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Guest kloker

Altitude settings, FMC TOD, and ATC

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Is there a rule of thumb for maximum altitude settings for a particular distance of a flight? Because of time constraints, most of my flights are probably shorter than 737 real life, usually less than 200 miles. Several times ATC (Radar Contact) has not started my descent until after the FMC TOD. This makes the FMC, and me, a little confused. If I recall correctly, the FMC goes out of CRZ mode into DES mode and the engines start to retard speed. There's probably a fix via the FMC for this, and I may have stopped the problem by not flying so high, but what I am curious about is max altitude height vs. a distance of flight. I'm concerned just about the max altitude, not settings for ATC rules or weather. My only real world knowledge of some possible value is that I flew (in a 757) from Pittsburg to BWI, a 40 minute flight, great circle distance about 185 nm, at FL290.One thing about the FMC, the more I use it, the better I like it. That thing is great!Keith

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Hi Keith,On perf init page you'll find the trip alt, which is an FMC suggestion of the highest alt for a few minutes cruize time, given you weight and other interesting parameters.So in general, choose your cruize alt below or at (max) trip alt if you're on a short FP.Now, second question : if ATC does not order you to descent at FMC calculated TOD, just don't reset your MCP alt. You will sequence the TOD and stay at cruize alt.As soon as ATC directs you to descend, reset your MCP alt, and there you start descending (this is true for the time being, but won't be after 800-900 upgrade, as the right thing after sequencing TOD with MCP not reset is going to ALT HOLD or VNAV ALT, if this option is enabled).Hope this helpsanthonyAnthony MertonPrecision Manuals Developmenthttp://www.precisionmanuals.com

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Anthony,Hey, thanks for that! I had not noticed it was suggesting an altitude. Actually, I had not always been entering all the info I needed (ah, the learning curve)- such as setting up at least the destination as a direct route. That meant that VNAV would not engage during climb out. So I think that's why no recommended altitude. Also, the FMC is a lot more intuitive than I realized; you just follow the prompts for the next screen and everything gets loaded.As for the 800/900, I was recently in a Southwest 737-800 and they have the new upgraded color screen FMCs. Will PMDG's FMC screen be in color?Keith

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Just keep in mind that anywhere on the FMC screen that presents you with BOX prompts is a required entry and dashes --- are not mandatory items. The color digits on the FMC screen is an airliner specific option, this was brought up but I doubt that we will see this at this late date, if it was implemented it would be a PMDG-MENU item only...[h4]Best Wishes,Randy J. Smithhttp://www.precisionmanuals.com/images/forum/betaimg.jpgAMD 64 3200+ | ASUS KV8 DELUXE | GFORCE 5700 ULTRA @535/1000 | WD SATA 80 GIG | 512 DDR 400 |

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