duckbilled

Strategies for reconciling the discrepancies between FSX nav data and FMC nav data

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Hi,

After a long time simming, I finally broke down and purchased a few PMDG aircraft. I always thought I didn't have time to learn a complex aircraft, and I was wrong. The learning curve isn't that bad, and I am really enjoying the NGX and the 777. I should have listened to everyone on this forum a few years ago. I am now using FSX and ProATCX for planning and ATC.

Anyway, one issue I am have trouble with is dealing with the discrepancies between nav data and what is actually in the sim. I almost always fry to/from add airports and I intentionally keep a few out of date airports installed. Either way, I can't think of a way to make sure the FMC matches the sim. Of course, this is based on the assumption that the aircraft will not follow a STAR listed in the FMC if the components are not included in the scenery. Is this assumption correct?

If this assumption is correct, how does everyone get around the issue of STARS being loaded into the FMC that don't actually exist in the scenery?

Thanks.

 

 

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STAR is a procedure, it cannot be included in scenery. You probably wanted to say navaids. There are 2 things to do.

1. To keep FMC data updated https://www.navigraph.com/ or http://www.aerosoft.com/en/fsxp3d/flight-simulator-2004/tools-missions/1750/navdatapro-one-year-subscription-13-datasets . They have navdata(monthly)for all popular addon aicrafts and simulators. 

To keep simulator data updated(magnetic variations, navaids etc) https://www.aero.sors.fr/

 

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can you be a little more specific about which airport or what isn't matching? generally a lot of the waypoints in a star are just coordinate definitions, so they aren't really in the scenery per se. these should be handled fine without any trouble.

as you have noticed, however, some of them may include VOR or other navaids that could change, which is where some trouble arises. in practice it seems to me the fmc treats these coordinates generally the same way as regular waypoints though, so the discrepancies you see may end up being pretty minor if it is just a point in the star you are flying over in LNAV. beyond that, i know the pmdg planes can also override the heading on an ILS for example with whatever is in the sim instead of what the fmc says (this is a selectable option i believe)

obviously stuff that requires tuning with frequency that has changed, may require you to manually tune the frequency yourself, in that case... look at the airport in the fsx map to get the proper freqs and override what the fmc thought it was..

good luck,

-cheers,andy crosby

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Of course, this is based on the assumption that the aircraft will not follow a STAR listed in the FMC if the components are not included in the scenery. Is this assumption correct?

I am surprised no one has answered this specific question.  Nothing could be further from the truth.  I use the PMDG B737 and B747 for FS2004, which is far more outdated than FSX and I follow Arrival Procedures stored in the FMC all the time.  It will even let you fly to an airport that didn't exist when FS2004 or FSX was released and is not in the default database.

Best example I can give is Seattle Tacoma Int'l.  The third runway wasn't built yet when FS2004 and FSX were released, yet your PMDG B777 will still "land" on 16R in the grass.  In the sim 16R will be the same runway your FMC is calling 16C, which doesn't exist in the sim default runways, yet your PMDG will gracefully make an approach to the sim 16R thinking it is really 16C.

Randy

 

 

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4 hours ago, duckbilled said:

 Of course, this is based on the assumption that the aircraft will not follow a STAR listed in the FMC if the components are not included in the scenery. Is this assumption correct?

If this assumption is correct, how does everyone get around the issue of STARS being loaded into the FMC that don't actually exist in the scenery?

Thanks.

 

 

Jeff,

The NGX and T7 use their own navdata and it doesn't matter what navdata is in FSX. It wouldn't even matter if FSX had any navdata at all except for the ils course and frequencies for runway because the PMDG planes operate independently from the data in FSX.

So for instance, you grab a route off flightaware and input it into the FMC it will follow the whole route including the SID and STAR despite the data the FSX has.

Its pretty simple, no need to over think it or make more complicated that it is.

If you are going to start doing some serious PMDG flying, you might want to get PFPX for route planning and fuel planning. Plus you can export the flight plan as a company route and then easily load it into the plane via the FMC.

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The pmdg planes will even change the heading on the crs if it's not the updated heading. you can dial the wrong heading on the crs and the system will change to it to right one before landing. Example, tncm-mpto in the Caribbean. FSX heading (for mpto/ rw3) is 30 degrees. Real heading 33 degrees, with navigraph. I set Ngx 30 degrees and it corrected itself on the crs. No problem landing...

Cheers.

john

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Thanks all. I am totally clear on this now. I had a feeling that this was a silly question. I guess the reason for my confusion is if you open up most ADE files you do see waypoints and other navaids. If you delete those from the ADE, or you import a AFX file into ADE without adding in the default approaches and naivaids, you will not have any approach data in the default GPS. In ADE, you can also create approaches. Based on that, I incorrectly assumed that the FMC data were basically referencing what should be contained in a fully up to date sim.

I've been thinking about getting a Navigraph subscription, so this seals the deal. Everything should be OK if I update the FMC data and the ProATCX data to the same cycles.

 

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Aircraft can either rely on data provided as part of the aircraft addon, or on whatever data is in FSX.   Ideally, they match 100%.  The problem is, many simmers want to use "real world" data, and they constantly update the aircraft addon data.  Thus there is a delta between the two sets of data.  It is feasible to update FSX or P3D to current "real world", but the way the data are structured as part of the scenery database, it isn't as easy as you would want.  So you have to decide on what trade-offs you are willing to accept.

The first priority probably should be the visual scenery, since flying to non-existing runways and taxiways kind of kills the buzz.  That means getting addon airports where you are going to fly.

One big advantage that didn't exist when FSX was released is now most air navigation is based on GPS lat/long positioning instead of the old "rho-theta" that was harder to convert into FSX-compatible data.

scott s.

.

 

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