Descend Via

[aggiepilot04]

Howdy all.  Yesterday, I returned from Chicago to Austin after a good weekend with unbeatable patio weather.  Good flight for the most part, but some procedural questions came up on the arrival.  Somewhere over east Texas, I was assigned Descend via the Sewzy Three arrival landing north, direct to SSOLO.  I am based at AUS, so being assigned an arrival or departure is par for the course, but I believe this is the first time that I've been given a "descend via" clearance (and it was definitely the first time that I've been given the Sewzy Three).  I admittedly have limited experience in the flight levels, so maybe that's the reason.  I flew the arrival without any problems (G1000 VNAV capabilities made this easy), but I wasn't as confident in the procedures as I should have been.  Definitely something I'll bring up during my next IPC, but I figured I would start here.

Here is the Sewzy Three: http://155.178.201.160/d-tpp/1708/00556SEWZY.PDF

And here are my questions:

1. There's a NOTE for turbojet or turboprop aircraft only.  Should I have rejected this arrival based on this note alone?  If so, shouldn't ATC have known not to assign it to me in the first place?
2. I was flying at 18 and elected to cross SSOLO at 17 to make the next step down easier.  Should I have instead crossed SSOLO at 18 before starting down?  Other than the "descend via", I was not assigned any altitude restrictions or changes.
3. Text of the arrival says to expect RNAV (RNP) approach -OR- vectors to final.  Since clearly I'm not RNP authorized, I assume that I'm expecting vectors for the RNAV GPS or the visual unless otherwise instructed.  Is that correct, or could I be surprised with the ILS?
4. I was on an ICAO IFR flight plan.  Is it possible that I have something messed up there that would lead to having this arrival assigned in the first place?
5. Am I the only one that has never received a "descend via" clearance (until now)??

By the way, 5 sloppy joes for $5 at the bar/restaurant on the field at KIGQ.  We arrived after the kitchen had closed, and that's all that they could make.  I wasn't mad about it though...that is the cheapest that I've ever fed a family of 4!

Thanks in advance.

[smccray]

2 minutes ago, aggiepilot04 said:

Am I the only one that has never received a "descend via" clearance (until now)??

 

I receive an arrival every trip back into the DFW area and I've never received a descend via clearance.  I suspect that my normal cruising altitude from 8-10K MSL contributes to the lack of descend via instructions.  I do generally receive a crossing restriction of 7000 ft at the primary fix on the arrival.

[AaronDC8402]

I know that an altitude with the line under it indicates that is a minimum altitude. Are those minimum speeds for each leg as well? I'm not sure I could hit those numbers in a nose dive after the wings fell off. That would have been reason enough for me to either reject the clearance or at least ask about it.

 

[AaronDC8402]

Oh, and thanks for asking this question. I really like threads like this. Since I RARELY ever hear a departure or arrival clearance, I like reading about it in an effort to stay as current as possible with them.

[Bolter]

As it says turbojet and turboprop only, it certainly seems it was not appropriate to assign as published, regardless.  Not that I would have realized it at the moment it was assigned to me, as I would not be familiar with the STAR, and probably scrambling through the plate trying to get ahead of the plane again.   

Not getting a new altitude assigned suggests you were to follow the arrival as published, as that is where your altitude assignment would be.  Until you were at SSOLO, you were not on the arrival, so I think you should not descend until then, unless given other instructions like a new altitude then to continue with the Arrival.    

Just my thoughts as an IFR PP who is sitting at my desk, thinking about flying. -dan

 

[smccray]

11 minutes ago, AaronDC8402 said:

I know that an altitude with the line under it indicates that is a minimum altitude. Are those minimum speeds for each leg as well? I'm not sure I could hit those numbers in a nose dive after the wings fell off. That would have been reason enough for me to either reject the clearance or at least ask about it.

