"Descend Via"

Bradley Grafelman

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"Descend Via"
« Reply #15 on: November 07, 2013, 11:19:45 AM »
Quote from: Adam Smith
I've interpreted it as you can only issue the "descend via" instructions if the STAR has hard altitudes, (line above and below) otherwise you descend them manually.
Quote from: Ryan Geckler
Yup. See the FRDMM2 arrival into DCA. That's a "descend via" arrival.

I'm going to strongly disagree with both of you on that point. Why must the altitude restriction be a hard restriction? Nothing in any FAA document states that, and that's certainly not the case with real-world controllers.

First example that comes to my mind would be the RIIVR2 into KLAX. You're saying you won't hear "Descend via the RIIVR Two arrival" on LiveATC (or in ZLA on VATSIM ) countless times every day simply because the RIIVR intersection doesn't have a hard altitude?

EDIT: And just in case you try to get sneaky and claim that RIIVR is still a "boxed" altitude limit, I'll still argue that "Descend via the BASET3 arrival" is perfectly fine as well despite the altitude restrictions at REEDR, DOWNE, etc.

EDIT2: After actually looking at the FRDMM2 arrival, I apparently misunderstand Ryan and/or both of you. My point was simply that a STAR could have zero "hard" altitudes and contain nothing but "at or above" altitudes and you'd still be able to use "descend via" with it. (Now, if the pilot acknowledges the instruction and never leaves his altitude, that's perfectly valid... he just probably won't get to land any time soon.)
« Last Edit: November 07, 2013, 11:25:02 AM by Brad Grafelman »

Ryan Geckler

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"Descend Via"
« Reply #16 on: November 07, 2013, 11:59:44 AM »
Quote from: Brad Grafelman
I'm going to strongly disagree with both of you on that point. Why must the altitude restriction be a hard restriction? Nothing in any FAA document states that, and that's certainly not the case with real-world controllers.

First example that comes to my mind would be the RIIVR2 into KLAX. You're saying you won't hear "Descend via the RIIVR Two arrival" on LiveATC (or in ZLA on VATSIM ) countless times every day simply because the RIIVR intersection doesn't have a hard altitude?

The reason it works for the RIIVR is that RIIVR is an IAF on approach plates. If you weren't clearing someone for the approach, you'd have to specify an altitude to descend to VIA the arrival... ala "Descend via the RIIVR2 arrival, maintain 10000."

[!--quoteo--][div class=\\\'quotetop\\\']QUOTE [/div][div class=\\\'quotemain\\\'][!--quotec--]EDIT: And just in case you try to get sneaky and claim that RIIVR is still a "boxed" altitude limit, I'll still argue that "Descend via the BASET3 arrival" is perfectly fine as well despite the altitude restrictions at REEDR, DOWNE, etc.[/quote]

You can still descend via it, but again, you need to specify an altitude to maintain simply because the last published altitude is an at or above... "descend via the BASET3 arrival, maintain 8000."

[!--quoteo--][div class=\\\'quotetop\\\']QUOTE [/div][div class=\\\'quotemain\\\'][!--quotec--]EDIT2: After actually looking at the FRDMM2 arrival, I apparently misunderstand Ryan and/or both of you. My point was simply that a STAR could have zero "hard" altitudes and contain nothing but "at or above" altitudes and you'd still be able to use "descend via" with it. (Now, if the pilot acknowledges the instruction and never leaves his altitude, that's perfectly valid... he just probably won't get to land any time soon.)[/quote]

Yup.
Ryan Geckler - GK
VATUSA9 | Traffic Management Unit Director
Former VATUSA3 | Division Training Director
Minneapolis ARTCC | RW Miami ARTCC

William Lewis

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"Descend Via"
« Reply #17 on: November 07, 2013, 12:10:06 PM »
I think it all just depends on your location and how the airspace is designed. Some airspace have profiled decent arrivals designed only for center, others have profiled decent arrival designed only for TRACON, some designed for both, some none at all.
Former ZTL Air Traffic Manager
Former ZID Training Admin

Kris Kendrick

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"Descend Via"
« Reply #18 on: November 07, 2013, 06:19:26 PM »
At Memphis, CTR issues the "descend via" clearance, unless TRACON is online  and specifically request for us to not do it, due to traffic, etc. We look at it as a default "green light" LOA, similar to DEL issuing departure clearances for all departure gates... unless TRACON specifically closes a gate.

I think the important thing to understand is that the LOA's are set up in the RW to maximize flow and efficiency. I am a firm believer that our LOA's do not necessarily have to be a carbon copy of the RW, as long as it works for us in the environment that we are working in. The "descend via" from En Route has been a huge time saver and made for a much more efficient TRACON environment. We just pop in "ARN" for 'descending via the arrival landing north', for example, in the scratch pad and that is pretty much it until it is time to turn the aircraft onto the approach.

Obviously not every airspace is setup for this, but for those that are, it is a very effective tool to use.

[img]http://i251.photobucket.com/albums/gg302/skiclash77/KrisSig1-2.png\" border=\"0\" class=\"linked-sig-image\" /]

KRIS R. KENDRICK

Tim Farrell

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"Descend Via"
« Reply #19 on: November 08, 2013, 11:57:34 AM »
This statement pretty much sums it up. It can be found in the 7110.65 4-7-1 Altitude Information -

A descend via clearance must not be used where procedures contain published “expect” altitude restrictions.
Tim Farrell, FDC1601
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Brad Littlejohn

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"Descend Via"
« Reply #20 on: November 08, 2013, 12:36:43 PM »
Quote from: Tim Farrell
This statement pretty much sums it up. It can be found in the 7110.65 4-7-1 Altitude Information -

A descend via clearance must not be used where procedures contain published “expect” altitude restrictions.

Be all/End all here. If the arrival doesn't call for it, they shouldn't do it, and should be up to the TAs of those sectors to make that clear, or get a bit of retraining done for when to use that for their STARs.

BL.

Wesley Miles

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"Descend Via"
« Reply #21 on: November 08, 2013, 04:04:08 PM »
Thanks everyone for your input... I think that was a good discussion!  I agree Brad/Tim... this topic is pretty much closed with that.
Wes Miles
Division General Manager
VATUSA

Harold Rutila

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"Descend Via"
« Reply #22 on: November 18, 2013, 09:20:55 PM »
Quote from: Tim Farrell
This statement pretty much sums it up. It can be found in the 7110.65 4-7-1 Altitude Information -

A descend via clearance must not be used where procedures contain published “expect” altitude restrictions.
This is the proper response to the question on DEN's procedures. The POWDR, LANDR, LARKS, QUAIL, SAYGE, TOMSN, RAMMS, and DANDD arrivals all have "Expect clearance to cross" information printed on the chart. We issue "Cross [fix] at and maintain [altitude]." Our new RNAV arrivals have crossing altitudes that make the use of "Descend via" appropriate.

[!--quoteo(post=0:date=:name=Kris Kendrick)--][div class=\\\'quotetop\\\']QUOTE (Kris Kendrick)[/div][div class=\\\'quotemain\\\'][!--quotec--]I think the important thing to understand is that the LOA's are set up in the RW to maximize flow and efficiency. I am a firm believer that our LOA's do not necessarily have to be a carbon copy of the RW, as long as it works for us in the environment that we are working in.[/quote]
The only thing that would be in an LOA would be crossing altitudes in the case of STARs with "Expect to cross [fix]" information. The use of "Descend via" would be contained in a facility SOP or addressed to controllers in training. I get your point, however.