jordanal

TopCat + PFPX + 737NGX / Weights (How To)

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Awesome! Thank you for these clear instructions! Just finished setting everything up and it is spot on!

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I do appreciate all of this information.  I am a GA guy at heart but I do like the change of pace and a differnet type of complexity when it comes to big tin flying.   I finally broke down and picked up PFPX last night.  Great planning tool.   I need to keep on reading and keep on investigating to fully understand the planning concepts. 

 

The one thing that has always bugged me is trying to determine if my aircraft profiles are correct "enough" to provide somewhat accurate fuel burn predictions.  It's always felt like a black box mystery to me.    A year or two back when I first picked up the NGX, I changed some weight values (from a thread found here in AVSIM) but as I recall, all of the configuration information was in one large .txt file, not separate aircraft .txt as I see in Topcat Configuration folder. I can't seem to find that file now.   Does any one know which file I am talking about?  Maybe I am out to lunch.

 

Any way - the questions are or at least verification

 

1) TopCat .acft and the configuration .txt files.  Is it that the .acft calcualtes the v speed and the .txt handles the derate and fuel burn?

 

2) When I make a new plane profile in TopCat:

- Should I use the B737-800" For type selection with the PMDG 737-800 configuration?

- Are the engines correct model CFM56-7B23 or is there something I need to change there also?

 

I will follow the steps listed at the front of this thread and download the .txt configuration files.  Thanks for those.   I am concerened that what ever I changed 1.5 years ago will be lingering around somewhere when I changed some weight values.  Just not sure where that was and not sure they will be nulified when I use these .txt configs from this thread and generate new aircrafts.

 

I need to get a grip on how this all works so I can do it correctly for the T7 as well. 

 

Benjamin

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Hello Jordanal

 

I seem to have this working with all the correct weights thanks for the instructions, I cant seem to get the topcat v speeds and N1 settings to match the 737 NGX FMC, is this normal or should they exactly match for full power and any derates, thanks

 

Wayne

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I don't think mine ever matched exactly, but they weren't extremely different either.  I always trust the FMC in the end, it has my virtual pilot life in it's hands, LOL... 

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Benjamin,

 

 


1) TopCat .acft and the configuration .txt files. Is it that the .acft calcualtes the v speed and the .txt handles the derate and fuel burn?

 

Pretty much...  I think the .acrft files ('types' in the GUI), are hardcoded performance v-speed related.  It's these files that we wait for to be updated or newly released from Christian.  They are the files that accurately model an aircraft.  My text files on the first page are basically all the weight values and so forth that directly affect derates and so on.  These files are created and changed when you create a new aircraft (based on a 'Type') in the TopCat GUI

 

 

 


2) When I make a new plane profile in TopCat:

- Should I use the B737-800" For type selection with the PMDG 737-800 configuration?

- Are the engines correct model CFM56-7B23 or is there something I need to change there also?

 

- Yes, Use the B738 'Type' for selecting both the 737-800 and -900's.  Maybe someday we'll get a real B739 aircraft 'Type' from Christian to make it more accurate.

- I'm not exactly sure if the CFM56's are the 'most' accurate engine for any particular model, but it seems to be the only engine available in the drop-down, so there's not much choice.

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The biggest headache using TopCat and PFPX (prior to launching FS) is determining if the desired 737NGX variant is a single-class or mixed-class configuration. I personally like realistic livery.ini configs and keep them as originally created. To determine the respective livery.ini file before firing up FS, I use a free program (from the AVSIM library, I think) called AIRCRAFTER. I load it up and drill down to my desired PMDG 737 variant I wish to use for the flight. I then have AIRCRAFTER open the texture folder for the chosen livery and I inspect the livery.ini file. Near the bottom of the livery.ini file, there is a line similar to 'singleconfiguration=1', which defines a single-class variant, or if set to zero, indicates a mixed-class variant. This is irrespective of the fact that you could simply change the class (single or mixed) once you load up the livery in a FS session, and change it in the FMC Aircraft options to match your PFPX and TopCat weight calculations (number of seats).

 

 

BTW, the above paragraph from my OP has been superseded by the new PMDG OPS Center, which functions for the NGX as well.  You can not only view the current Cabin Class layout (one or two classes) directly in the OPS center, but you can change and save it to the livery.ini here as well, before firing up FS.

 

 

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Where do I get the PMDG Op Center?  I have the 737NGX but not the T7.  I can not find it anywhere.

 

Lynn

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Where do I get the PMDG Op Center? I have the 737NGX but not the T7. I can not find it anywhere.

 

For the moment, it only comes with the T7 as part of the install.  They'll make it separately available for the other products as soon as they can.

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Thanks for this info!  I just purchased PFPX and was looking for info on weights and such and ran across a reference to this post.  Just what I needed.  I'm not using Topcat (using the spreadsheet that's floating around here instead), but it sounds like I can take all those values to at least get PFPX working accurately.

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Am I reading the first page right?  The -900 has less cargo capacity than the 800?  11,100 pounds vs. 16,400?  I realized I've been running around with the default 14,400 (or I got that from somewhere) and it lets me put that in the -900 but obviously I need to change that then.

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the -900 weights are the same as the -800s except for the DOW and cargo, is that correct? also, PFPX has 2 templates for -900. one says template name "PMDG 737-900W NGX Winglets" and type "Boeing 737-900ERW". the other says name "PMDG 737-900W NGX Winglets" type "Boeing 737-800ERW". witch do I use?

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Use the 900W. PMDG did not release an ER variant.

Ok here's what I'm looking at, they both sat 900W.

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Many thanks for taking the time to post this information. I have had TOPCAT for about year and enjoy using it. I finaly got round to getting PFPX the other day and this info that is posted here is the first thing I did a search for. I was really pleased to find it here. I set it all up today and did a few tests and it works really well.

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Search for b737ng dispatch sheet on avsim. Its an excel file thats going to do all the performance calculations you need. It will work for 6,7,8, and 900s in any available configuration. It will calculate everything from fuel consumption to weights to vspeed to center of gravity to derates and a lot more.

 

Cheers

Lasse

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good job!!! Thanks, but it's possible read guide with the KG? Thanks :)

 

 

help me, please...

 

I am also  not sure what You exactly mean with Your question - but - if You want to have the weights in KG rather than LBS, just enter the numbers in LBS (as provided here in this thread) and then go ...

... to the "PFPX options menu" for "weights/units" and select KG there.

The same procedure applies if using these numbers with "TOPCAT".

Enter them all as provided here in LBS and then convert them via the "options menu" for "weights/units" into KG as well.

You should now have all the weights converted nicely from LBS to KG and can use them for Your flightplaning.

Hope this helps.

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