 

ooo- good question- I missed that- those are exact indicated airspeeds not min or max (line above and below the value).  I know the Acclaim is fast, but I'm fairly certain the Acclaim can't hit those airspeeds.  Not a big deal as the controller can delete the speeds, but certainly something to look for if assigned the arrival.  Nice catch!

 

13 minutes ago, Dan at FUL said:

Not getting a new altitude assigned suggests you were to follow the arrival as published, as that is where your altitude assignment would be.  Until you were at SSOLO, you were not on the arrival, so I think you should not descend until then, unless given other instructions like a new altitude then to continue with the Arrival.    

 

I may be wrong, but I believe that if a controller clears you to descend via the STAR, and the first fix has a altitude from 170, you're immediately cleared to descend to the 170- I know that's how I would have flown it.  Doesn't make it right though- hoping someone will come along and confirm which interpretation is correct.

[Bolter]

Just now, smccray said:

I may be wrong, but I believe that if a controller clears you to descend via the STAR, and the first fix has a altitude from 170, you're immediately cleared to descend to the 170- I know that's how I would have flown it.  Doesn't make it right though- hoping someone will come along and confirm which interpretation is correct.

I interpreted it like an Approach.  You do not descend until your established or given a specific instruction.  If there was an obstacle/traffic/airspace/airway/other between you and the SSOLO fix, you may clear at 18 and not 17.  I have assumed that direct SSOLO means you are not already on the STAR, but somewhere unknown.   

[smccray]

1 minute ago, Dan at FUL said:

I interpreted it like an Approach.  You do not descend until your established or given a specific instruction.  If there was an obstacle/traffic/airspace/airway/other between you and the SSOLO fix, you may clear at 18 and not 17.  I have assumed that direct SSOLO means you are not already on the STAR, but somewhere unknown.   

That makes sense- and I may have it wrong.  I was actually thinking about it like "pilots discretion" to SSOLO.  From the moment you receive the PD clearance  (or the descend via instruction) you own the airspace from your current location and below down to the discretion altitude.  Crossing SSOLO, you continue your descent below 170 remaining above 13,000 at MSTLO, above 8000 at VADRR, and at 4000 by JEDYE.

[aggiepilot04]

52 minutes ago, smccray said:

That makes sense- and I may have it wrong.  I was actually thinking about it like "pilots discretion" to SSOLO.  From the moment you receive the PD clearance  (or the descend via instruction) you own the airspace from your current location and below down to the discretion altitude.  Crossing SSOLO, you continue your descent below 170 remaining above 13,000 at MSTLO, above 8000 at VADRR, and at 4000 by JEDYE.

That's how I interpreted it as well, but I wasn't certain.  I probably should have asked to confirm, but I don't think there's a notion of "being established" on the arrival like there is an approach.  Since he gave me 'descend via' and direct SSOLO, I was considered "on" the arrival.

As far as speeds go, I (incorrectly) thought that these were max speeds which wouldn't have been a factor.  I missed the fact that there was a line on bottom and top.  Vne on the Acclaim is 196 KIAS.  The controller didn't mention my speed deficiencies though.  The only time that I heard from them on the arrival was after SSOLO giving me the altimeter setting (he wasn't sure whether or not he gave it to me after leaving 180) and then pointing out the 737 that I was following after SMRFF.

Edited July 31, 2017 by aggiepilot04

[Danb]

The controller obviously thought you were a turboprop, maybe filling out your ICAO it was depicted incorrectly.

[kortopates]

See AIM 5-4-1 a.2.(a).(2) - "When cleared to a waypoint depicted on a STAR, to descend from a previously assigned altitude at pilots discretion to the altitude depicted at that waypoint."

Which was 17K to FL230.

But you should have told ATC you would be unable to comply with the speed restrictions. I am sure he knows what a M20T and Mooney are and I doubt he really cared about your speed, but technically they aren't suppose to give these to us, and therefore we don't expect to get them either. 

