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flusie01

PMDG 737 and VSpeeds

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Hello again,sorry for the late answer, but i have checked "Enable email notification of replies?" , but become no eMail .. hmm.Ok, the question about the VSpeeds is also why are the Speeds in the same outside situation and the same procedure i taken to programm the FMC and load the airplane, in the 737-600 the same and in the 737-800 so very different ??Load the 737-600 and crosscheck the FMC and TopCat Speeds ---- are the sameLoad the 737-800 and crosscheck the FMC and TopCat Speeds ---- very different ( not only 1 or 2 knots )I have taken the absolutely same procedure for both airplane setups !!You can also call me via icq : 258167793ThanksMatthias
Hi Matthias,I will be away for about six weeks so that you are going to have to try and get your answers from someone else.One final thought is that 600 series was produced in 1994 ,as is common in the real world adjustments and improvments have taken place.and rather than update the manual the PMDG team carried on producing new models etc.Norman Bowman

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Hello,i have written to the PMDG Support and hope i become a positive response.If here is another user and can help me...plese contact me.ThanksMatthias

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Ok, I tested this for all 4 versions of the 737NG30000 lbs of payload10000 lbs of fuel5

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Hello,thanks for your Help, in the FMC i have the same Values with your Payload and Fuel.But the Question was the difference between the Values from the FMC and the Manual !!Look here :LBSFMC PERF INIT PAGEPMDG ManualFMCTOPCATACPayloadFuelGrossWeightZFWV1VrV2V1VrV2V1VrV2737-6003000013300123500110,2118119129118119129Not avail in TopCat737-7002100016000120000104,1116119129116119129123124128737-8004379112000147000135,1143145154130140149140141147737-9004350012000150000138,2143145155143145155Not avail in TopCatLook at the Bold red marked Speeds !!!FMC VSpeeds from the 736, 737 and 739 are absolutely the same as in the Manual !!But the FMC VSpeeds fromn the ( mostly flown ) 738 are absolutely different and not only 1 or 2 Knots !! That was nearly 10 knots difference !!!Are that Differneces the same on your System ?Why we have differences with the 738 ??Matthias Ps.: I have added a Picture of the Excel Table .. lost the format in the Post

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Just a small piece of information, in case you are not aware of it...V1 is dependent on runway length in general, so for a given TOW and flap setting, V1 is not going to be the same for a 7000ft or 10000ft runway, given that V1 is the maximum abort takeoff speed ( I know some call it the decision speed, but that term is misleading, since the decision to abort cannot be made after it...). The less tarmac you have for your takeoff run, the slower your V1 will be... Vr and V2 are not runway dependent as far as I am aware.I believe TopCat takes runway length into account when calculating this stuff... the manuals will only give basic data on a standard runway length (maybe 10Kft?)Andrew

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Hello,yes i know, V1 is the Speed, when i slower as V1 i can STOP the Take Of run.But as your write

Vr and V2 are not runway dependent as far as I am aware.
Vr and V2 are also as V1 very different between the Values from the FMC and the Manual!!And also for a Runway length as in EDDP ( more then 11000 ft ) are the Runway length no theme for the calculated V1 !Also i have taken the ICAO Wheater ( 15

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I just use the values calculated by the FMS. I sometimes reduce V1, particularly if the runway is shorter, but I leave Vr and V2 at their respective settings. At lower temps on longer runways, I consider assumed temperatures and de-rates, but without actual guidelines, it is difficult to calculate the required assumed temps... this is where TOPCAT can come in, but I don't have that...The FMS Vr/V2 have always worked thus far.Andrew

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