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Tone89

MD-11: Speed management issue

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Hi everyone, I've been having an issue with the MD-11 for a while now. I've been through the tutorial 5/6 times already, and I'm struggling to find a solution. I'm doing the flight from EGLL-LSZH and everything is going smoothly, I cross the top of descent fix, and begin descending. According to the tutorial, the aircraft levels off at 10000ft to meet the 250kts speed restriction, there is a 10000/250kts fix on the PFD showing the point where I reach 10000, however, the aircraft just goes straight through it and continues to cross 10000 at some 320kts! The vert rev page also shows that this restriction is in place. This unfortunately has a ripple effect for the rest of the flight, apparantly half way between the initial approach fix (GIPOL) and the following fix (TRA/10) the FMS speed should be reduced to 180kts (again no success there) even deploying the speedbrakes means I am touching down at around 240kts and as a result the autoland just doesn't touch down properly. I understand that this is a complex aircraft and I'm very impressed with it, but if someone could clarify where I'm going wrong, (I am following the tutorial word for word), that would be much appreciated. Kind Regards, Anthony Hammond.

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If the speed number above the IAS tape is in white then you are not using A/T. Make sure it is magenta, try pressing the PROF button. Yeah, landing at 240 kts would result in blown tires and a big mess to clean up. You've lost speed control... I am trying to remember away from my workstation if the SPD button should be pressed. I might need help.

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If the speed number above the IAS tape is in white then you are not using A/T. Make sure it is magenta, try pressing the PROF button. Yeah, landing at 240 kts would result in blown tires and a big mess to clean up. You've lost speed control... I am trying to remember away from my workstation if the SPD button should be pressed. I might need help.
Yeah, the speed number above the IAS tape is in white, with 'THRUST' at the top. When pressing PROF, the aircraft follows the descent profile perfectly fine but does not manage speed at all. Though I cannot physically control the throttles, I can alter the IAS selector and select a desired speed, but speed is not affected at all.

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Yeah, the speed number above the IAS tape is in white, with 'THRUST' at the top. When pressing PROF, the aircraft follows the descent profile perfectly fine but does not manage speed at all. Though I cannot physically control the throttles, I can alter the IAS selector and select a desired speed, but speed is not affected at all.
Push the FMS SPD button to change the speed above the speed tape and white THRUST to magenta. Now the autothrottle will command fms speed if using thrust for speed or will use pitch to maintain fms speed depending on the selected vertical mode.Adam

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Push the FMS SPD button to change the speed above the speed tape and white THRUST to magenta. Now the autothrottle will command fms speed if using thrust for speed or will use pitch to maintain fms speed depending on the selected vertical mode.Adam
Thanks for your reply, I'm going to give the tutorial another go tonight. Though there is no direction in the tutorial to enable this, I'm going to take your word for it :). Thanks, Anthony.

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Thanks for your reply, I'm going to give the tutorial another go tonight. Though there is no direction in the tutorial to enable this, I'm going to take your word for it :).
I think it's in FMS SPD mode by default from when you first pressed PROF, and probably you pushed or pulled the speed knob at some point to hold the speed.(I have another problem entirely which is that when I hand fly the approach the aircraft decides it doesn't want to touch down and applies full thrust as soon as I do!)

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Rob,it sounds like you have ATS still engaged. Turning off the AP does not disengage AT, to do that requires you to press the AT disengage button on the throttle levers...If you use managed thrust on approach while hand flying, it is best to set your throttle controller axis to zero, as sometimes the system reads that as a thrust request when ATS sets idle for the flare. It is mentioned somewhere in the tutorial I believe, though i am not 100% certain of this...I have done a couple of approaches into TNCM using this, and the aircraft hasn't gone into GA...Just a thought...Hope you sort the issue out...Andrew

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