Change in ILS visibility minimums

Everskyward

Everskyward

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Everskyward
For all the TERPS experts and others out there. Why do you think the visibility minimums on this approach were raised from 1/2 mile to 3/4 mile? It's been 1/2 mile for as long as I can remember. The only real difference seems to be a slight change in the missed approach. I know they have added a couple other fixes out on the final approach course but that shouldn't make a difference. Also, speaking of the missed approach, what happened to the curved arrow showing the start of the missed approach on the new approach plate? I'll admit that I normally use Jepp plates, not NACO, but it's curious that the arrow is on the old plate but not the new one. I think it's a nice feature. Did they just forget to include it?

New ILS 35R APA

Old ILS 35R APA
 
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You've got a new obstruction at 5950 ft just to the right of the approach course on short final. Just a guess.
 
Looks like they gave you a step down on the LOC for the other new obstruction on final as well. VDP now as well. :wink2:
 
Velocity173 said:
Looks like they gave you a step down on the LOC for the other new obstruction on final as well. VDP now as well. :wink2:
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I don't think the stepdown or the VDP would have changed the ILS visibility minimums. The new close-in obstacle might have been a factor but it's only 65 feet higher than the runway. I wonder what it is and why it was allowed to be built.
 
Everskyward said:
I don't think the stepdown or the VDP would have changed the ILS visibility minimums. The new close-in obstacle might have been a factor but it's only 65 feet higher than the runway. I wonder what it is and why it was allowed to be built.
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Nah I'm not saying they changed the vis because of a stepdown or VDP. Just saying the stepdown probably occured because of the new 6,403 ft obstacle on final. I think the vis changed because of the new close in obstacle though. With more and more contruction and towers encroaching on approach paths we keep getting pushed up higher and higher.

arterpster or John Collins should be on shortly to give you a definitive answer. My background was designing emergency helicopter GPS approaches.
 
This hangar is fairly new and seems to correspond to the location of the new obstacle. That would be a little ironic. There are also the buildings in the Meridian business park further southeast but I think those have been there for a while.

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Velocity173 said:
Nah I'm not saying they changed the vis because of a stepdown or VDP. Just saying the stepdown probably occured because of the new 6,403 ft obstacle on final. I think the vis changed because of the new close in obstacle though. With more and more contruction and towers encroaching on approach paths we keep getting pushed up higher and higher.

arterpster or John Collins should be on shortly to give you a definitive answer. My background was designing emergency helicopter GPS approaches.
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What I say is that folks who have a vital interest in a particular airport should be downloading and saving all the TERPs paperwork when the IAPs are in coordination.

The FAA makes is so easy now, you can even register and sign up for alerts on airports of interest.
 
aterpster said:
What I say is that folks who have a vital interest in a particular airport should be downloading and saving all the TERPs paperwork when the IAPs are in coordination.

The FAA makes is so easy now, you can even register and sign up for alerts on airports of interest.
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What good would that do other than knowing what was going to happen in advance? I thought minimum altitudes, visibilities, etc. were based on obstacles using certain parameters for clearance which cannot really be changed.

I went to the site and was able to find this document for the approach, some of which I understand and some which is just Greek to me.

http://aeronav.faa.gov/acifp/ndbr/2...A-NDBR/02A_CO_DENVER_CENTENNIAL_IL35R_APA.pdf
 
Everskyward said:
What good would that do other than knowing what was going to happen in advance? I thought minimum altitudes, visibilities, etc. were based on obstacles using certain parameters for clearance which cannot really be changed.

I went to the site and was able to find this document for the approach, some of which I understand and some which is just Greek to me.

http://aeronav.faa.gov/acifp/ndbr/2...A-NDBR/02A_CO_DENVER_CENTENNIAL_IL35R_APA.pdf
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When the procedure was in coordination one of the forms listed all the reasonf for changes.
 
aterpster said:
When the procedure was in coordination one of the forms listed all the reasonf for changes.
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Oh OK. I'm interested in what the reason for the change was for curiosity's sake but I (and others) would be more interested in having it put back the way it was. :)
 
Everskyward said:
This hangar is fairly new and seems to correspond to the location of the new obstacle. That would be a little ironic. There are also the buildings in the Meridian business park further southeast but I think those have been there for a while.

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That's Liberty Media's hangar for their jets, the building across the road is their Corporate HQ.

