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Guest CS-THV

Please help (744 Manual)

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Guest CS-THV

Hi there!I can't understand something regarding the takeoff Vspeeds tables, in the 744 manual (for example, page 44). What is "Temperature - Altitude Region"? Because I can't find temperatures nor altitudes, only letters (A to L). Can you please explain it to me?Also, are there any Reduced Thrust (FLEX) takeoff tables in the manual? I couldn't find them.Thanks! :)

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Guest CS-THV

Aha! I found some info on the first issue. But still can't find info on the Reduced Thrust (Assumed Temperature) derated takeoff.

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Joao-The tables are there to help you with planning, but since the FMC provides you with all of the various reduced thrust configurations, I felt it was not necessary to type them for you. ;-)


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PLEASE NOTE THAT PMDG HAS DEPARTED AVSIM

You can find us at:  http://forum.pmdg.com

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Guest glide

Hi Rob i know that the fmc has derated take off options but how do you know when you can use derated T/O or reduced thrust settings and assumed temps as opposed to when you cannot are there any tables that can help you decide and to what level?thanks Kav

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I think it said they use a derated takeoff all the time, unless they can't...too short a runway...too heavy, weather etc

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Guest glide

Yes but the max TOW are the same for the derated & max thrust tablesso it cannot be a weight thingand also how do you determine what level of derate you should use thare must be some formula / calculation combining a few variable factors like runway length v weight to work out exactly what derated-5% -15% etc to use can anyone(744 Poliots) shed some light on this thanksKav

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Guest CS-THV

Well, one thing I am sure of: you can't make a derated takeoff with a contaminated runway (standing water, snow, etc.).

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>thare must be some formula / calculation combining a few>variable factors like runway length v weight to work out>exactly what deratedLike I once said pilot have customized tables for every runway they fly out to tell them how to compute derated takeoff values (The ITVV video shows such a calculation being done for runway 27R at Heathrow). Maybe some real 744 pilot will provide us such tables for a few 'typical' airports/runways that we will be able to apply. Michael J.WinXP-Home SP2,AMD64 3500+,Abit AV8,Radeon X800Pro,36GB Raptor,1GB PC3200,Audigy 2http://www.precisionmanuals.com/images/forum/747400.jpghttp://www.hifisim.com/images/asv_beta_member.jpg

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Guest neil_b

I'd recommend you take a look at www.tomaflex.netThe site says that it plans to support the PMDG744, which hopefully it will. Its cheap and will allow you to get an assumped temperature takeoff.

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Guest CS-THV

Well, they also planned to support SSW A310 and LVL-D 767 for MONTHS now and it hasn't been updated. Also, the database runway information of the program is very old.

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Guest glide

Thanks very interesting site kav

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>Also, the database>runway information of the program is very old.Not sure how relevant this would be. They clearly state that their calculations would reflect what you would 'feel' in FS, and we know that FS for example doesn't support sloped runways so whether they are close to real-life database may be unimportant - it is rather important that they stay close to what's in MSFS.Michael J.WinXP-Home SP2,AMD64 3500+,Abit AV8,Radeon X800Pro,36GB Raptor,1GB PC3200,Audigy 2http://www.precisionmanuals.com/images/forum/747400.jpghttp://www.hifisim.com/images/asv_beta_member.jpg

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Guest neil_b

>Well, they also planned to support SSW A310 and LVL-D 767 for>MONTHS now and it hasn't been updated. Also, the database>runway information of the program is very old.Chillax dude.1) As someone just said, all that matters is the runway information matches FS's.2) Its the only program that I know of that offers such calculations. So unless you are willing to write your own I'd suggest you hope they will update it.

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Also I am not even sure if this tool is so sophisticated as to account for obstacles. One of the main reasons the same runway may have very different derate/assumed temperature computations as opposed to its reciprocal are obstacles. If they are terrain obstacles then perhasp this tool would have a chance since with an accurate terrain mesh you could 'experience' it in FS9. But very often these are man-made obstacles like buildings or radio towers. An updated information presumly would reflect any new/removed man-made obstacles that would impact such take-off calculations. But again, I doubt this program is so clever to account for things like that.Michael J.

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Guest bernarte

Still haven't heard anything about what the "A thru L "culumns mean

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