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KLGA Star problem/s

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Greetings to the PMDG community....I keep having a problem with the Korry3 KLGA STAR procedure. The problem is that few if any of the crossing altitudes are remotely correct in the onboard FMC. For instance, the BEUTY waypoint is supposed to be crossed at 10000ft/250 kts. When I review the LEGS page of the STAR, BEUTY is consistently reported to be crossed A8000 instead of 10000 ft. The same goes for most of the other altitude crossing points for this STAR. I have updated all the AIRAC files and other NAV files yet this continues. I even reviewed the latest AIRAC file folder for KLGA and sure enough, BEUTY was listed as to be crossed at 10000 feet. So obviously the problem does not lie there. I end up having to manually alter all the descent waypoints which I can do but it seems alot of work to do for no apparent reason. I understand we may have to alter some waypoints for ATC reasons, but all of them?There are two questions I have regarding this problem. First, does anybody's FMC report the Korry3 arrival BEUTY crossing point as 10000 feet and not A8000? I wonder if my setup is wrong somehow. Second, what is the source for crossing altitude restrictions as used in the FMC? By this I mean the folder inside the PC with this information. I suppose it is the PMDG/SIDS/STARS folder but I am not sure. I just want to know where the A8000 feet crossing restriction came from.Thanks in advance, Joe Swier

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Guest pagotan

Hi Joe,Unless I cannot read the procedures correctly I think there is a confusion here.You are stating that the BEUTY fix should be crossed at or above 8000. This is correct but there is no BEUTY fix in the KORRY3 Star. You can find a fix BEUTY with the correct altitude restriction in the MIP3 Star.Here are the two stars for your guidance:STAR KORRY3 FIX ENO AT OR ABOVE 24000 FIX SKIPY AT OR ABOVE 19000 FIX BESSI AT OR ABOVE 17000 FIX EDJER FIX DAVYS AT OR ABOVE 13000 FIX HOLEY FIX BRAND AT OR ABOVE 11000 FIX KORRY 10000 FIX RBV FIX TYKES FIX MINKS FIX RENUE FIX APPLE FIX PROUD TRANSITION AGARD FIX AGARD FIX SPEAK TRANSITION GVE FIX GVE FIX COLIN FIX PXT FIX GARED FIX RIDGY AT OR ABOVE 27000 TRANSITION PXT FIX PXT FIX GARED FIX RIDGY AT OR ABOVE 27000andSTAR MIP3 FIX MIP AT OR ABOVE 18000 FIX MARRC AT OR ABOVE 13000 FIX BILEY AT OR ABOVE 13000 FIX VIBES AT OR ABOVE 13000 FIX FJC AT OR ABOVE 13000 FIX LIZZI AT OR ABOVE 9000 FIX BEUTY AT OR ABOVE 8000 FIX HARLM AT OR ABOVE 8000 FIX DREMS AT OR ABOVE 8000 FIX APPLE AT OR ABOVE 3500 FIX PROUD AT OR ABOVE 2500 TRANSITION ETG FIX ETG TRANSITION PSB FIX PSB TRANSITION SFK FIX SFKOn a more general note I would assume you are using the procedures released by Terry available either from the PMDG website or from Terry's site. If not so I would strongly recommend you download the latest cycle of the PMDG procedures from one of the above sources. The reason I recommend this is that Terry's procedures are derived from DAFIF datas which are very accurate for US airports. My point is that if your procedures are up to date and from the above sources you sohuld have the most accurate speed/altitude restrictions. So what you will read in the FMC when validating the procedure are the correct altitudes and speeds.I hope this helpMerry ChristmasMichael

