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FMC airway problem

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For reference, I'm using the PMDG 747-400X in FSX Acceleration. I have AIRAC 0805 installed for the PMDG FMS.I was planning a flight from Amsterdam Schiphol (EHAM) to Tokyo Narita (RJAA). I used RouteFinder (http://rfinder.asalink.net) to create a route and export it to PMDG 744 format, but found the FMC wasn't loading it correctly.I tried to enter the route manually, but still ran into problems. It refused to accept certain fixes as being part of an airway. I manually checkedthe wpNavRTE.txt file, and it did list these waypoints on those airways.For example, one leg of the route created by RouteFinder was RINOV B954 ULDD. I have the previous leg to RINOV entered correctly. Then I type B954 enter it into the VIA field, type ULDD, try to enter it into the TO field but get "INVALID ENTRY" as a result.The thing I noticed that for those particular fixes that had problems, it would accept none of the airways that the wpNavRTE.txt file claimed they were part of. All the other fixes on the airways worked fine. So it's clearly something with the fixes, not the airways.The fixes that had trouble were ULDD, UERP and UHHH. The thing they have in common is that they are all airports. None of the other fixes on the route were airports.So it appears that the FMC has trouble accepting waypoints that are also airports as part of an airway.Is there any fix for this? I can work around it by entering the fix before the airport instead and then going DIRECT to the airport fix, which works but it's a bother and obviously is not possible when loading a RouteFinder exported route.Thanks in advance for any help you can give.

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Please sign your posts with your real name per forum rules.The 744's FMC doesn't actually allow you to use ICAO airport codes as waypoints within the route - just the ORIGIN and DEST on the RTE page.

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"The 744's FMC doesn't actually allow you to use ICAO airport codes as waypoints within the route - just the ORIGIN and DEST on the RTE page" - which seems odd. I don't understand why the FMC is first checking a waypoint entry on the route page to see if it matches any known ICAO code? The expected behavior is that once we enter RINOV, and then via B954, then the FMC would first verify that RINOV is a member of B954, then accept any of the below listed fixes as members of the group B954, including ULDD or UOHH.B954 001 MZ 65.866667 44.200000B954 002 DELIL 66.650000 45.426667B954 003 RAPAD 66.911667 45.860000B954 004 ANEPA 67.405000 46.705000B954 005 RINOV 68.785000 49.316667B954 006 IRDIS 69.398333 55.508333B954 007 ULDD 69.763333 61.563333B954 008 DISON 70.490000 65.843333B954 009 MININ 71.698333 76.498333B954 010 KOMBI 72.086667 82.733333B954 011 AGAPA 72.216667 86.491667B954 012 LOGAT 72.276667 91.898333B954 013 UOHH 71.968333 102.488333Please explain.

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>The 744's FMC doesn't actually allow you to use ICAO airport>codes as waypoints within the route - just the ORIGIN and DEST>on the RTE page.Uh, uh....sorry ?Are you talking about the PMDG's 737 and 747 ?I don't know about the real thing, but I can enter airports as waypoints in both FMCs without any problem.Jose Luis.

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This is strange... now at home and checking the problem entering a fix named same as ICAO airport name. Using noname's example, I cannot enter via B954 to ULDD (ULDD is a valid fix name in the navdata route list for three routes), but I can enter via DIRECT to ULDD.I wouldn't expect the program to behave this way, but it does.The solution, in this case, is to lookup the fix on the airway before the desired fix, use it to establish a route up to that point, then via DIRECT to the desired fix. But assuming the flight plan joins one of the two other airways at this fix, the same method needs to be used because the FMC will not accept a valid airway number at a fix name that is same as an ICAO airport. In other words, look up the next fix on the desired airway, use it to establish a route on the airway by using via DIRECT, then finally join the airway.This becomes (e.g. RINOV B954 ULDD B153 OBERI):RINOL B954 IRDIS ULDD LITKE B153 OBERIRyan: Can you provide a rational reason why a fix name that is also an ICAO code is rejected and an airway cannot be joined at at a fix that is also an ICAO code? The work around is pretty awkward, requiring direct routing to previous and next fixes to join airways.I can't even imagin why such a filter was written into the FMC code to begin with.... does it serve a purpose?

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I had something like this before, and please forgive doing it from memory as I'm away from my set up.On RTE page 2, I tried building a route, say, from ALPHA to BRAVO along airway C123. ALPHA was already in as a waypoint on a right hand LSK. I then typed in the airway C123 and tried to input it at the left hand LSK below, but it wouldn't accept it. So I entered point BRAVO under ALPHA on the right and two things happened; it accepted it and DIRECT appeared on the left hand side. Now I entered the airway C123 over DIRECT and it now accepted it. It looks like you have to build the points before connecting them with the relevant airways.As I said, I apologise if I've got this wrong but I'm away from the home computer just now.David "jumbojock" Robertson

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Just tried David's method in both the FS9 737 and the FSX 747, but it doesn't accept the airway. On RTE page 2, I want to be able to enter RINOV B954 ULDD so using the above method I enter RINOV and ULDD below it and yes, there is a DIRECT but when trying to enter B954 over the DIRECT to replace it, the FMC returns an INVALID ENTRY message (but as mentioned, ULDD is on B954 but is also an ICAO code for an airport). B954 isn't a straight leg, so the DIRECT can't subsitute.This is silly.

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FYI, I tried entering the route using the same AIRAC into the FMC of a 767 from a different developer. I had no problem with any of the legs of the EHAM-RJAA legs that routefinder came up with, including those where waypoints are airports, so it most likely is not a problem with the AIRAC.I'm not a RW pilot, so I don't know which FMC implementation is correct, though.Tom

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I'm not a RW jet jockey either, but the PMDG version of the FMC is acting inconsistent so that's the suspect. However, it took a long time to find this... most airspace authorities don't use an airport reference as an airway fix for whatever reason (I can think of several); but, we're talking about a far corner of the world here.

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