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Pmdg Fmc - Writing Sids And Stars Issues

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I have been enjoying the amazing functionality and accuracy of the 737 NGX simulation and decided to write accurate approaches not in this months latest Navigraph updates. In particular I have been attempting to write RNAV approaches for Queenstown NZ in the SIDSSTARS folder. I have searched the net for assistance in writing the correct syntax for these files and have been meticulous in adding all extra fixes to the file as well as the approaches and gates. I keep getting an error at line 17 which is the word FIXES. It appears like all other files in this folder and is very confusing.

Is this a known issue when writing your own SIDS stars files?

Does anyone know of a tutorial or summary for writing the correct syntax and the possible command options for writing my own data for the 737ngx FMC?

Rather than starting with the functioning SIDSTAR file for NZQN and updating the file line by line then shutting down FSX then restarting to see if there is an error message in the FMC, is there a program that simulates the PMDG FMC alone so I can check if my newly written files will work in FSX?

This is a very slow process but I would like to fly accurate approaches into my airports of choice in the simulator.

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The World is small  :lol:

 

I am writing at the moment also a SID/STARS File, and getting the same error  :( ERR AT FIXES LN:6 ??

this is strange, if there really would be a mistake in the Fixes section, then the FMC would say it more precisely.

 

btw: you don't have do always reboot your FSX from new, neither the PMDG add-on you use.

Just save the File and enter again your Dep Airport.

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I have been enjoying the amazing functionality and accuracy of the 737 NGX simulation and decided to write accurate approaches not in this months latest Navigraph updates. In particular I have been attempting to write RNAV approaches for Queenstown NZ in the SIDSSTARS folder. I have searched the net for assistance in writing the correct syntax for these files and have been meticulous in adding all extra fixes to the file as well as the approaches and gates. I keep getting an error at line 17 which is the word FIXES. It appears like all other files in this folder and is very confusing.

Is this a known issue when writing your own SIDS stars files?

Does anyone know of a tutorial or summary for writing the correct syntax and the possible command options for writing my own data for the 737ngx FMC?

Rather than starting with the functioning SIDSTAR file for NZQN and updating the file line by line then shutting down FSX then restarting to see if there is an error message in the FMC, is there a program that simulates the PMDG FMC alone so I can check if my newly written files will work in FSX?

This is a very slow process but I would like to fly accurate approaches into my airports of choice in the simulator.

There is a Tutorial how to make Terminal Procedures for PMDG Aircraft this document is made by Terry Yingling, You can find it in the AVSIM File libary search for the following: "PMDG 737NG Terminal Procedures Tutorial 5th Edition ". 

 

Mark.

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G'day to both Mark and DAL521,

 

you have been very helpful. I will check mout the tutorial and feedback hao this goes.

 

Thanks heaps,   Martin.

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I am writing at the moment also a SID/STARS File, and getting the same error ERR AT FIXES LN:6 ??
this is strange, if there really would be a mistake in the Fixes section, then the FMC would say it more precisely

 

The error message will just point to the FIXES line if the error in that section cannot be resolved by the "interpreter."  A good example is a missing ENDFIXES declaration, or "white space" within the fix definitions that is not a space character but something like a tab. Also a misplaced N or W or whatever will confuse the interpreter as to when a line ends and one starts (CR LF characters are allowed within a "line") and it will simply point to the FIXES header.

 

I'm willing to help you get through the learning curve, just quote part of my reply and I'll get a notification that you are directing a comment/question towards me.

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Selective Quote

 

G'day Dan, very much appreciated.

 

In my updated SIDS STAR file for NZQN, I have been running through entry by entry for my additional APPROACHES, FIXES and GATES and did come to the conclusion also that ERROR at the "FIXES" line did mean there was an issue with the syntax somewhere in the file. I verified by checking every new additional fix one by one to see if the FMC showed and error and you guessed it, no error appeared. Also adding gates at the airport did not cause an issue either.

 

I was also experimenting with by writing in one extra fix at a time to see if there was a limit to the number of fixes in an APPROACH line. This did not seem to cause an issue either.

 

What I did find was the use of TRK in the APPROACHES section causes an error and the SIDS/STARS for that airport doesn't appear in the FMC.

 

Now that I can put in many fixes in the approach (making sure I don't use TRK) this helps me write accurate "real world" approaches for NZQN (and others).

 

Are there any other traps in writing the syntax for these files? I have read the "PMDG 737NG How to make Terminal Procedures" from the Avsim library as well as the "Tutorial on how to create and adapt data files for PMDG FMC" by Luca T. I'm pretty sure the TRK issue was not mentioned.

 

Also in the real world approach charts for NZQN (in particular RNAV Y RWY 23) there are smooth arcs required between each fix to navigate safely through the mountainous terrain. By writing FIX OVERFLY this has helped align the approach better but is there a command to place a smooth arc between each fix in the approach??

 

Thanks and regards,   Martin

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The error message will just point to the FIXES line if the error in that section cannot be resolved by the "interpreter."  A good example is a missing ENDFIXES declaration, or "white space" within the fix definitions that is not a space character but something like a tab. Also a misplaced N or W or whatever will confuse the interpreter as to when a line ends and one starts (CR LF characters are allowed within a "line") and it will simply point to the FIXES header.

