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kamoflarj

Modifying STAR

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I'm trying to modify a STAR for NZQN. The problem is whenever i enter the LAT/LON of a fix into the PMDG Nav files, it works in the game, but the fix isn't in the correct location. Now if i entered this fix from the PMDG FMC then it would be in the correct location. It uses the same coordinates. What am i missing here?

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I'm trying to modify a STAR for NZQN. The problem is whenever i enter the LAT/LON of a fix into the PMDG Nav files, it works in the game, but the fix isn't in the correct location. Now if i entered this fix from the PMDG FMC then it would be in the correct location. It uses the same coordinates. What am i missing here?

Wh yare you trying to modify a STAR? Do you use up to date AIRAC? 

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I meant that I'm adding RNP approach fixes after the last fix of the ELRUV1A STAR. The RNP Y navdata is not supplied for hobbyist sim use. I am using the MFD for checking where the fixes are.

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i think it would help if you share the code of the STAR you're working on. If it's from navigraph, i'm not sure if they'd like that, though...

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I meant that I'm adding RNP approach fixes after the last fix of the ELRUV1A STAR. The RNP Y navdata is not supplied for hobbyist sim use. I am using the MFD for checking where the fixes are.
Just out of interest why do they allow the use of RNP G (which I flew into NZQN during a vatsim event a few weeks back) and not the RNP Y?

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RNP approaches into NZQN are company specific, meaning you need special permission to use them. RNP approaches vary depending on the aircraft your company is using and what your aircrafts RNP is rated to. Also it is RNAV G, not RNP G

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kamoflarj, on 04 Jul 2014 - 09:00 AM, said:

RNP approaches into NZQN are company specific, meaning you need special permission to use them. RNP approaches vary depending on the aircraft your company is using and what your aircrafts RNP is rated to. Also it is RNAV G, not RNP G

Sorry you are quite correct, I just checked. Will chalk it up to answering too early in the morning. 

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It's ok. Easy mistake. The RNP approach into nzqn is far more interesting than the rnav g app. The only tricky part is modelling a DME arc, common to RNP. The pmdg737 doesn't do it. You have to make a virtual arc by creating lots of fixes about 0.5nm apart

MAUB, I think you are probably right. The other method used to create fixes was by using collocated DME fixes from the SH VOR. Obviously, if you know the exact coordinates, a bearing is not going to be anywhere near as accurate, given Magvar has to be taken into account for.

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Which RNP are you using, Air NZ, Jetstar or Qantas? Or are they all the same but approved per operator?

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The only tricky part is modelling a DME arc, common to RNP. The pmdg737 doesn't do it. You have to make a virtual arc by creating lots of fixes about 0.5nm apart

MAUB, I think you are probably right. The other method used to create fixes was by using collocated DME fixes from the SH VOR. Obviously, if you know the exact coordinates, a bearing is not going to be anywhere near as accurate, given Magvar has to be taken into account for.

 

Yes, the simple syntax used by PMDG doesn't do arcs or Radius to Fix (RF) as ARINC classifies them. However, every 0.5nm is overkill. I use no less than one per 10 deg of arc for most 10-14DME arcs. Finding the center of the arc is the tricky part, which I estimate by first finding the common point on two line segments extending 90 deg (orthongonally) from the straight line courses leading to and from the arc segment. Then several interations later using basic geometry I pick a point that looks good and is much better than required for the virtual arc. A must have for this exercise is a tool such as Compsys21 to do the geometry on the spheriod earth. The tool is no longer available from the FAA, where I got it years ago, but can still be found out there in the net... see Google. Good luck but warning, creating sidstars takes time to master but can become addictive to some types of personalities (like yours truly).

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I'm currently developing some software that will allow you to graphically create SID's, STAR's and Approaches. Its not intended to replace the bulk AIRAC data, but to fill in the holes such as different, missing or obsolete airports.

 

Its still in its early development stages. Keep up-to-date here: www.pollypot-software.org.uk

 

Best wishes

Steve

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Yes, the simple syntax used by PMDG doesn't do arcs or Radius to Fix (RF) as ARINC classifies them. However, every 0.5nm is overkill. I use no less than one per 10 deg of arc for most 10-14DME arcs. Finding the center of the arc is the tricky part, which I estimate by first finding the common point on two line segments extending 90 deg (orthongonally) from the straight line courses leading to and from the arc segment. Then several interations later using basic geometry I pick a point that looks good and is much better than required for the virtual arc. A must have for this exercise is a tool such as Compsys21 to do the geometry on the spheriod earth. The tool is no longer available from the FAA, where I got it years ago, but can still be found out there in the net... see Google. Good luck but warning, creating sidstars takes time to master but can become addictive to some types of personalities (like yours truly).

Thanks for that info, I'll have to have a go at it. I just downloaded Compsys21, what a great tool!

I'm currently developing some software that will allow you to graphically create SID's, STAR's and Approaches. Its not intended to replace the bulk AIRAC data, but to fill in the holes such as different, missing or obsolete airports.

 

Its still in its early development stages. Keep up-to-date here: www.pollypot-software.org.uk

 

Best wishes

Steve

 

 

That would be amazing if you can do that. I will most likely need it for decommissioned airports and editing the ever changing RNP approaches, here in New Zealand.

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That would be amazing if you can do that. I will most likely need it for decommissioned airports and editing the ever changing RNP approaches, here in New Zealand.

 

I kept about 60 sidstars up to date, every cycle, for several years and had to give up the full time hobby for some priority issues. I've looked at getting back into it now that I'm retired and have no priorities (well, one priority is beta testing for RSR) but haven't made the jump. However, I don't mind helping with specific issues. Also a must have document is "Making 737NG Procedures (5th Ed)" by Terry Yingling, which used to be in the AVSIM library.

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I still have a copy of that document.

 

BTW welcome back Dan and good to hear from you.

 

Dave

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There was a avsim user  (Msauce)  who made RNP approaches for  NZQN for the NGX, tied to navagraph nav data. It is in the Axsim lib.http://library.avsim.net/download.php?DLID=166014

 

And can be modified for current Airac I believe. John O'Duffy also helped. It works great, and a lot of work went into it.

*******************************************************************************************************

 

From the readme:

Intro:

This is a terminal procedures package for Queenstown, New Zealand (NZQN). This package includes the RNAV-RNP procedures as well as the navaid based standard instrument departures and approaches to get you in and out of this picturesque and challenging airport. They are designed for use with the amazing Boeing 737-NGX from PMDG and with the stunning New Zealand South Island region scenery from FTX (accurate guidance with terrain clearance has
only been verified with this pay-ware scenery).
 

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If you own Flight Sim Commander and bring up NZQN all the radius points for the RNP-Y's are there for you.  They are designated 'RQNnnn')

As Dan indicated (nice to see you back Dan) this is the hardest part in constructing RNP's for PMDG.  The rest is just plain tedious!!!

 

I have given the RNP-Y's a shot for both RWY's.

You can download them at http://www.vapap.com/downloads/as-pmdg

If you don't want all the other procedures in the download, just install to a folder outside of FSX  and copy the NZQN.txt file into your 'sidstars' folder.

 

Flying it, the NGX ND is horribly busy with all the user waypoints to keep the kite in the arc.  Must keep the speed in hand for them to work

Could be some overkill as Dan would say.  Havn't had the time to go back and refine.

 

For those interested the RNP's for NZAA are included in the above download.

 

Cheers

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I believe we spoke via email, jockos. For anyone wanting good NZQN RNP procedures, use the ones linked above. I'm still interested in creating my own STAR though, the way Dan described creating arcs intrigues me :)

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