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lensman

747X spins out of control at end of flight

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Hi all,At the end of a flight, when ATC is providing vectors, the first turn ("WT1123 Turn left heading 340, descend and maintain 9000 ft" I make the change(s) on the MCP, and everything goes to heck in a handbasket.First, the commanded bank angle is exceeded. I'm pretty surea bank angle of greater than 90 degrees is not permitted ina 747. Second, the altitude control goes away. The plane will beginto descend, then start climbing back to CRZ altitude. Third, the FMC will not allow me to delete the end of the flight plan,nor will it allow me to change the speed or altitude. When I attempt to delete a flight plan leg, I get the message "INVALIDDELETE". When I try to change a flight plan leg, I get the message "INVALID ENTRY".I do not know if this is related, but the flight leveland speed calculated for legs are wrong. The flight levelis always too high, and rarely the speed is too high. The hand-entered data is correct. It's as though it has done onemore "step" in the flight level from the hand-enteredCRZ level.To summarize - is there a way to shut off the FMC navigationfunctions? I've read through the FMU manual, and tried toread the "manual approach" section of the manual. I've alsofollowed the checklists. Any pointers would be welcome - thanks!dan davison

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The aircraft can be flown by hand or using the MCP-controlled autopilot/flight director not on an FMC route. You cannot delete a current leg in the FMC but you can select a different fix and fly to it if you want to. You'll still need to use the FMC to select an instrument approach (for nav radio selection).I'm trying to play back your events in my mind, but you didn't mention to changes you made to the MCP that resulted in the unusual attitude. When things aren't going as planned, rule number one is to fly the airplane first... did you by anychance disconnect the A/P?"The flight level and speed are wrong" ... not clear at all what this means. Pointers are first, there's lots of help here but most that offer would like to see a screen shot of your panel during the problem. This provides many clues on what's happening without having to ask if you did this or was that on or off... Second: The FMC works very well but there's a steep learning curve at first because there's so many things to learn unless you're an experience pilot.. and even those have got some learning with this complex simulator. Third: I recommend using one of the tutorials for the 747.. the files may not be useful in FSX yet but the essence is still there.

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Thanks very much for the fast replies.I've been through PMDG tutorials 1, 2, and 4I will try to get a screenshot and post it later today.Thanks for pointing out that "flight level and speed are wrong". By this I mean that if my assigned FL is 260, andaccording to the FMC the next ICAO "step" is FL300, on allof the legs the FL will be 300 not 260. I'll get a screenshot of this.At some points I turn the AP (not A/T) off, but that's toregain control. As soon as things seem to be back what theyshould be, I turn the AP on, and the flight goes well untilthe next ATC-commanded turn, when the whole mess starts again.thanks all,dan davison

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