Darker ILS "beam"

AggieMike88 said:
I believe the OP is referring to the profile view.
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Yes.

This is the part I'm referring to:

21or0ax.jpg
 
This explains why this isn't mentioned in any book.

Thanks
 
akpilot907 said:
I bet you the dude that published this approach said, "HA! this'll confuse 'em, maybe even get a thread on a forum"...:goofy:
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LOL

Would certainly hate to be confused by that when flying the actual approach in IMC and low on fuel.
 
Hmmmm, if you zoom way in on the PDF it actually looks like there are two glideslope symbols stacked on top of each other:

Perhaps it means something like glideslope isn't shown even close to scale? I can't find any reference to it so I suspect it's a mistake.
 

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Where are all the instrument instructors,with some input?
 
frfly172 said:
Where are all the instrument instructors,with some input?
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I don't think there IS any input. I think it's pretty clearly just a darker "font" or whatever, if you will. There's nothing in the Aeronautical Chart User's Guide for "darkness of ILS feather". Probably someone in charting accidentally picked the wrong line weight for the feather somehow, and it made it through QA, because, really, viewing it by itself, it's not easily noticed.

Or, possibly, it WAS caught in QA, but due to deadlines or whatever they decided not to bother with sending it back through the cartographer, because after all, who's going to notice such a thing? (Obviously not counting on the sharp eye of Machfly.
 
It certainly is different. Quite frustrating that the chart would be like this even if it were noticed. Given the fact that MANY distinctions on aeronautical charts are made by shading.

As TehMightyPirate said it looks like it is a regular glide slope with another darker yet slightly smaller glide slope atop it.
 
RussR said:
I don't think there IS any input. I think it's pretty clearly just a darker "font" or whatever, if you will. There's nothing in the Aeronautical Chart User's Guide for "darkness of ILS feather". Probably someone in charting accidentally picked the wrong line weight for the feather somehow, and it made it through QA, because, really, viewing it by itself, it's not easily noticed.

Or, possibly, it WAS caught in QA, but due to deadlines or whatever they decided not to bother with sending it back through the cartographer, because after all, who's going to notice such a thing? (Obviously not counting on the sharp eye of Machfly.
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It's still the same in Cycle 1313.
 
I suspect the difference is an artifact of using color printing for the Reno plate.
 
Does anyone have access to the same plate that has expired already? Curious if the ILS is the same color on an older plate.
 
I don't understand the profile view.

Do you intercept the glide slope at CEVAP, where there's a bend in the thick black line? That's a whopping 14.2 NM from the runway.

Or do you wait to intercept it at the non-precision FAF, JEBMI, after stepping down twice to 7000'? If so, then you hardly use the glideslope because you level out, at an MDA of 6425, after a descent of less than 600'. After that, there's a very long visual portion of the approach -- are you required to have the airport environment in sight at the MDA, or just the ability to fly visually? And why would they bother providing a glide slope if you only use it to descend 600' before you must be visual?

BTW, neither the Aeronautical Chart User's Guide nor the Instrument Flying Handbook mentions different kinds of glide slope markings, dark vs. light, for ILS.
 
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RussR said:
I don't think there IS any input. I think it's pretty clearly just a darker "font" or whatever, if you will. There's nothing in the Aeronautical Chart User's Guide for "darkness of ILS feather". Probably someone in charting accidentally picked the wrong line weight for the feather somehow, and it made it through QA, because, really, viewing it by itself, it's not easily noticed.

Or, possibly, it WAS caught in QA, but due to deadlines or whatever they decided not to bother with sending it back through the cartographer, because after all, who's going to notice such a thing? (Obviously not counting on the sharp eye of Machfly.
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I agree with Russ... When I use to make maps for non-profits in high school, I would often find small mistakes like this that I had made in previous versions. Either I was close to a deadline and over looked it or I got distracted by something and click the wrong shading. :D

However, you will be surprise by people coming up to you later and say "Hey does this being dark, different shade, color etc... mean anything ?" I would look at it and go nope my mistake. :idea:
 
NoHeat said:
I don't understand the profile view.

Do you intercept the glide slope at CEVAP, where there's a bend in the thick black line? That's a whopping 14.2 NM from the runway.