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Thank you Michael and Merry Christmas to you as wellObviously I needed to drink more coffee or at least mix more caffeinated into my java blend......DOH! I was in error when I said the STAR was the Korry3, I meant to say the Milton 3(MIP3) arrival. Thanks for the correction. But the point was still the same-I am supposed to cross BEUTY at 10000 ft and not at or above 8000 feet.Yes, I realize that 10000 feet is above 8000 feet, but if I don't manually edit the STAR then I may cross BEUTY below 10K and bust an ATC restriction. I guess I could plug in 10000 feet into the A/P and I would not descend below that, but the STAR plate clearly says 10000 feet at BEUTY. It does not states anything remotely like at or above 8000 feet. I can't see how this is correct. Are you saying that if I don't alter the STAR leg for BEUTY that I will cross it over 10000 feet? I never tried that because I have found that in the PMDG 737 if a waypoint crossing alt is to be crossed "at or above " 14000 feet for example, the FMC tends to cross that waypoint very near 14000 feet. Therefore, if I fly the MIP3 STAR and the FMC leg page states X BEUTY at or above 8000 feet, in all likelihood I will cross BEUTY near 8000 feet and thats no good. This is my concern. I fly NE US arrivals alot and I want to get this right. I have already updated all the NAV files as per your recommendation, and I have kept them up to date prior to now, so no worries there.Thanks so much for your help....I appreciate it!Cheers and merry christmas......Joe Swier

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So..Why not just enter the restriction you want ? Look at the chart, verify it, change anything that's not right.It happens. Remember, even if the poeple who put the navdata together for us(for free) were perfect, the source data used is not, so this will happen from time to time.

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Guest pagotan

Joe,The chart shows clearly FJC at or above 13,000, LIZZI at or above 9,000 and BEUTY at or above 8,000. This is how the procedures are built. The indication under the details of the BEUTY fix " expect to cross at 10,000'" is not taken into consideration by the routines building the procedure. The routines follow the raw datas from DAFIF which indicate altitude and speed restrictions for each and every navaid when ever applicable. Joe, I am not trying to say that you are wrong but I merely explain how the procedures are built for all addons.I don't know about you guys in the US but here in Asia if there is no further indication from ATC we are trained to follow the charts exactly. So in this case we would go with the procedure in the FMC ie. cross BEUTY at or above 8,000. The "above" in that case should be somewhere between 9,000 the altitude restriction of the previous fix and 8,000. Agreed PMDG has a tendency to get as close as possible to the minimums but you could enter an altitude manually if you feel like or manage the vertical speed to reduce it or change the settings in the Descent page of the FMC speed versus altitude.Does this make any sense to you?Michael

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Thank you Brian and MichaelPlease don't read any criticism of any of our NAV aides.The guys who do them are fantastic, no doubt!Michael, the MIP3 approach plate I have (and its from the FAA) states to cross BEUTY at 10000 feet.Other crossing restrictions for this STAR are MARRC X at or above 18K, VIBES X at or above 13K and BEUTY AT 10000. I guess this is the source of my concern-it clearly states AT 10000 for BEUTY. During ALL VATSIM flights I have been told to cross BEUTY at 10K/250 knots. Where did you understand that the crossing for BEUTY was At or below 8000 ft? It would be helpful if you say where you saw this. My understanding may be wrong and I wish to learn. This was a useful exchange of information for me and I greatly appreciate your time and helpful manners. I also think this is a great learning experience. Cheers again!Joe Swier

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Hi Joe"Where did you understand that the crossing for BEUTY was At or below 8000 ft?"Just to clarify, he did not wrote that, he wrote "AT OR ABOVE 8000" if you look at it again.In addition to what Michael wrote, the "AT OR ABOVE 8000" command must be correct here if you look at the plate, it clearly states 8000. But it also says "Expect to cross (BEUTY)at 10000". And this is as Michael says given by ATC.As I read this the 8000A is the "base" altitude restriction along this segment. Then you have further guidance by ATC to EXPECT 10000 when crossing BEUTY(by ATC). My charts also states that.This editing must(if given)eventually be entered by the pilot directly in th FMC if necessary, not as a restriction in the SID/STAR file, that would be wrong. So I think the procedure you have is correct.You can also delete the 8000A at LSKxR and let the FMC calculate for itself, and if the result then is within any restrictions, this is a good alternative. Or you can as you say insert 10000 as a hard constraint at LSKxR.

