Holding at IMP?


#1

KSAN is fogged in early this morning, and a FedEx coming from KPHX looks like it’s doing a racetrack by IMP…something I’ve never heard of before. I’m gonna bet he’s waiting for the FedEx from KOAK to make or miss the ILS 9.
flightaware.com/live/flight/FDX2 … /KPHX/KSAN
The one from Oakland arrived in the area still in the flight levels…then did a couple circles as well while descending to 15,000. Then they got the vectors to the ILS 9. It appears they actually made it in, even though the current weather says 100’ scattered. KSAN had been reporting vertical visibilities off and on throughout the night, which is never a good thing obviously.


#2

5 laps = about 20 minutes hold time, not too bad…

Does KSAN experience fog a lot? If not, what you say would be reasonable, it would be unusual for a weather induced hold.

Otherwise, this type of event is not unusual in the usual fogged in areas of the country.

What I do find unusual is looking at the ILS approach into KSAN

flightaware.com/resources/airpor … RWY+09/pdf

The minimums are unusually high. My experiences are that ILS will let you go down to 200 AGL, where as this one is 336 AGL.

Does anybody know why the higher minimums for all categories???

Glide slope intercept and descent angles look normal and I don’t see any obstructions to warrant the higher minimums?

Allen


#3

From answers.com

The vast majority of operations at SAN are to the west.

Landing at the airport from the east (the most common approach) offers dramatic closeup views of skyscrapers, Petco Park (home of the San Diego Padres), and the soaring, curving Coronado Bridge from the left side of the aircraft. On the right, Balboa Park, site of the 1915-1916 Panama-California Exposition, can be seen, along with the world famous San Diego Zoo and several freeways.

The approach from the east is steep, necessitated by terrain which drops from 266 feet to sea level in less than a mile. Aircraft normally descend at 317’ per mile, but in San Diego they must descend at 376’ per mile. San Diego’s only runway is located at the base of a hill lined with several obstructions, including the I-5 freeway and trees in Balboa Park. Contrary to local lore, the parking structure off the end of the runway was built long after previous obstructions built up east of the I-5. The parking structure was then built up to this controlling limit. Aircraft clear the parking structure by the required 109 feet. Aircraft arriving from the east do not land at the end of the runway as at most airports, but land at what is called a displaced threshold, located 1810 feet from the runway end, effectively shortening the landing distance to 7591 feet. Aircraft departing to the west use the east end of the runway as their departure point. A photo from the cockpit of an arriving aircraft clearly shows the approach and the displaced threshold.


#4

Again, all in the details my friend…

This above reference explains runway 27 operations (from the east - to the west), does not explain the ILS 9 to the east, (from the west to east operations). It explains the displaced threshold on landing on runway 27, it does not explain the higher then normal landing minimums of a normal 200 feet AGL for an ILS approach for runway niner.

However that caveat in mind, you may have brought out an interesting point.

The glide slope on the ILS at KSAN is 3.22 degrees for runway 9 as compared to 3.00 normal ILS approach per faa.gov/airports_airtraffic/ … m0101.html 1-1-9 D 3

which makes me think the above reference credibility needs to be brought into question as it appears to me, it’s directions are backwards or something not annotated on the approach plate I provided warrants a steeper then normal approach that the above reference doesn’t explain.

There are no ILS approaches for 27 based on
flightaware.com/resources/airpor … procedures and the above may explain why no ILS is availibe for runway 27 due to terrain.

All the other approaches are “dive and drive” from the east to the west (Localizer and GPS approaches have no glide slope) so a steeper then normal descents are normal.

So, the question still remains, why is the minimums for the ILS 9 at KSAN higher then the standard 200 feet AGL. Could it be due to the steeper then normal descent profile of 3 degrees???

Allen


#5

Try clicking on the link and reading the rest of the article, my non-friend. I’m not going to quote the entire article here. The part I did quote explains the steep approach to the runway that is used most of the time.


#6

Ahh, but you posted as if to answer my question??? If that was the case, it does not.

