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ahinterl

MD-11 (FS9): Wrong heading after takeoff

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See attached image: After takeoff, heading switches to 19 deg for some reason, and the plane follows that when engaging the autopilot. Why does it do that?Andreas

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"Why does it do that" probably because you told it to? White text on the PFD indicates Pilot input, so I would guess that if you look at the display above the heading knob on the Glareshield, you have the number 19 dialed in. If you would like the FMS to control the direction of the aircraft, then you should consider pressing the 'NAV' button on the EFIS. Have a look at the Systems manual, Auto 30.4 and Auto 30.26 for more details.

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"Why does it do that" probably because you told it to? White text indiactes user input. I would guess that if you look at the heading knob, you have the number 19 dialed in.
Or mabye you never pulled the heading knob to tell it to fly the heading you told it to.James

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The situation was that I created a new flight by loading the FS9 default Cessna at KSEA situation then loading and configuring the MD-11. The heading on the FCP was 340 all the time, I think I can remember that this value was there already and I didn't need to dial it in (I only did a couple of changes to the knobs and switches, so I rather forget something than I do too much), and the value was never changed. No idea where the 19 comes from.Nevertheless I'll check again by creating a new situation from scratch and observing everything I do in preparing the plane.Andreas

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"Why does it do that" probably because you told it to? White text on the PFD indicates Pilot input, so I would guess that if you look at the display above the heading knob on the Glareshield, you have the number 19 dialed in.
But in that case the white dotted line on the ND should be pointing to 019 too, which it isn't: it's still pointing at 340...? AFAIK the white dotted line always moves along when turning the HDG knob.

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Jeroen, what is it that you are trying to do? Do you want to use HDG or NAV on departure? If HDG then set FCP HDG and pull knob, if NAV then press NAV button before takeoff. The FMA will annuciate the mode you have selected. Not sure how you ended up with the situation that you are describing.

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But in that case the white dotted line on the ND should be pointing to 019 too, which it isn't: it's still pointing at 340...? AFAIK the white dotted line always moves along when turning the HDG knob.
That's my understanding as well. I cannot see anywhere any setting for 19 degrees. It's like after liftoff, the plane gets a mind of its own...When I activate the AP, the plane immediately starts a right turn towards 019...(To say it with Monk's words: Can you make it a round 20, please?)Andreas

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Pleast post a screenshot of the entire panel from when this happens.

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Jeroen, what is it that you are trying to do? Do you want to use HDG or NAV on departure? If HDG then set FCP HDG and pull knob, if NAV then press NAV button before takeoff. The FMA will annuciate the mode you have selected. Not sure how you ended up with the situation that you are describing.
You're talking to the wrong guy here... :(

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I am so confused... I should get off the forum for awhile and go flying.... :(

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Tested the same at PHNL: Plane starts up with 222 in the hdg window when on rwy 22. After liftoff, HEADING 221 is announced, pretty close to 222... So, I guess the 19 for KSEA is a database error or so...Andreas

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Tested the same at PHNL: Plane starts up with 222 in the hdg window when on rwy 22. After liftoff, HEADING 221 is announced, pretty close to 222... So, I guess the 19 for KSEA is a database error or so...Andreas
Andreas,At Nose Gear Lift-off the FMA indication "TAKE OFF" will change to HEADING xxx.The heading that is shown then depends on the average heading the plane had during take-off roll between 60 and 80 kts.This is what the real plane does.AND:Just tested this on the PMDG simulation and found out it works like the real one!!!!Does Heading 019 make sense in the pictures above, if you remember the first part of the take-off roll till 80 kts?Harry

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Harry,unfortunately heading 19 makes absolutely no sense. Fire up FS9 with the default "Cessna at KSEA", this will place you at 34R if I remember right. After changing the plane to the MD-11, the FCP heading window correctly shows 340. Look at the screenshots, there's no indication of any hdg 19. The screenshots say it all, I think, and I get the same result even when I carefully look what I do when preparing the situation.Andreas

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What Ryan said: post a screenshot of the entire panel when this happens.