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If I may, I'd like to jump in here and add my comments.I'll begin by saying that I'm an Air Traffic Controller with over 18 years experience and a commercial/instrument pilot. Navigation (air and sea) is a hobby.The way I interpret the Milton Three Arrival to LGA from the latest data dated 12/23/04 (0413) is as follows:There are three restrictions on the MIP3 STAR - MARRC at FL180, VIBES at 13,000, and BEUTY at 10,000. There are no published speed restrictions except for the normal 250kts. below 10,000. The altitudes underlying the course lines (13,000 between MIP and LIZZI and 8,000 between LIZZI and DREMS, etc.) are minimum enroute altitudes below which an aircraft cannot descend if for some reason they are pulled off the STAR. The "Expect to cross" altitudes are published so pilots can plan for the descent. It would be my guess that aircraft are cleared to cross all the fix restrictions as published.I have also found that the FMC does not enter the proper speed/altitude restrictions but they are easily amended. If you want to take the time you can correct the problem in the SIDSTAR database.Don Bohr

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Guest pagotan

Hi Don,You are perfectly right about the restrictions and minimum enroute altitude. This is exactly the point. When the procedures are computed from the DAFIF database the routines read what DAFIF feed them with. In our case DAFIF would indicate the minimum enroute altitude for each fix/navaid as the altitude to be at when crossing the fix/navaid. Therefore the 8,000 AT OR ABOVE for the fix in question.Maybe Terry could jump in at this point and tell us whether he plans to amend the routines in the future to pick up the expect to cross altitudes instead of the minimum enroute altitudes.Michael

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Michael:I hate to disagree, but there is no "at or above" 8000'on this STAR unless it is assigned by ATC for ATC reasons only. Pilots cannot arbitrarily use 8000'. Every altitude will be assigned by ATC. If ATC doesn't assign 8000', an aircraft cannot fly at that altitude. Note the restriction on the STAR: "For aircraft capable of 210K IAS or greater", therefore, in all likelyhood, this is a turboprop/turbojet STAR only and these aircraft will be descending for high altitude and not anxious to use 8000'.If Terry doesn't amend the STAR, I can do it and forward it to you.Don Bohr

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Guest pagotan

Don,Sorry for the slight misunderstanding, maybe due to the long night on Christmas eve and early wake up call this morning. What I meant is that the routines producing the procedures from the DAFIF databases interpret the minimum enroute altitudes as a "AT OR ABOVE". I did not want to imply in anyway that this was the correct interpretation in real life. Sure enough altitudes are assigned by ATC and the 8,000 ft level in our case is certainly not at the pilot's discretion. My point all along in this thread has been to try to explain how the database interact with the routines producing the procedures for PMDG. Here we have obviously a clear example of the shortcomings. I suspect however that we will have to live with it for a while because of the extra work it would mean for Terry if he had to reverse automatically generated procedures and fill in the blanks manually.Michael

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Michael:I now see what you were trying to explain. We were working on different sides of the same page.I find it easier to amend the procedures myself, either through the FMC or within the SIDSTAR database. I've run into several other errors, the LOOP departure off LAX being a prime example. Eventually I'll get around to fixing the ones I know are wrong.Merry Christmas and a Happy New Year.Don

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Guest stang

Well here I go, jumping in. Hi all. Interesting discussion going on here. I just checked the DAFIF database and it only has AT or ABOVEs for this STAR. DAFIF does show BEUTY as an AT or ABOVE 8000. I also looked at the paper chart and I can see the EXPECT TO CROSS AT 10000 at BEUTY and it appears to me that the 8000 foot restriction is either an AT or ABOVE or a RECOMMENDED altitude (I looked it up in an FAA symbols pamphlet). This is one of those situations where I am not clear about which to use. I can manually change the database to make it a CROSS AT 10000 but is that what would really show up on a real world preprogrammed FMC? Is a "for planning purposes" altitude a real altitude restriction that would be "hard coded" into a STAR? Or is this a situation where the pilot would change the AT or ABOVE 8000 foot restriction to AT 10000 once they start flying the STAR?Any real world heavy metal pilots out there? Just how would this waypoint altitude restriction show up on an airline's FMC?I can make changes to my database but before I hard code them in I would like a little more discussion about what EXPECT TO CROSS is considered. Is it a real altitude restriction or one to use at the pilots discretion, if not told to do so by a controller?RegardsTerry

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Hi Don>I've run into>several other errors, the LOOP departure off LAX being a prime>example. Eventually I'll get around to fixing the ones I know>are wrong.I am will to correct inaccurate procedures but no one writes to me to let me know about inaccuracies. All I need is a copy (JPG will do) of an official, not homemade, chart in case I don't have it, so I can see the problem. Let me know about the errors you've found and I will see what I can do, within the limitations of the language of course. My address is in the "Read This First.TXT" file that comes with the procedures.RegardsTerry