 

I'm willing to help you get through the learning curve, just quote part of my reply and I'll get a notification that you are directing a comment/question towards me.

 

Hi

 

Thanks to offer me your help, but i solved it already.

Your instruction of the problem really helped a lot, i went carefully through the whole file and found it then.

The problem was in one of the SID's, i forgot to insert FIX before a WPT and i had somewhere a typo.

Now everything is working fine  :)

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What I did find was the use of TRK in the APPROACHES section causes an error and the SIDS/STARS for that airport doesn't appear in the FMC.

 

The keyword TRK should work in either SIDS STARS or APPROACHES sections, perhaps the way you used it caused the problem?  You should not have a problem with number of declared fixes. As for arcs, the best we can do is put "pseudo waypoints" along the path about every 3 or more miles or 10 deg of arc to simulate the 'radius to fix' segment. The hard part is usually finding the center of the arc, which I use Compsys21 geodetic calculator as an invaluable tool because it understands paths on the earths' spheroid. This used to be free from the FAA but you can still find it out there via Google.

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The keyword TRK should work in either SIDS STARS or APPROACHES sections, perhaps the way you used it caused the problem? You should not have a problem with number of declared fixes. As for arcs, the best we can do is put "pseudo waypoints" along the path about every 3 or more miles or 10 deg of arc to simulate the 'radius to fix' segment. The hard part is usually finding the center of the arc, which I use Compsys21 geodetic calculator as an invaluable tool because it understands paths on the earths' spheroid. This used to be free from the FAA but you can still find it out there via Google.

 

Thanks Dan, your help is very much appreciated!

Regards,  Martin

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DAL521, on 04 Aug 2014 - 04:49 AM, said:

one of the SID's, i forgot to insert FIX before a WPT

Old topic I know, but was trying to create exactly the same thing: approaches for NZQN.

The painful part is inserting all the new fixes (QN775 etc.) - the lat lons needed to be worked out manually.

 

A few 'learnings' from editing the PMDG SID/STAR file for NZQN:

1) You must enter every FIX entered as part of a SID/STAR in the SID STAR file - it's not enough to have them in the waypoints file only.

2) In a STAR, it's invalid to put a TRK xxx degrees between waypoints: the FMC knows what the tracks are anyway (not 100% sure of this, but seemed to remove an error). Also, note the difference between HDG and TRK, and the use of OVERFLY to ensure a waypoint is actually passed over (next procedure eg. turn won't occur till this has happened)

3) For NZQN, the STAR mentions FL ranges eg. above 16000' and below 17000'. The way to code this is 'AT OR BELOW 10000 AT OR ABOVE 16000'

4) The default PMDG SID/STAR files for NZQN have 2 runways (05L and 05R, 23L and 23R). As NZQN has only one 05/23 runway, I took out 05L, 05R, 23L, 23R and replaced them with 05/23 throughout the SID STAR file, and in the airport file too.

5) The FIX lat/lons are in the format 'S 44 23.12345' ie. degrees, and minutes (including seconds) to 5 decimal points. This differs from some other PMDG files where the lat/lons are in the format 'S 44.234098' (degrees with minutes/seconds to 6 decimal points. I made a quick Excel file with macro functions to do this conversions which I found a great help.

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1) You must enter every FIX entered as part of a SID/STAR in the SID STAR file - it's not enough to have them in the waypoints file only.

You do not need to define a fix that is already in wpNavAID.txt file.  Use the keyword NAVAID instead of FIX

 

 

 


2) In a STAR, it's invalid to put a TRK xxx degrees between waypoints: the FMC knows what the tracks are anyway (not 100% sure of this, but seemed to remove an error). Also, note the difference between HDG and TRK, and the use of OVERFLY to ensure a waypoint is actually passed over (next procedure eg. turn won't occur till this has happened)

The FMC calculates the lateral path between waypoints, if they are far enough apart the track will be a great circle.  This is very important in polar navigation.  The opposite of OVERFLY is FLYBY which is always implied unless you specify OVERFLY.

 

 

 


5) The FIX lat/lons are in the format 'S 44 23.12345' ie. degrees, and minutes (including seconds) to 5 decimal points. This differs from some other PMDG files where the lat/lons are in the format 'S 44.234098' (degrees with minutes/seconds to 6 decimal points. I made a quick Excel file with macro functions to do this conversions which I found a great help.

 

The simulator only works with tenths of a second, so the additional precision is not necessary.  I use the geocalculator I obtained free from the FAA, COMPSYS21, which will calculate in the DDMMSS.SS format, number of decimal seconds is adjustable. Eliminates the need for conversions if you can just stick to the same format.  The calculator solves just about any geocalculation that I've run into.

 

I assume you have a copy of the "737NG How to make Terminal Procedures" by Terry Yingling.  This is a must have guide if you want to learn how to create sidstars, should be in the avsim library.

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On 1/23/2017 at 10:11 AM, downscc said:

 

 

You do not need to define a fix that is already in wpNavAID.txt file.  Use the keyword NAVAID instead of FIX

 

Old topic I know, but thanks downscc for that tip on using 'NAVAID' instead of 'FIX' in your SIDS/STARS. Saves a lot of hassle associated with getting lat/lons right, and in the right format. Thanks again.

Pete

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