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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.

How to calculate the FLEX TEMP? (Tutorial)

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Hello friends, 

First of all thanks to the development team for this  amazing aircraft. My name is Jose Antonio Montiel from Málaga I am 24 years old, I am aircraft mechanic in the real life and I have worked a few in the B717-200, at present I work in the B737. I would like to share my little knowledge with you.

In the B717 there are two types of reduced thrust:

* Limit thrust: is a % lower of thrust for the total thrust in the current OAT or FLEX/Assume Temperature. TO1 -10% TO2 -20% .

*FLEX TEMP: is a temperature that we put in the FMS so that the FADEC misleads the engine to assume more temperature than it actually is and thus obtain a lower thrust.

Ok, how do we calculate our FLEX TEMP for current conditions?

We have:

* T/O Weight 53.000 Kgs

* Airport Elevation 1.000ft

* RWY Lenght 2.200 Meters and dry

* Winds 10 HW

* Slope 0%

* OAT 20ºC

* Flaps configuration 13º

* Type Engine BR700-715C1-30

So that we can know our FLEX TEMP we have to calculate our maximum temperature that we can assume with our take off weight, how? Ok we go to de FCOM performance dispach and choose the table for our conditions:

The first step is RWY Lenght corrections:



Is 2.290 Meters.

And second stet calculate our Max FLEX TEMP with T/O Weight 53.000 kgs



FLEX TEMP is 40ºC, 45ºC It could not be because the Maximum take off weight(performance, not structural) is less than we have 51.300 kgs and the same for Climb Limit weight (performance).



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Thanks for the tutorial!

However, where can one acquire the performance tables illustrated in your post? The TFDi does not seem to include these.

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On 29/8/2017 at 10:06 AM, raunzos said:

Thanks for the tutorial!

However, where can one acquire the performance tables illustrated in your post? The TFDi does not seem to include these.

Hello raunzos,

The table are from Flight Crew Operation Manual (Performance chapter) is real documentation. You can get here http://www.mycockpit.org/forums/downloads.php?do=cat&id=6&page=3


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