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Terry:If you want to send me your private e-mail address, I'll send you two files to show you what I mean.Dondkbohr@pobox.com

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Guest stang

Hi Don. Sure. Address is in the "Read This First" file, 737NG@hotpop.com.RegardsTerry

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Guest pagotan

Hi Terry, >>Just how would this waypoint altitude restriction show up on an airline's FMC?<

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Hi Don, Terry and Michael:Once again my thanks for your help with this thread......I greatly appreciate your help and this GREAT conversation. Terry....I double checked my information and re downloaded a current FAA MIP.3 STAR (dated 23 Dec 2004) # 04050, and the crossing altitude for BEUTY is 10000 feet. Specifically, the instructions state "Expect to cross (BEUTY) at 10000 feet. The STAR also states for MARRC to be crossed AT FL180, and VIBES to be crossed AT 13000. The plates do not have any reference at all for "at or above" altitudes and 10000 feet must be considered a "hard" crossing altitude. There appears therefore to be a discrepancy between sources of information regarding this STAR. I guess I thought/think that the document I named above was the prima facto source. As Don and I had stated, the issue I originally had was that if I followed the FMC STAR as is currently written, I would most likely cross it at around 8000 feet and doing so would violate my alt restriction. To date I had just been manually editing the LEGS page of the STAR during a flight, and thats when I noticed the "issue" with this STAR. Yesterday I went and explored the latest AIRAC nav data info and just manually edited the MIP.3 STAR but have yet to try it out. I plugged in the above hard altitude restrictions so I just have to see how it goes. Terry, it is amazing the amount of information you provide to the sim community......just awesome. It is greatly appreciated too! Without guys like you this sim just wouldn't be the same. Thanks once again......Joe Swier

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Guest stang

Hi Michael and all. >What do you think should be the best approach? to make the >simmer's life easy and have the altitude hard coded or to >stay as close as possible to the real world definitionsI tend to lean toward the real world approach as that is what the 737NG is all about, simulating as close as possible the real aircraft and it's operation. With this particular KLGA example I tend to lean towards taking the approach that "Expect to Cross At" instructions are discretionary not mandatory, unless someone can point me to a document that stipulates it is mandatory. And using your Jeppesen description it would mean that the Expect to Cross At 10000 foot waypoint modifier would not show up in an electronic database so the pilot would have to punch it into the FMC manually in any case. As for the AT and ABOVE 8000, that came from a real world source and I do see the 8000 printed on the chart. In this example I am thinking I should leave it as it is for the reasons above.However, for those that want it hard coded anyway, all you have to do is open the KLGA.TXT file and change the fix "... FIX BEUTY AT OR ABOVE 8000 ..." to read "... FIX BEUTY 10000 ...". Further information about writing SIDs/STARs/IAPs and some troubleshooting hints are in my tutorial at http://home.sw.rr.com/filesherenow/index.html.>Terry, if you are interested I have a copy of the entire directive >from Jeppesen there are many other "exception" listed.Sure. I think it would be interesting reading and good backup material. Thanks.RegardsTerry

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Guest pagotan

Hi,OK, if we take the "real world" approach for this simulation then we should albeit by the real world rules/constaints. As I explained earlier and substantiated with a document from Jeppesen which by the has been approved by the FAA, neither the "Expect to cross at" nor the MEAs "Minimum enroute altitudes" should be hard coded in the procedures. It remains at the pilot's discretion to punch the altitudes following instructions he may or may not receive from ATC.So here if we follow the Jeppesen document and the real world onboard database structure all references to MEA's and Expect to cross should be deleted from all procedures not only KLGA. Terry it's really up to you since you are the only one having access to the routines. But as far as I am concerned the fix BEUTY in our specific example should nor have any altitude or constrain attached to it (neither 10,000 nor 8,000).Document from Jeppesen is on its way to you. You will be amazed by the number of items which are not included in the real world onboard database. If you were to implement only half of the exclusions the writing of procedures for PMDG would be done in a second but sim-pilots may find it over-stressing to have to punch in ATCs instructions. Michael

