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      Proper Problem Reporting for the TFDi Design 717   07/09/2017

      Folks, As the user count is increasing, it is becoming more of a task for us to stay on top of problem reports. We are also receiving an increasing amount of incomplete reports that we are unable to follow up on (which frustrates everyone, us included). On that note, we are going to be enforcing a stricter formal problem reporting system. There are a few main points that need to be addressed. ALL problem reports must be submitted via the Bugs and Suggestions system. Open discussion on the forums is fine, but our team simply cannot respond to every single comment (especially when the majority of doing so is asking for information the Bugs and Suggestions system already asks for). Incomplete reports will be ignored. This means reports like "my FPS is bad" will not be given weight. This isn't because we don't care. It is because a report like that does absolutely nothing for anyone - we can't fix it based on that. Please include EVERYTHING you can possibly think of regarding the problem and take as many steps as you can to isolate it. Prepar3D v4, despite what you have heard, can still be unstable. Yes, it is definitely possible to fly flights without issues. But it is still relatively new, as are most of the addons available for it. Please refrain from attacking us or other developers because of this. We have already had one scenario where a 717 CTD was resolved by an update to Prepar3D itself. This is likely not the only time that will be the case. You are still free to report the crashes, as it may help whoever the developers of the faulting code are solve the issue. Duplicate reports will be deleted/merged. For the sake of sanity for us trying to prioritize and evaluate issues, if we discover multiple reports of the same thing, we may merge/delete the duplicates. We strongly encourage you to search and see if your problem has been reported before. Thank you all in advance. This may seem overbearing, but this is the only way we are going to be able to stay on top and continue heading in the direction we, and the community, want.
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ZFWCG Calculation

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I am going to try explain how calculate the ZFWCG. It is something difficult because in the Flight Simulator there is some data that we can not get.

Ok, we must know that it is the 'DATUM' for calculate ZFWCG. The DATUM is an imaginary vertical reference plane or line chosen by the aircraft manufacturer from which all arms used for weight and balance computation are measured.

In the next image we have all necessary measures to calculate the ZFWCG:



Ok, We calculate ZFWCG with the next equation:

        ZFWCG = D - F*L/ZFW


D = Distance from Datum to Main Wheels, it would 2,3M + 17,6M = 19.9M

F= Net weight Nosewheel, this date we haven't it in Flight Simulator, suppose it is 7.000 kg

L= Distance from Nosewheel to Main wheels, it would 17,6M

ZFW= 42.000 kg

  ZFWCG = 19,9 - 7.000*17,6/42.000

  ZFWCG= 17 meters from Datum.

Ok, now we have to convert in % of MAC (Mean aerodynamic chord) for this we use another equation:



 ZFWCG% = CG from LEMAC * 100/MAC in meters


CG from LEMAC(Leading edge of the mean aerodynamic chord), it would 17M-15M = 2M

MAC would 22M - 15M = 7M

  ZFWCG% = 2*100/7

 ZFWCG% = 28,5%

For me this is very dificult to calculate in the Flight Simulator because some date as LEMAC and TEMAC distance and net weight nosewheel we haven't it.


Edited by Monty43

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