 

 

[Davarron]

4 hours ago, aggiepilot04 said:

Howdy all.  Yesterday, I returned from Chicago to Austin after a good weekend with unbeatable patio weather.  Good flight for the most part, but some procedural questions came up on the arrival.  Somewhere over east Texas, I was assigned Descend via the Sewzy Three arrival landing north, direct to SSOLO.  I am based at AUS, so being assigned an arrival or departure is par for the course, but I believe this is the first time that I've been given a "descend via" clearance (and it was definitely the first time that I've been given the Sewzy Three).  I admittedly have limited experience in the flight levels, so maybe that's the reason.  I flew the arrival without any problems (G1000 VNAV capabilities made this easy), but I wasn't as confident in the procedures as I should have been.  Definitely something I'll bring up during my next IPC, but I figured I would start here.

Here is the Sewzy Three: http://155.178.201.160/d-tpp/1708/00556SEWZY.PDF

And here are my questions:

1. There's a NOTE for turbojet or turboprop aircraft only.  Should I have rejected this arrival based on this note alone?  If so, shouldn't ATC have known not to assign it to me in the first place?
2. I was flying at 18 and elected to cross SSOLO at 17 to make the next step down easier.  Should I have instead crossed SSOLO at 18 before starting down?  Other than the "descend via", I was not assigned any altitude restrictions or changes.
3. Text of the arrival says to expect RNAV (RNP) approach -OR- vectors to final.  Since clearly I'm not RNP authorized, I assume that I'm expecting vectors for the RNAV GPS or the visual unless otherwise instructed.  Is that correct, or could I be surprised with the ILS?
4. I was on an ICAO IFR flight plan.  Is it possible that I have something messed up there that would lead to having this arrival assigned in the first place?
5. Am I the only one that has never received a "descend via" clearance (until now)??

By the way, 5 sloppy joes for $5 at the bar/restaurant on the field at KIGQ.  We arrived after the kitchen had closed, and that's all that they could make.  I wasn't mad about it though...that is the cheapest that I've ever fed a family of 4!

Thanks in advance.

Being an airline pilot, I fly these descend via stars all the time. In regards to your second question, crossing SSOLO at 17 is perfectly fine since you are cleared to descend to the lowest altitude, at your discretion, of the waypoint you're cleared to or of the first waypoint with an altitude restriction when given the descend via clearance. The speeds on that arrival are mandatory unless given a different speed from ATC when they give you the descend via clearance. In regards to the note about it being only for turbojet or turboprop aircraft, ATC should NOT have assigned this arrival to you. Since you were flying and obviously not expecting to receive this, I would honestly file a NASA ASRS report to cover yourself incase the FAA reviews the ATCs actions since we know he shouldn't have assigned this to you. Hope this helps out and makes sense.

[peevee]

You should not have been assigned the arrival. In fact the system shouldn't have even let them put it in your flight plan, wrong type, don't meet the performance based nav requirements....

[carusoam]

Great question, Aggie!

I'm Glad you shared it...

Flying the plane, reading through the details and getting some unexpected curve ball while cruising 200kts over the ground...

It must be an uncomfortable feeling that comes with that... Wording the question artfully may help...

Where are the N1 and N2 gauges in our planes?  

Thanks again, and thanks to the guys that are familiar with restrictions like turbine and turboprop only....

Best regards,

-a-

[carqwik]

I think the controllers really don't know a Mooney Acclaim from a King Air 90...all they see is a blip at a flight level doing more than 200 knots.  They then go into "well we always give them the arrival" so to speak and I bet that's what happened.  Of course, the only comment I'd say is that looking at the arrival, you did have some responsibility to say you can't do the speeds.  That would wake the controller up and he'd say either 1) disregard the speeds, just do your best forward speed and comply with the altitudes; or 2) oh yea, direct SSOLO, cross at XX thousand, expect vectors for the approach.

[aggiepilot04]

@carqwik, I think you're exactly right...I think they saw me doing 220 kts across the ground at FL180 and assumed that I wasn't a piston aircraft.