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Guest pagotan

Hi Ryan,That is an interesting statement. I would assume that UAL codes the "expect to cross at" altitude as guidance only pending ATC clearance. Probably UAL has issued some internal directives to that effect in order to not contradict with established rules.Here are two more exerts from the interpretation of the "expect to cross at" phraseology:Clearance to "descend via" authorizes a pilot's discretion descent to comply with published altitude and/or speed crossing restrictions. "Expect" altitudes/speeds are not considered STAR/FMSP crossing restrictions until verbally issued by ATC. They should be used only for planning purposes and should not be used in the event of lost communications, unless ATC has specifically advised the pilot to expect these altitudes/speeds as part of a further clearance. Source: NATCA ATC briefingandIn addition to the verbal transmissions of what pilots may expect, there are also visual "transmissions" placed on charts for planning purposes. Standard Terminal Arrivals (STARs) and Standard Instrument Departures (SIDs) very often include expected altitudes, expected course guidance, expected speeds, etc. Here again, remember that the printing of those expect values on the charts does not constitute an ATC clearance to descend, climb, turn, etc. If the chart says expect, the pilot still needs a specific clearance from the controller before the action is authorized. However, when the altitudes, routes, speeds, etc., are printed without the word expect, they are mandatory. Profile descent procedures contain good examples of these mandatory crossing altitudes and tracks to be flown, and do not seem to cause nearly as many problems as do the STARs and SIDs. Probably the STARs/SIDs are more often confused because they may contain both mandatory and expect values.Source: ASRS directivesMichael

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I would guess the "Expect" altitudes are placed on an STAR because ATC issues those altitudes a great majority of the time, maybe as high as 90%. There may be occassions when a different altitudes are assigned (pilot request, slower traffic on the STAR, etc.) but I would bet that the assigned altitude would be higher, rather than lower, than 10,000. I just did some flight plan checking and it looks like the MIP STAR is a heavily used route from ORD with aircraft entering the STAR from over Keating (ETG).What we need is for someone to go to Chicage, buy a ticket on UAL to LGA, tune in Channel 9 on the Inflight Entertainment System, and take notes. I'd go myself but it looks much to cold in the east for this California boy. :-sun1 Don

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Guest pagotan

Hi Terry,Have you had a chance to read through the material I sent you? if yes what are your conclusions? If you decide to implement some or all of the exceptions listed please let this community know as more and more simmers are writing procedures. Sofar the manuals to write procedures have focused on syntax rather than on what should be included and what should not. When I look at user written procedures we start to see substantial deviations from the on-board database in real FMCs (not due to PMDG syntax limitations but rather to interpretation of paper charts). Michael

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Guest stang

Hi there Michael. >Have you had a chance to read through the material I sent you? >if yes what are your conclusions? I have finally read through the Jeppesen definitions. First I have to put that document in perspective. It is only a paper that was presented to a seminar back in Apr 2001. This to me says that it is not regulatory and just explains how Jeppesen creates databases and the problems of conversion between the paper product and an electronic database. It even said that some of the ways they do things may change in the future, so nothing said was set in concrete for Jeppesen. The paper was good though at pointing out the problems of creating an electronic database but it also said that various database supplies may do things differently. This opens up the arena for more interpretations. I ask questions to airline pilots from time to time about what is in the FMC database. It seems it is not consistent because airlines can order how they want the database. It would seem that one database will not please everyone even if it accurately mimics a real airline database.In the final analysis I like what Jeppesen said, "Because of the incomplete set of path terminators in some avionics systems, pilots need to ensure their avionics systems will take them on the routes depicted on the charts. If the avionics systems don

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Hi Terry,> I have finally read through the Jeppesen definitions. First I have >to put that document in perspective. It is only a paper that was >presented to a seminar back in Apr 2001. This to me says that it is >not regulatory and just explains how Jeppesen creates databases and >the problems of conversion between the paper product and an >electronic database.Fair enough. Here is a link to the ASRS site with an interesting interpretation especially the paragraph "Expect-ations"http://asrs.arc.nasa.gov/directline_issues/dl4_expect.htmand another one from NATCA where the paragraph 4-5-7 "Altitudes" is worth readinghttp://nwp.natca.net/Administration/Docume...RF.HTM#P0405007This however reamins theoratical in view of the many interpretations by different airlines. Therefore it may be sufficient to list a few reliable documents on this or your sites for writers of procedures. I guess the point is to try to have a common ground for the writers so that users do not get confused when comparing the FMC loaded procedures with paper charts.Michael

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