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MBY298

MD11 nose diving at TOD

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Hello all,I have a problem after TOD. The MD11 takes a nose dive of 4000 ft/pm every time it starts its descent after TOD. Have policy descent on 280 kt. Use ASA as weather so I always fill in all items in forcast. Pls can somebody tell me what settings I should change, getting tired of all the coffee stains on the ceiling.Pieter

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Hello Pieter.IIRC several people here stated that this behavior is normal even on the real MD11. The aircraft will catch the profile a few thousand feet down. My main source for real MD11 flying is the ITVV Martinair DVD :( and if you watch the descent into either AMS or PMI closely they really get this sort of V/S from the aircraft.To prevent the coffee spilling over the flight deck you can initiate the descent before the calculated TOD, via DES NOW in the FMC (IIRC).Regards

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I prefer the ECON settings to the POLICY setting.

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Hello,Thanks for the reply. I also found out that I can prevent the nose dive by descending prematurely and than letting the profile catch up with the descent, but thought that maybe there was something else set wrong. As far as the econ vs policy: If it does not work why put it in there in the first place?rgds, Pieter

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... If it does not work why put it in there in the first place?rgds, Pieter
What do you mean "does not work"? What doesn't work about it? Policy is usually 280kts, which allows Companies to plan their routes to arrive on-time. This is usually worth much more financially then the additional fuel burn of a less then optimum economy descent.

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FWIW, I have found that if I add one notch of spoilers immediately at the top of descent, it allows the aircraft to begin its descent much like the 747, 3 or 4K/min almost immediatley, which then catches up to the profile within the first 1 or 2K feet. As soon as the descent-profile is captured and the N1 gauges start to spool-up, I close the spoilers and the rest of the descent is smooth as can be. This is especially useful if the descent begins somewhere in the upper FL's. I have no idea if this is authorized or typically done in the RW, but it works for me :( :(

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The smoothest descents I get by editing the econ speed such that the aircraft slows down just a little as it starts the descent. For example, I will round off the descent to even numbers such as 0.82/310. Also, gotta be generous with the tailwind component, if any, when entering forecast winds. Then during descent, I do not deploy spoilers every time it asks for them but only when I feel they are necessary.Do you use the VC click spot for first notch of spoilers, Al? Or do you have a button or keycommand programmed for this? I am only aware of being able to get full spoilers with the keycommands.

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Do you use the VC click spot for first notch of spoilers, Al? Or do you have a button or keycommand programmed for this? I am only aware of being able to get full spoilers with the keycommands.
I'll have to try messin' with the econ descent speed sometime, thanks for the tip. As for my spoilers, I have it mapped to my 1st Saitek throttle lever in a custom profile programmed in a reg'd version of FSIUPC. It works like a champ for all the PMDG and LVLD planes I regualarly use. I have found that if I recapture the descent profile very soon after the T/D, I usually don't have the 'Drag Reqd' message in the ND very often during the rest of the descent; as long as RC issues the next 'cleared to' restriction with adequate time.

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