And thanks all for the great info.  The speed and accuracy of the knowledge here never fails to amaze me.  To recap (including a couple of PMs that I've received), here are the lessons learned:

1. Speed restrictions are not just speed limits.  Make sure you can comply after being assigned an arrival, and advise if you can't.
2. Descend via = pilots discretion from your current altitude to a compliant altitude at the first assigned fix (good list of descend via FAQs here).
3. Garmin has a spreadsheet to assist with ICAO codes here.  I was missing a couple of codes, but I did not select T1 (indicating RNAV RNP approach capable).  So other than missing a couple of capabilities, my ICAO flight plan was correct.
4. Yet another good reason to file/fly IFR in visual conditions.  If nothing else, I learned that altitudes in the G1000 flight plan in white letters indicate default but unselected altitudes.  You have to select and toggle the text to blue in order to arm a vertical track.
5. At 14.6 GPH, I was burning less gas than anyone else on the Sewzy Three arrival yesterday.

Thanks again!

[carusoam]

Does Sewzy have a close TN'd sister?

Is there a similar approach for those who are flying piston planes? 

Best regards,

-a-

 

[FlyBorne]

3 hours ago, Davarron said:

Being an airline pilot, I fly these descend via stars all the time. In regards to your second question, crossing SSOLO at 17 is perfectly fine since you are cleared to descend to the lowest altitude, at your discretion, of the waypoint you're cleared to or of the first waypoint with an altitude restriction when given the descend via clearance. The speeds on that arrival are mandatory unless given a different speed from ATC when they give you the descend via clearance. In regards to the note about it being only for turbojet or turboprop aircraft, ATC should NOT have assigned this arrival to you. Since you were flying and obviously not expecting to receive this, I would honestly file a NASA ASRS report to cover yourself incase the FAA reviews the ATCs actions since we know he shouldn't have assigned this to you. Hope this helps out and makes sense.

Hmm, I didn't know that the speeds on the arrival are mandatory. I'm really learning a lot from this thread.

[jaylw314]

Thread hijack, sorry.

Has anyone else noticed the waypoint names?

Star Wars references - WINDU, SSOLO, VADRR, JEDYE

Homage to Stevie Ray Vaughan - STVEY, RAYYE, VAWWN

I'm not sure what the connection with Smurfs and horses are, and who the heck is Sewzy?

 

 

[carusoam]

Somebody in the charting department has a sense of humor to go with their Jedi memory tricks... 

On the east coast we have late night comedians. JIMEE, FALON, WINKK. On a victor skyway going East out of CYN (Coyle VOR)

Best regards,

-a-

[peevee]

33 minutes ago, carusoam said:

Somebody in the charting department has a sense of humor to go with their Jedi memory tricks... 

On the east coast we have late night comedians.

Best regards,

-a-

Sometimes the center controllers pick them.

 

[Yooper Rocketman]

I was always told "assigned speeds" were "IAS".  I know of no turboprops capable of 280 Knots "indicated".  Even the TBM has a VNE under that (266k).  A Cessna Conquest is 247 knots.  I file 300 knots but my VNE is 274 knots indicated.  I don't see how ANY turboprops can comply with that procedure?

Tom

[jetdriven]

Maybe a Brasilia or DO-328.  Those are pretty fast. But yeah, like you said, 280 is optimistic for almost all turboprops. 

[midlifeflyer]

On 8/1/2017 at 0:51 AM, FlyBorne said:

Hmm, I didn't know that the speeds on the arrival are mandatory. I'm really learning a lot from this thread.

Just like altitudes, a line above is a maximum, a line below is a minimum, lines above and below is a mandatory.

My guess? Controller error.

[midlifeflyer]

On 7/31/2017 at 6:43 PM, kortopates said:

See AIM 5-4-1 a.2.(a).(2) - "When cleared to a waypoint depicted on a STAR, to descend from a previously assigned altitude at pilots discretion to the altitude depicted at that waypoint."

Which was 17K to FL230.

Yup, think of it as the equivalent of "cross SSOLO at..."