If you could please answer my SPECIFIC question regardind the ILS approach 9 with a credible reference, or based on some type of experience like having flown that approach, that is what I am looking for, not a general non FAA type of reference. I didn’t ask what was the most commonly used approach at KSAN

As far as reading the rest of the article, I did read it and all it does is explain the departure procedures of runway 9, NOT THE ILS question that I posted.

Details my friend…

Allen


#7

Obviously you need everything handed to you on a platter.
If you would fully read the article and the references contained in it, you would find your answer.

Look at the references carefully. There is a reference to the FAA Master Record (form 5010) for SAN. Go to that reference. Click on the Remarks Tab. Look for “RWY 09 APCH RATIO 44:1 TO DSPLCD THR.” This translates to Runway 09 has an approach ratio of 44 to 1 due to a displaced threshold".

Okay, so what, you say. What does this have to do with my question? It still doesn’t explain about the ILS approach to 09 at SAN. Well, yes it does. The higher than normal slope is due to the displaced threshold.

AC 150/5200-35


#8

The ILS 9 minimums are higher than standard due to the higher terrain on the final approach course. The terrain of the Point Loma neighborhood at it’s highest point where the final approach course crosses is 160 ft msl at 1.25 NM from the RWY 9 threshold which is 14 ft msl. That calculates to a 1.92 degree rise from the threshold to that highest point.

And as information, the indentifier for the Imperial VOR is IPL. :wink:


#9

**Again, you are missing the details, **and why should I be surprised as you still have answered my question INCORRECTLY.

Displaced threshold has NOTHING to do with minimums on an instrument approach, Available landing distance yes, minimums NO. You do know what a displaced threshold is? Minimums are based on OBSTACLE clearances.

Further more, a displaced threshold will REDUCE the angle of glide path as you are landing further down the runway…

If you would look at the FAA charts in my link, that will confirm what I am talking about.

**Azav8r gave me the answer I was looking for. ** Thanks Azav8r!!!

The answer based on what I understand from Azav8r comprehensive reply is that the terrain is too close to the standard glide slope causing a need a higher descent glide path to avoid what is poking out of the ground., thus raising the minimum Height Above Airport (HAA) on the approach course.

And his answer was in only 18 words (first sentence).

Allen


#10

I finally see what the hell you were talking about. With all of the quoting inline, highlighting, etc., it is easy to miss some of what you say.


#11

I shouldn’t feed into this but you really got me curious…

What part of

**Does anybody know why the higher minimums for all categories??? **

was confusing in my question?

I really thought it was a very clear and concise question.

azav8r answered it in one paragraph clearly and concisely in ONE post.

NOT one of your replies answered this question.

I ask this so I can improve on the clarity of my questions for future reference.

Allen


#12

YOu didn’t quote yourself fully:

Notice that I highlighted “ILS” in your quote above so I went looking for ILS minimums, not plain ol’ minimums.


#13

[quote=“damiross”]

Also, please reread my ORIGINAL question in my ORIGINAL POST, as I did fully quote myself. Your reply and subsequent replies were incorrect responses.

You were not even in the same league much less same ballpark of even coming close to an asnwer to the question. I knew this from my training and experiences and I have never been near KSAN.

With this behind me, now, lets fast forward to me re-iterating my question in the following post you replied that apparently is confusing to you. Please note what I am highlighting in red below.

It’s all up there if you don’t believe what I am typing, so use your scroll bar to refresh your memory please.

What part of

So, the question still remains, why is the **minimums **for the **ILS **9 at KSAN higher then the standard 200 feet AGL.

was confusing again???

I really think my questions were as clear as the sun rising in the east. All I did here is copy from what you quoted me, added a little red for emphasis, and didn’t change a thing. Did you by any chance miss the word minimums???

I didn’t ask about displaced thresholds in any of my questions and as you are now apparently discovering displaced thresholds have nothing to do with approach minimums on an FAA instrument approach chart.

So again, pleae enlighten me where I may have confused you as none of your replies pertained to instrument approaches nor did they give any correct answers to my question.