Or do you wait to intercept it at the non-precision FAF, JEBMI, after stepping down twice to 7000'? If so, then you hardly use the glideslope because you level out, at an MDA of 6425, after a descent of less than 600'. After that, there's a very long visual portion of the approach -- are you required to have the airport environment in sight at the MDA, or just the ability to fly visually? And why would they bother providing a glide slope if you only use it to descend 600' before you must be visual?

BTW, neither the Aeronautical Chart User's Guide nor the Instrument Flying Handbook mentions different kinds of glide slope markings, dark vs. light, for ILS.
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You intercept the glideslope at CEVAP. As far as I remember the ILS is supposed to work about 18nm out.
 
More that I don't understand about this approach:

Why is the visibility requirement a more demanding 3 SM for the ILS approach, but only 1 1/4 SM for LOC and Circling, if you're in category A or B?
 
MachFly said:
You intercept the glideslope at CEVAP. As far as I remember the ILS is supposed to work about 18nm out.
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Okay, I found this in the AIM:

The glide slope is normally usable to the distance of 10 NM. However, at some locations, the glide slope has been certified for an extended service volume which exceeds 10 NM.
 
NoHeat said:
More that I don't understand about this approach:

Why is the visibility requirement a more demanding 3 SM for the ILS approach, but only 1 1/4 SM for LOC and Circling, if you're in category A or B?
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Looks like the DA is about 300ft lower than the MDA. Since your operating close to mountains, extra 300ft may make a significant difference which would require extra room for error, therefore increasing the vis to 3sm.
At least that's how I understand it.
 
NoHeat said:
Okay, I found this in the AIM:

The glide slope is normally usable to the distance of 10 NM. However, at some locations, the glide slope has been certified for an extended service volume which exceeds 10 NM.
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Your right. The localizer is 18nm, the glide slope is 10 or more.
 
NoHeat said:
More that I don't understand about this approach:

Why is the visibility requirement a more demanding 3 SM for the ILS approach, but only 1 1/4 SM for LOC and Circling, if you're in category A or B?
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Precision minimums are based on distance of DA point to runway. That is the case everywhere. It only becomes apparent with a high DA.
 
MachFly said:
You intercept the glideslope at CEVAP. As far as I remember the ILS is supposed to work about 18nm out.
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The localizer is effective out to 18nm, the glide slope is only 10nm

edit: Ooops, someone already beat me to the punch, sorry! But yes, I agree with you all... Anyone know how far out a PAPI is effective? hmm, hmm? :idea:
 
akpilot907 said:
The localizer is effective out to 18nm, the glide slope is only 10nm

edit: Ooops, someone already beat me to the punch, sorry! But yes, I agree with you all... Anyone know how far out a PAPI is effective? hmm, hmm? :idea:
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4 miles unless further restricted in the A/FD. 4 miles is the obstacle clearance limit. You may see it a lot further out, especially at night.
 
akpilot907 said:
The localizer is effective out to 18nm, the glide slope is only 10nm

edit: Ooops, someone already beat me to the punch, sorry! But yes, I agree with you all... Anyone know how far out a PAPI is effective? hmm, hmm? :idea:
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Keep in mind those are standard limits. Flight inspection will extend those limits if necessary to support the IAP.
 
Yeah, I noticed the "fly visual" portion is almost all of the approach.
I suspect the unusual nature of the instrument approach somehow triggers a "shady" glideslope symbol.
 
nosehair said:
Yeah, I noticed the "fly visual" portion is almost all of the approach.
I suspect the unusual nature of the instrument approach somehow triggers a "shady" glideslope symbol.
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Other 'fly visual to airport" ILS approaches don't have that. The Jepp chart doesn't have that either.
 
aterpster said:
4 miles unless further restricted in the A/FD. 4 miles is the obstacle clearance limit. You may see it a lot further out, especially at night.
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Wally,

Do you have any idea why with a PAPI, the OCS is 4 statute miles and not measured from the threshold, but a point 300 feet in front of the PAPI location. This makes the protected area just under 3.4 NM from the threshold. OTH, a VASI is 4 NM from the threshold or close enough for government work.
 
I asked AeroNav. They decided the darker color was an error and will correct it. I doubt it is a high priority, but you might want to check again in January of 2014.
 
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