAGER.

I just wish someone had told me never to use the autopilot from the start. (Actually, I'm sure they did... I just didn't listen).
-Cyrus Kapadia. A few RW hours in a C172, then a 15 year hiatus. Joined PE in Dec'12, then took a break. Now I'm back, learning fast and loving it. If I'm on, it's usually between 22h and midnight EST with Baron 258E, Skyhawk 176CM or Learjet 66L.
Pieces
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Re: Accept 'Except'? (...and no Autopilot love)

Post by Pieces »

Edit: Keith's reply wins. I'll keep mine here for history.

I suspect the "exception" here is for the lost comm procedure. In the text "All aircraft expect further clearance to filed flight level three minutes after departure" is for a lost comm situation. If you lose comms, climb to your filed altitude after 3 minutes. I don't know what your filed altitude was (probably was 4000), but this is basically saying climb via the sid (comply with restrictions) but then continue your climb to 4000 without waiting the three minutes.
Last edited by Pieces on Tue Oct 14, 2014 11:34 am, edited 1 time in total.
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Keith Smith
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Re: Accept 'Except'? (...and no Autopilot love)

Post by Keith Smith »

If a SID contains altitude restrictions, the controller must use the CLIMB VIA phraseology. If the SID doesn't contain a 'top altitude', ie, and altitude to climb to and maintain, then the controller must use CLIMB VIA [sid] EXCEPT MAINTAIN [top altitude].

None of this has any bearing on lost comms AFAIK. There is still a lost comms provision with the 'all aircraft expect futher clearance to filed flight level three minutes after departure'.

Cyrus, your proposal of "CLIMB via SID , THEN maintain [assigned top altitude]" wouldn't work in cases where they want to stop you lower than certain climb restrictions. Take the PEBLE4 SID out of SAN, for example. You might be on a TEC route with an assigned altitude of 8k. "CLIMB via SID, THEN maintain 8000" would make no sense given there are at or above 13k restrictions on the SID (if memory serves).

Regarding hand flying of approaches, you absolutely want to practice that prior to building heavy reliance on the autopilot. This is why it's generally a mistake for people to start their IFR flying in heavy airliners, skipping pistons and turboprops.
gavink42
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Re: Accept 'Except'? (...and no Autopilot love)

Post by gavink42 »

So, the "except maintain 4000" phrase overrides the expect further clearance altitude (at the end of the sid)? Which leaves the "...at or below 3000..." still in effect?
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Keith Smith
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Re: Accept 'Except'? (...and no Autopilot love)

Post by Keith Smith »

No, "except maintain 4000" means that you climb initially to 4000 while still complying with any restrictions prior to that. It has no bearing on the lost comms. You'd still climb to final flight level within xx mins if you lose comms, per the lost comms procedures in the FARs which state that you should climb to the highest of the minimum IFR altitude, assigned altitude, or altitude to expect at a given point or time.
gavink42
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Re: Accept 'Except'? (...and no Autopilot love)

Post by gavink42 »

Gotcha... I wasn't reading your initial response correctly. Makes sense!
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Cyrus
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Re: Accept 'Except'? (...and no Autopilot love)

Post by Cyrus »

Thanks for the feedback/input, everyone.

I still feel that the wording of "Climb via SID, EXCEPT maintain 4000" [for this SID] is less than ideal for this simple reason: There is nothing EXCEPTional (or contradictory vis-à-vis the SID) about staying below 3000ft by SMOR145 and then climbing to my filed altitude of 4000ft. This seems perfectly consistent with "All aircraft expect further clearance to filed flight level three minutes after departure" ... so why suggest otherwise with the word "except".

Keith, your PEBLE4 example actually supports my argument, doesn't it? (yes, I'm doubling-down :lol:). That is, in that example, "Climb via SID, EXCEPT maintain 8000" makes perfect sense precisely because the 8000ft altitude is an EXCEPTion to the SID. Whereas, in the SLI5 case there is nothing EXCEPTional about the 4000ft top altitude (sorry for all the fugly CAPS; just trying to drive home my point)

Having said all that - and tying to see this from the other side - I am pretty sure that it's in everyone's best interests to have as few standard phrases as possible, and then each pilot simply needs to learn how to read any given plate and know how the particular ATC/Clearance phrase translates to that particular situation. What's more, I'm sure that these sort of questions are only raised by those of us learning to understand, interpret and remember Clearance phraseology. Once they are second nature, my guess is that no one questions them. (Well, I guess another possibility is that I'm flat out wrong; but that's too painful to think about on this beautiful autumnal morning)