I want to know why they removed the transition route from FQF and how a /A aircraft is supposed to navigate to CASSE.
 
denverpilot said:
I want to know why they removed the transition route from FQF and how a /A aircraft is supposed to navigate to CASSE.
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Using the ADFs that people are removing from their airplanes? :idea:

Actually, if you look at an arrival, QUAIL SEVEN for example, it says to expect radar vectors at or before FQF.

http://aeronav.faa.gov/d-tpp/1212/09077QUAIL.PDF

I want to know what happened to the missed approach dashed arrow. It almost looks like it got cut off in the printing since I think I can see the arrowhead.
 
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Everskyward said:
Using the ADFs that people are removing from their airplanes? :idea:

Actually, if you look at an arrival, QUAIL SEVEN for example, it says to expect radar vectors at or before FQF.

http://aeronav.faa.gov/d-tpp/1212/09077QUAIL.PDF

I want to know what happened to the missed approach dashed arrow. It almost looks like it got cut off in the printing since I think I can see the arrowhead.
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Yes but the plate says "DME or RADAR Required". It also isn't required to file the arrival.

But you can't navigate to the ILS with only a DME with no transition route. So the plate must be changed to only "RADAR Required" (like KBJC), or the transition route has to be put back so theres a /A navaid transition to the ILS.

I think you're right about the missed... It's laid right on top of the Localizer now and poorly depicted.

I'd love to see the Jepp version.
 
denverpilot said:
Yes but the plate says "DME or RADAR Required". It also isn't required to file the arrival.

But you can't navigate to the ILS with only a DME with no transition route. So the plate must be changed to only "RADAR Required" (like KBJC), or the transition route has to be put back so theres a /A navaid transition to the ILS.
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Or it could say ADF or RADAR required since you can navigate to CASSE using an ADF.
 
Everskyward said:
Or it could say ADF or RADAR required since you can navigate to CASSE using an ADF.
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Correct, but it looked to me like they're getting ready to pull the beacon, or they wouldn't have switched it to "DME or RADAR".

NexGen you know. :)
 
Got an answer pretty quick.

Hello Mari,
The visibility was raised to 3/4 mile because of penetrations to the 20:1 visual portion of final surface. The minimum visibility when there is a penetration is 3/4 mile. The dashed line missing on the missied approach is a charting error. I will notify the charting people about this so it can be corrected. The feeder route was removed by ATC request. The planview note no longer says "ADF REQUIRED" since there's no longer a procedure entry to the LOM. The DME required was added because the approach starts at the end of a STAR and DME or RADAR can be used to get to FIRPI. I hope this answers your questions. Plese contact me if you still have questions.

Regards,
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Everskyward said:
Got an answer pretty quick.
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Yeah. Doesn't really answer how you get there from the STAR if you go NORDO though.

I just checked, every single STAR to KAPA says "Expect RADAR Vectors" except the RNAV ones. Only the RNAV ones have specified Lost Comm procedures.

So the plate really should say "RADAR Required". DME is only useful if you file a STAR and all the STARs say "Expect RADAR Vectors".

They built a logic loop. How stupid is that!? LOL!
 
denverpilot said:
Yeah. Doesn't really answer how you get there from the STAR if you go NORDO though.

I just checked, every single STAR to KAPA says "Expect RADAR Vectors" except the RNAV ones. Only the RNAV ones have specified Lost Comm procedures.

So the plate really should say "RADAR Required". DME is only useful if you file a STAR and all the STARs say "Expect RADAR Vectors".

They built a logic loop. How stupid is that!? LOL!
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You have the email address above if you want to ask the question.
 
N801BH said:
Wow.... I am impressed at the fast response..:yes:;)..
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In terms of dealing with government employees, the charting folks are the absolute best. I've brought up several issues with them and always got a quick, accurate, and thorough response, and if they weren't the people to deal with it they always both forwarded my message to the appropriate folks *and* told me who the appropriate folks were and gave me their contact info.

In fact, most of my dealings with the FAA have been similar (maybe because I don't have an SI medical), but the charting people are really top notch.
 
Got another email from them.

Dear Mari:

IFP Information Gateway Instrument Flight Procedure (IFP) Project Stage/Status Change: to DEV

This is a courtesy notification that the ILS OR LOC RWY 35 R AMDT 9A for APA has been updated.

You can follow this link to view the change(s).

http://www.faa.gov/air_traffic/flig...ocedure.results&tab=productionPlan&nasrId=APA

Regards,

Production Integration Team
6500 South MacArthur Blvd. ANF-1 Building 5, Room 102
Oklahoma City, OK 73169
Office: 405-954-3027
9-AMC-Aerochart@faa.gov
Visit AeroNav Products Here
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I went to the link and I see that Amendment 9A is now under development and scheduled to be published 2/5/2013 but I don't see what exactly is under development.
 
