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Guest tompeel

747F low and slow

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Guest tompeel

I sometimes get stuck in a situation with the 74F too low and too slow. Right now it's at ZFW 540,000 and 96,000 lb fuel on board, chugging along with thrust limit on CON with the nose way up at about M.73 and FL320, the FMC says it should be up at FL370 and M.84. Oops, as I watch it's drifted down to FL300 and M.70 - -how do I get this beast back on target? I'd already FLCH'd it down from FL330 to FL310 to pick up speed, still too slow.Now it's down to FL270 with N1 at 109.3 and M.70, where are those parachutes? Just did a kamikaze A/P off nose down to FL250, re-engage A/P, now it's again struggling at M.72 and FL270. I've now taken out the A/P and at full thrust N1 about 111.3% it only just keeps moving. FMC says optimals are FL364 at M.840Is this normal?

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On the next flight try changing the CI ( cost index ) to 80.Or you could use speed interviene to speed up and bring the nose of the aircraft down.


Kevin Hester,

 

Indianapolis, Indiana

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Guest Raphouille

Hi, You may also check that the Outside Air Temperature is normal for your altitude.It's hard to fly high and fast when it's too hot.At FL320, the temperature should be in a range of -35

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Guest tompeel

Thanks for those tips. I'm using a CI of 60, and Active Sky flying over S. Asia. If it is too warm, what is the solution, simply fly lower?Can this happen in RealWorld?Tom

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I believe it can happen in the real world and the best thing to do would be to fly higher. The higher the altitude, the lower the SAT. Check your VNAV cruise page of the FMC and step climb to your optimal altitude if you need to. If your pitch is to high it could be weather related or speed related.


Kevin Hester,

 

Indianapolis, Indiana

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I've had to stop flying with my Virtual Airline over South Asia this summer. Not sure whats going on but this has been a major issue that I have only seen over the past four months. The CRZ temps are very high and the perfomance is very poor. I guess whatever stations are feeding Active sky are wrong or just abnormally high. Not very realistic, and had to divert on three occasions so I'm staying well clear.Rob


Rob Prest

 

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Guest tompeel

Well, now I just reloaded the saved flight and guess what, the problem has gone away. I just climbed back to FL370, no problem. Active Sky is running, I have values:FL370M.845TAS497TAT -12c - if my maths is correct, that's an OAT of -45c, can anyone confirm?Tom

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-45c = -49f. As a reference, -43c and -43f are equal...FSX for me? Not a chance!ChuckC-130E/H/H1 Flight EngineerDyess AFB, TXIntel Q9450 CPUASUS P5E64 WS Evolution Mobo2.0 gig Corsair DDR3 1800 TWIN3X20481800C7DFINWD 750 gig HDDSB Audigy 2XFX Nvidia 9800-GX2 Black EditionCorsair 1000 Watt PSUCoolerMaster Cosmos 1000 CaseDell 2405 24" Widescreen LCDSamsung 17" LCDCH Products USB Yoke, Pedals, Throttle QuadWindows XP Pro SP3


Chuck Blake

 

Intel Q9450 CPU

ASUS P5E64 WS Evolution Mobo

2.0 gig Corsair DDR3 1800 TWIN3X20481800C7DFIN

WD 750 gig HDD

SB Audigy 2

XFX Nvidia 9800-GX2 Black Edition

CoolerMaster UCP Series 1100w PSU

CoolerMaster Cosmos 1000 Case

Sharp LC32GP3UB 32" HD LCD

Dell 2405 24" Widescreen LCD

CH Products USB Yoke, Pedals, Throttle Quad

Windows XP Pro SP3

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Guest j-mo

>As a reference, -43c and -43f are equal...It's -40C that's equal to -40 F.Regards,

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Guest tompeel

Ok, if you prefer Fahrenheit - - at M.845 and a TAT of -22F, what is the SAT?Tom

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