Now maybe you can see why I ask so many questions about your credibility when you make strange responses to a question on a topic that I have to have a very strong knowledge on as this is a topic that I have to be very literate in since my life depends on it when I am in IMC???

Allen


#14

Why can’t you just drop it? Why do you always have to be right? I told you I misunderstood the question but you have the insatiable urge to say in paragraphs of dozens of words each exactly why I was wrong and exactly why you were not wrong.

In other words, my non-friend Allen, shut up. Accept winning graciously.


#15

336’? Wow they changed it then. It used to be 550 I think. As far as runway 27 minimums, it’s 660’ for the Loc and the RNAV, which happens to be the MDA for the last minute or so of the approach.
Yes, we do get fog occasionally, especially when a Santa Ana-type wind condition gets kicked out. When OFFshore flow gets replaced by ONshore flow, it almost always comes by way of fog for a while, then slowly lifts. Just look at the past 24 hours wx @ KSAN (starting around 0700Z on the 13th) and you’ll see it there. It had started to lift from VV001 to OVC006 as those FedEx guys were getting in.
Sometimes they will run the ILS 9 due to clouds, yet depart on 27 due to winds. That’s when it gets messy because everyone gets delayed… I bet we could fill another thread with those stories.
Finally, whoever informed me on the correct ident for Imperial VOR, thank you. I ALWAYS get that messed up! I will now go to the chalkboard and write “Imperial VOR is ‘IPL’” a hundred times. 8)
And Allen, to answer your question, the reason for the higher approach minimums is solely terrain. We will likely never see a Cat II/III system at this airport, and I haven’t heard any word as of yet, on whether a WAAS will be installed.
Here’s a typical landing on a clear day at KSAN. You’ll see the terrain issues. https://www.youtube.com/watch?v=-R2vr6uG9W8)


#16

[quote=“QuickBurn”]

Here’s a typical landing on a clear day at KSAN. You’ll see the terrain issues. https://www.youtube.com/watch?v=-R2vr6uG9W8)

Wow, a pic (or should I say a video) worth a thousand words. THANKS!

Allen[/quote]


#17

The generic answer is: (I agree that climb gradient is the most likely reason at KSAN)

  1. Obstacles in the approach area near the end of the runway.
  2. The electronic signals are only within tolerances down to published minimums.
  3. Obstacles in the missed approach area requiring either a steeper than standard climb gradient or higher approach minimums. Check out KJAC.

I held on the ground at SAN during a foggy morning once years ago, the weather was below BC 27 minimums so they were landing on 09. But the kicker was that most of the airlines could not make the climb gradient required for a 09 takeoff so they would run 10 arrivals onto 09, then hold all arrivals while they departed 10 aircraft off of 27. Quite a backup until the fog lifted.


#18

Good point, gotta consider the missed options as well, and it makes sense to raise the minimums to reduce the climb gradient on a missed approach. KJAC does have a standard ILS approach descent rate of three degrees.

One thing for sure, after looking at KJAC I won’t be flying into that field.

Their field elevation is in the higher range of my cruise altitude :smiley: and the service ceiling of my Sundowner is 12.6K myplaneonline.com/bmo/index. … _specs.cfm

180 ponies, just “ain’t” going to cut it!

Allen


#19

I’ve been to SAN a couple of times, luckily the weather was good both times. I like to call the approach the “Garage Visual” It’s a beautiful area, and a pretty cool approach. Definitely have to be on your toes though, because the tendency is there to get low.

My theory on the “nonstandard” (200 ft. vs. the usual 150 ft.) runway width is to give pilots the illusion that they are lower than they are, giving them a couple extra feet to stay over some of the stuff.

As for the painted green runway border I have no theory on that one.


#20

I am going there on March 12th as a “passenger” Which side of the plane is better to sit on?

Thinking of taking SWA so I can select a seat on the day of flight :smiley: or may take Delta as it takes a little less time to get there even though I have to go east to go west.

Allen