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H4wkeye

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So, if you use for example an Airbus A321 along with FSPassengers, how would one calculate what's the CG to enter it into the FMC? The CG that FSPassengers shows is WAY off for the load.

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You use whatever CG the payload editor gives you otherwise you will end up using the wrong t/o trim and MCDU calculations will be wrong. What CG is fspax giving you? Your options are, stick with the CG or find a better custom loader for fspax or even better use a realistic payload editor like TOPCATRegards


Rob Prest

 

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For some less advanced planes you can also look at the fuel and load screen from FSX menu. It should give you a rough estimate of your current CG


Johan Pettersen

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For the Simaddons customers there's a small and free tweak available, showing a more detailed CG in the default FSX payload screen. Pretty neat stuff.It gives you this.63519327.jpgBut maybe a talented painter can do the same when not being a Simaddons customer and simply exchange the default diagram in FSX.

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I think you can also disable the load part of the configuration in FSPax.

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Guest jahman

In the RW as a backup,can't the FMC automatically calculate weights and CG via the hydraulic pressure (and/or extension) in the shock-abosber in each landing gear strut? Cheers, - jahman.

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I simply ask my Multi Crew Experience first officer things like "What's the Zero Fuel Weight?" and "What's the CG?" and she has the answers right for me. I can ask such things repeatedly while FS Captain is loading my pax and cargo and the values change as the load "settles." cool.png

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You use whatever CG the payload editor gives you otherwise you will end up using the wrong t/o trim and MCDU calculations will be wrong. What CG is fspax giving you? Your options are, stick with the CG or find a better custom loader for fspax or even better use a realistic payload editor like TOPCAT Regards
I will try that thank you. It's giving me between 31 and 35% of CG, depending on the amount of PAX and the fuel. That is on the Airbus A320.
In the RW as a backup,can't the FMC automatically calculate weights and CG via the hydraulic pressure (and/or extension) in the shock-abosber in each landing gear strut? Cheers, - jahman.
In a real Airbus, on your EFIS I believe, under your GW, you also see GWCG % updated in real time I think, but I don't think that's the case here.
I simply ask my Multi Crew Experience first officer things like "What's the Zero Fuel Weight?" and "What's the CG?" and she has the answers right for me. I can ask such things repeatedly while FS Captain is loading my pax and cargo and the values change as the load "settles." cool.png
I don't have MCE.. Hm maybe I should get that. Does it work with FSPax?

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I don't have MCE.. Hm maybe I should get that. Does it work with FSPax?
I don't see why not, but I don't use FSPax so I can't say for certain. MCE is a "Swiss Army Knife" type of utility (that's made in the UK actually, so forget about the "Swiss" aspect) which gives you a speech-recognition commandable first officer that can handle many functions such as "set heading 123" or "arm approach hold"; run verbal checklists; handle FSX/Radar Contact ATC; tell you when you're drifting off of heading; etc. It can also check certain aircraft and simulation values such as ZFW, CG, transition altitude, v-speeds, your local weather, etc. The latest version of MCE supports "Vox Scripts" which are simple command scripts that can automate procedures. (I've a procedure script that can make my aircraft cold-and-dark for example.) So you need a good microphone and an English-capable Windows speech recognition rig. (I'm still on Vista 64, fwiw.) MCE talks back using your Text-To-Speech engine, so having a good voice there would be a plus. I've used the default Microsoft Anna which is workable, but there are much better addon voices (IVONA, Cepstral, AT&T) available. MCE has a time-limited full function trial mode so if it sounds interesting, install and try to see.

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I don't see why not, but I don't use FSPax so I can't say for certain. MCE is a "Swiss Army Knife" type of utility (that's made in the UK actually, so forget about the "Swiss" aspect) which gives you a speech-recognition commandable first officer that can handle many functions such as "set heading 123" or "arm approach hold"; run verbal checklists; handle FSX/Radar Contact ATC; tell you when you're drifting off of heading; etc. It can also check certain aircraft and simulation values such as ZFW, CG, transition altitude, v-speeds, your local weather, etc. The latest version of MCE supports "Vox Scripts" which are simple command scripts that can automate procedures. (I've a procedure script that can make my aircraft cold-and-dark for example.) So you need a good microphone and an English-capable Windows speech recognition rig. (I'm still on Vista 64, fwiw.) MCE talks back using your Text-To-Speech engine, so having a good voice there would be a plus. I've used the default Microsoft Anna which is workable, but there are much better addon voices (IVONA, Cepstral, AT&T) available. MCE has a time-limited full function trial mode so if it sounds interesting, install and try to see.
I downloaded the trial, I'll check it out later. smile.png Oh and on funny side note I guess, I own a real Swiss Army Knife, that I got in Switzerland just recently. What a great tool, it's really sharp and made of stainless steel.

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Alright so I've been experimenting a bit and after a long time of doing stuff, I think I know what's the best. Either use the values given by FSPax and enter their CG value and all, or disable the FSPax payload and fuel completely and then use an external software such as TOPCAT to add fuel and weight to the plane (And use it's CG values). I'm gonna test it out I guess and see how it works.

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Just wanted to point out that on the real aircraft you have to enter the GW/CG. The MCDU does not calculate this for the crew. REgards


Rob Prest

 

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Just wanted to point out that on the real aircraft you have to enter the GW/CG. The MCDU does not calculate this for the crew. REgards
How do they calculate the CG? Do they have some papers with info or are they using a tool?

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The dispatcher provides the final load figure, some airlines have it uplinked via ACARS directly to the FMC.Regards


Rob Prest

 

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It appears that my experiments completely broke the plane now... sad.png It won't hold altitude anymore. The AP is on and it follows the navigation and speed properly, trimming is good too, but it just refuses to follow the Vnav profile. I set alt to 9000 and it just goes through it and keeps climbing and climbing... I guess it wants to go to the Moon or something.Edit: So it appears that for whatever reason, the autopilot set the altitutde to 50 000 feet, even though I've put 9000 and pushed the knob. Sigh, guess I'll reinstall.Edit2: Actually, scratch that, I'll just reinstall the whole FSX and install only the essential mods I use. That's when it worked the best.

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