Preemptive Edit: Keith's future reply wins. I'm just in the mood to make myself look like more of a fool than I already do. :lol:
-Cyrus Kapadia. A few RW hours in a C172, then a 15 year hiatus. Joined PE in Dec'12, then took a break. Now I'm back, learning fast and loving it. If I'm on, it's usually between 22h and midnight EST with Baron 258E, Skyhawk 176CM or Learjet 66L.
wmburns
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Re: Accept 'Except'? (...and no Autopilot love)

Post by wmburns »

If I understand your point it is for the case where the EXCEPT altitude and the flight plan altitude happen to match, then the EXCEPT isn't needed? And since (for this case) the net result is the same the controller adding EXCEPT wasn't necessary?

I'm not so sure that I totally buy into the point that using EXCEPT is "less than ideal". It should emphasize the need to not climb above 4000'. Further this would require the controller to make a special decision that this pilot and decide that EXCEPT isn't needed because the altitude filed for matches the top altitude given. All this to save two words of radio time?

One could also argue that removing a decision out of the process and using the same phraseology for everyone is "more ideal".

All kidding aside, when the "wordsmithing" is extended out as far as it can go, I'm not sure for this special case there is a technically right or wrong answer. However, it's hard to argue with majority. IE when the majority of people have a particular belief.

>>>Additional research
anal retentive: The term anal retentive (also anally retentive), commonly abbreviated to anal, is used to describe a person who pays such attention to detail that the obsession becomes an annoyance to others, potentially to the detriment of the anal-retentive person. The term derives from Freudian psychoanalysis. :P
http://en.wikipedia.org/wiki/Anal_retentiveness

minimum fuel:
http://lessonslearned.faa.gov/Avianca52/INFO_08004.pdf

:twisted:
Last edited by wmburns on Wed Oct 15, 2014 9:57 am, edited 3 times in total.
Keith Smith
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Re: Accept 'Except'? (...and no Autopilot love)

Post by Keith Smith »

When "Climb via SID" was introduced, it came with lots of documentation explaining how it is used and what it all means. It made a distinction between:
- SIDs that have altitude restrictions and top altitudes, and
- SIDs that have altitude restrictions and no top altitudes.

The distinction is made by the use of "EXCEPT MAINTAIN [initial altitude]" as part of the clearance phraseology.

I agree that it's a bit odd to say 'except' when it isn't overriding anything. I had the same reaction when it was introduced. Now that I've been using it for a while, though, as a pilot and a controller, it works.

If I am assigned a SID and I hear "maintain xxxx, expect yyyy 5 minutes after departure," then I know where are no altitude restrictions. If I hear "climb via SID" and nothing else, then I know there are restrictions as well as a published top altitude (like Vegas, for example). If I hear "climb via SID except maintain xxxx" then I know there are restrictions and no top altitude. When you approach it that way, it works. It does not have enough granularity to tell you if they're stopping you short of some of the restrictions or not (such as the PEBLE case for TEC routes), not that is it particularly important, though, since you're stopping at the top altitude anyway.

It's just a matter of training and setting expectations, like most of IFR flying. Some of the things don't mean what you might initially think (such as 'maintain xxxx, expect yyyy 5 minutes after departure', only to receive yyyy as soon as you contact departure. It's for lost comms only).
Cyrus
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Re: Accept 'Except'? (...and no Autopilot love)

Post by Cyrus »

You will all be pleased to hear that, with those last two posts (wmburns & Keith), I'm happy to let this one rest.

Your contributions and cross-examinations have been stimulating and, now, I really think we've beaten to this poor horse to death (...and then taken his carcass out back, stuck skewers into his equine eyeballs, and roasted them as if they were marshmallows).

Seriously, thanks again for the excellent (from my perspective!) discussion. Insert 25c to continue.

// Anally-Retentive-Roger, over and out //
-Cyrus Kapadia. A few RW hours in a C172, then a 15 year hiatus. Joined PE in Dec'12, then took a break. Now I'm back, learning fast and loving it. If I'm on, it's usually between 22h and midnight EST with Baron 258E, Skyhawk 176CM or Learjet 66L.
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