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Harry,unfortunately heading 19 makes absolutely no sense. Fire up FS9 with the default "Cessna at KSEA", this will place you at 34R if I remember right. After changing the plane to the MD-11, the FCP heading window correctly shows 340. Look at the screenshots, there's no indication of any hdg 19. The screenshots say it all, I think, and I get the same result even when I carefully look what I do when preparing the situation.Andreas
Andreas,Agree, heading 019 makes no sence.Was able to reproduce your scenario, both in the FS9 and FSX versions, also without "preloading" the Cessna first, and not arming NAV and PROF before T/O as I normally do in most cases.Still don't understand why these headings show up, need some more time to do more testing on this, and also wait for the oncoming update to see if this has been corrected already.Regarding screenshots:The pictures you provided say it all. Screenshots of the whole panel will not add or clearify things, as the 'after liftoff heading" is nowhere else visible nor selectable. As stated before, it's a heading calculated by the AFS between 60 and 80 kts and presented on the FMA at nosegear lift-off.Harry

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Andreas,Agree, heading 019 makes no sence.Was able to reproduce your scenario, both in the FS9 and FSX versions, also without "preloading" the Cessna first, and not arming NAV and PROF before T/O as I normally do in most cases.Still don't understand why these headings show up, need some more time to do more testing on this, and also wait for the oncoming update to see if this has been corrected already.Regarding screenshots:The pictures you provided say it all. Screenshots of the whole panel will not add or clearify things, as the 'after liftoff heading" is nowhere else visible nor selectable. As stated before, it's a heading calculated by the AFS between 60 and 80 kts and presented on the FMA at nosegear lift-off.Harry
Harry, This has not been corrected for the update. You said you have been able to reproduce. Can you provide any description/actions/steps that will always reproduce this? If I can reproduce this on my end, I will be able to fix it. Otherwise there not much I can do about it.

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Harry, This has not been corrected for the update. You said you have been able to reproduce. Can you provide any description/actions/steps that will always reproduce this? If I can reproduce this on my end, I will be able to fix it. Otherwise there not much I can do about it.
Just tried it myself Michael, Andreas is quite right - Take off from 34R at KSEA using 34R and first star in fms and at takeoff the pfd does show 019 for a short time, soon changes though. I chucked in KSEA/KSFO, clicked nav & prof and bingo - at initial lift off, pfd reads 019. Easilly reproducable.No idea why Andreas's plane starts a turn to 019 though as it vanishes from the pfd long before autopilot can be engaged.Hope this helps. (FS9 anyway, not tried FSX)John Ellison

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Harry, This has not been corrected for the update. You said you have been able to reproduce. Can you provide any description/actions/steps that will always reproduce this? If I can reproduce this on my end, I will be able to fix it. Otherwise there not much I can do about it.
Michael,There's in my opinion no "special" set-up needed, but writing this I'm starting up my FSX Vista 32b computer and will indicate my steps.Starting FSX Acceleration.Don't Run FSUIPCFree Flight current aircraft is UltralightChange: Select MD-11 GE KLM N/CCurrent location: Friday HarborChange: KSEA RWY 34RWeather Theme: = Fair WeatherWhen Inisialized:FMC KSEA/CYVRCRZ 120CI 50F-PLN: 34R, SID KMORE1TAKE OFF: Flex 50, Packs ON, Flap 20, S/W= 0/0, OAT 14C, confirm VspeedsMinimums: RA 0, Baro 1147Set STAB Trim (7.2)Dial aFlap -> 20Autobrakes T.O.Spoiler ARMTransponder RA/TASelect TRFCSlats EXT/Flaps 20Alt select 7000VOR1/VOR2HI INT ON, LDG LT EXT ONNormally I would Arm NAV and PROF now before starting the Take-Off.In this case NAV and PROF are NOT armed.starting TO:Set Full Thrust> 70% N1, set AUTOFLIGHTDuring Take-off roll, no rudder input is required nor made.At Vr a normal rotation is started.Observe FMA "TAKEOFF" changes to HEADING 016Set AutopilotSelect PROF and FMS SPD as applicable.Clean up the aircraft.At 7000: observe FMA HEADING 016, PFD HDG013 ND: HDG013, TRK is 016 (solid bowtie) , Selected HDG 343 (dotted open bowtie).Hope this will help you to reproduce as well, and find a clue.For FS9 I had repeatedly similar results but slightly different values of course due to a difference in the magnetic variation across platforms. (however both heading values are very close to the local variation.)Another thing I did yesterday was using rudder inputs - on purpose - during first part of the TO roll and had a liftoff heading of 147!!!Running default FSX scenery, no other add-ons running in the background.Regards,Harry

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