I haven't heard a thing back regarding the /A questions. But perhaps "Under Development" is a good sign...?
 
denverpilot said:
I haven't heard a thing back regarding the /A questions. But perhaps "Under Development" is a good sign...?
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Hope you've registered at the FAA coordination site and have "notify me" for APA turned on.
 
Reply today...

"Control Number 15881 has been assigned to this issue for tracking purposes.
This concern has been closed with the following Response:

A P-NOTAM has been submitted to change the note to "RADAR REQUIRED."

Still no way to file to get to the approach... Hmm.
 
denverpilot said:
Reply today...

"Control Number 15881 has been assigned to this issue for tracking purposes.
This concern has been closed with the following Response:

A P-NOTAM has been submitted to change the note to "RADAR REQUIRED."

Still no way to file to get to the approach... Hmm.
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If it's changed to RADAR REQUIRED you could file FQF direct KAPA. That's how you end up if you are on a STAR only they give you radar vectors before getting to FQF
 
Everskyward said:
If it's changed to RADAR REQUIRED you could file FQF direct KAPA. That's how you end up if you are on a STAR only they give you radar vectors before getting to FQF
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True. Just leaves ya with no plan that'll still get ya to APA if the radio quits. Normal for a lot of stuff around here, so no big deal I guess.

Also removes the obstacle clearance the old transition route assured from FQF to CASSE.

Pretty much gives the feel that planners have forgotten that the overall Airway to Terminal Area system was truly engineered for Lost Comm. Not so much anymore.
 
New, happy followup to this issue.

FDC 2/6105 - FI/P IAP CENTENNIAL, DENVER, CO.
ILS OR LOC RWY 35R, AMDT 9...
S-ILS 35R VISIBILITY ALL CATS 1/2.
CHANGE PLANVIEW NOTE TO READ: RADAR REQUIRED.
CHANGE INOP NOTE TO READ: INOPERATIVE TABLE DOES NOT APPLY TO
S-LOC 35R.
DELETE NOTE: VISIBILITY REDUCTION BY HELICOPTERS NA.
THIS IS ILS OR LOC RWY 35R, AMDT 9A. WIE UNTIL UFN. CREATED: 19 DEC 18:48
2012
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Of course they didn't issue the NOTAM until yesterday, which was the first day that it impacted the 135 operators since the visibility was down to 1/2 mile in snow for much of the morning. I was glad we weren't scheduled to arrive until the afternoon. The actual chart is supposed to be updated on the March 7 publication schedule.
 
Ok, so two questions:

1) What do they mean by "penetration in 20:1 to final" or whatever the exact wording is?

2) Why'd they then change it back? Did this penetration go away? And what exactly was it?
 
Ted DuPuis said:
Ok, so two questions:

1) What do they mean by "penetration in 20:1 to final" or whatever the exact wording is?

2) Why'd they then change it back? Did this penetration go away? And what exactly was it?
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Unsubstantiated rumor has is that it was a typo on the chart. This suspicion is reinforced by the fact that the DA remained the same plus the fact that there are two new LPV approaches (Y and Z) to the same runway with 1/2 mile visibility minimums. We can't do LPV approaches in any of our airplanes. They are not equipped nor are we authorized at this point.

Of course if someone has an official explanation it would be nice to hear it.
 
Fuuny how your... What, $15 mil jet? Doesn't have WAAS but the little bug-smashing 310 does. :)

The explanation makes sense.
 
Ted DuPuis said:
Fuuny how your... What, $15 mil jet? Doesn't have WAAS but the little bug-smashing 310 does. :)

The explanation makes sense.
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The cost for the upgrade to WAAS is supposedly in the $70,000 range for our airplane. We may get it yet but who knows. The decision is way above my pay grade. Others in our fleet don't even have the option.
 
Everskyward said:
The cost for the upgrade to WAAS is supposedly in the $70,000 range for our airplane. We may get it yet but who knows. The decision is way above my pay grade. Others in our fleet don't even have the option.
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As I recall, the Sovereign is a Part 25 aircraft, and the requirements for everything in that are significantly stricter than Part 23. Something like a second FMS required, etc. It all gets more complicated, and therefore more expensive.

For the 310, upgrading to WAAS meant sending in the 530, changing the antenna cable, and putting on a new antenna.
 
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