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mikkel

Reduced (Flex) Thrust Calculation - CONT.

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Short question, where can I find a chart to correctly enter a reduced assumed takeoff temperature?Thank you,Mikkel

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Short question, where can I find a chart to correctly enter a reduced assumed takeoff temperature?Thank you,Mikkel
If you where quick you could of got it here about a week ago but it was deleted for obvious reasons. Boeing are not allowed to release data on the MD11 to the general public, this is likely due the MD lawyers flexing there muscles when Boeing bought them out, of course that is only pure speculation but it's strange that Boeing have no issues releasing data on there own flagship Aircraft.I have managed to get some data, but I'm confused as to why the max FLEX temp I see is 50c when the aircraft let's me enter up to 70c? Also if the pressure is less then 1000mb FLEX is not authorized. I've been flying around Europe for the past two weeks and the pressure is always below 1000mb. Does anyone know why this limitation is in place?Rob

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I would assume its because the decrease in performance an aircraft gets as the pressure falls. Just as the engine performance decreases as the flex temp rises. There has to be a point where the aircraft has to say "thats enough already".

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I have managed to get some data, but I'm confused as to why the max FLEX temp I see is 50c when the aircraft let's me enter up to 70c?
Just because the FMC will accept it, doesn't mean you can legally do it. Different regulations will apply to different airplanes. It may well be a case where the aircraft can do a FLEX70 takeoff, but that airline only bought performance date for temps up to FLEX 50.

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Take a look at this Forum, it is German, but they discuss the same problem and got an good solution even for non german speaking. !! Deleted LINK to an German Flightsim Forum !!RegardsFrank

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Now how long till this thread gets deleted......... Frank it's Illegal to post this on here, remove it!Rob

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Now how long till this thread gets deleted......... Frank it's Illegal to post this on here, remove it!Rob
I don't understand why it is illegal, if it is so, every post with an Link to another source of interrests must then be illegal ! I can see several links to different locations here in the Forum, so you have to delete every of this posts.But OK, I will not get in trouble, so I will remove the link again, but think over the lines I worote above.Regards Frank

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I don't understand why it is illegal, if it is so, every post with an Link to another source of interrests must then be illegal ! I can see several links to different locations here in the Forum, so you have to delete every of this posts.But OK, I will not get in trouble, so I will remove the link again, but think over the lines I worote above.Regards Frank
Are other posts linking to websites with illegal content on the same page? I dont think so. The link you gave is blatent and required no hunting around for info. If I had it my way I would share all the data I have with my fellow simmers but not on this forum. The bottom line is Avsim let us use this forum for free, that does not give us the freedom to post links to illegal content.If anything suggest pilots to email you but dont make it so obvious.Rob

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Now how long till this thread gets deleted......... Frank it's Illegal to post this on here, remove it!Rob
You can't go on like this. He posted a link to another thread with a discussion on this issue. As a part of the free world, I find your attitude quite provoking. Sorry for my harsh words, but authoritarian thinking is something I don't accept, and therefore I voice my opinion, even though I know I have no authority on this forum... :(

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If you where quick you could of got it here about a week ago but it was deleted for obvious reasons. Boeing are not allowed to release data on the MD11 to the general public, this is likely due the MD lawyers flexing there muscles when Boeing bought them out, of course that is only pure speculation but it's strange that Boeing have no issues releasing data on there own flagship Aircraft.I have managed to get some data, but I'm confused as to why the max FLEX temp I see is 50c when the aircraft let's me enter up to 70c? Also if the pressure is less then 1000mb FLEX is not authorized. I've been flying around Europe for the past two weeks and the pressure is always below 1000mb. Does anyone know why this limitation is in place?Rob
Hi Rob, the reason that there is a limitation of QNH 1000 is probably because of fixed margins being used for QNH correction. If the QNH falls below 1000 there is no margin for the Performance Limited Take off Weight so a Full Thrust take off has to be made, and the pilots have to calculate the QNH correction. For every Hectopascal below 1013 you'll get a penalty of around 250-300kg. So the fixed margin is probably around 4000 kgs for a Flex Take off in this case.

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You can't go on like this. He posted a link to another thread with a discussion on this issue. As a part of the free world, I find your attitude quite provoking. Sorry for my harsh words, but authoritarian thinking is something I don't accept, and therefore I voice my opinion, even though I know I have no authority on this forum... :(
Sir did you have a look at the link that was posted? Yes there was a discussion, but there was also pages of scanned Swiss Air performance data, this is illegal no matter how you try to look at it.Personally I don't care, and I find it quite annoying that we don't have free access to this data as we don't plan on selling it to Airbus, the Russians, Iran, Aliens or whoever.If we where chatting on some random blog or some little website I wouldn't say a thing, but on Avsim, one of the largest public simulation forums I 'personally' dont think it's right for people to post links to copyrighted material.Rob

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I voiced my opinion, and I'm finished with this issue.I found the charts you mentioned, actually from a link on avsim, but isn't right that Swiss Air is out of business? Do we know that this material is now copyrighted to their new owners? Do they even use the MD11 any more?

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Hey Mikkel, I think you misunderstood, the FLEX data belongs to Boeing, it has nothing to do with the sale of Aircraft. (this thread is getting pointless and starting to take up bandwidth)Rob
Agree, but I'm sure there are people out there interested in the legal dealings of aircraft sales...By the way (when we are talking about bandwith), did you know that by 2020, the server industry will pollute as much as the airline industry? We better start saving that bandwith, not only for our own sake, but for the enviroment as well!

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