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Guest meirumeiru

auto thrust after landing (and in the last seconds on final)

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What am I doing wrong? I'm flying the ILS approaches manually... therefore I disable the autopilot (yellow button on the yoke) ... this disables the autoflight, but not the auto-thrust... I'm also arming the spoilers and setting autobreak to "max" (or something else, other than off or t.o.)... but... on short final, the aircraft does nothing (not retarding) and even after touchdown (which is pretty difficult, when the engines run at full power), I can't make them stop... and, even disabling auto-thrust (standard FSX key) does not disable anything... and when I manually push the key on the throttles, it only disables for a short time... it's impossible to get the reverse thrust working...strangely I don't have this on every flight... but... on many... so... I think that's something I still don't understand... maybe someone could explain me this a bit more?(some things at takeoff are also pretty difficult to understand... e.g. if you press FMS while taxiing, right after pressing autoflight and arming NAV, then the whole auto-thrust does not work anymore... there's no "to-speed" and no "to-clamp" ... you'll have to do everything manually then... but it's not visible, wheter or not you're in such a state or if everything works normally) ... after takeoff you can reengage the system by pressing FMS again... but not before... at least, I wasn't able to find out how...Rudolf

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Be sure to pull the throttle back to idle at about 40 feet AGL or so, even when landing on autothrottle. I have the F2 key (reverse thrust) mapped to a button on my CH Products controller, and reverse thrust works fine after touchdown for me.I don't believe you should be pressing FMS during taxi at all...set your take-off parameters at the gate, and arm NAV and AUTOFLIGHT during the taxi.I'm still learning and welcome any further information on these issues.

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First off, it is very unusual to fly an approach with an autothrottle equpped aircraft with the autothrottle off. So you're initial setup should be fine--autopilot off and autothrottle on. So moving on...The MD-11, even when flying the ILS manually, should auto-retard the throttles to idle starting 40-50' radar altimeter. On touchdown they should then disconnect and you can then unlock and bring up the reversers. With all that said, I don't know why you're having problems. That's what is supposed to happen, but clearly it isn't. Do you have add-on scenery or mesh installed? I heard somewhere that the radar altitude goes to the default mesh, so if you have an aftermarket mesh or airport the airplane could still think you're 10-20' in the air. Never had a problem myself, but just a thought.Eric Szczesniak

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Do you have add-on scenery or mesh installed? I heard somewhere that the radar altitude goes to the default mesh, so if you have an aftermarket mesh or airport the airplane could still think you're 10-20' in the air. Never had a problem myself, but just a thought.
First off, you need to sign your full name in posts per forum rules, thanks (or add it to your sig like many of us do).That's good advice at the end of you comment. Most of the time I don't have any issues with AT staying locked on, but have had that problem at a couple airports,,, I only wish I remember which ones. Your answer may have been what it was. I'll check their elevations if it ever happens again.Thanks for the tip.

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I'm trying to figure out what the OP is actually having trouble with. Is he saying the ATS stays on after TD and won't disengage at 50' AGL? I don't understand the point about the plane not doing anything on short final. What does this mean? If you are flying manually, then what is supposed to happen? Are you talking about ATS specifically not working on final?As far as I can tell, you might have your throttle controller active, thus preventing the reverse thrust from working. You need to be idle and have a null below idle in your hardware setup or you can have trouble.What do you mean by pressing FMS? Do you mean FMS SPD? If so, then I don't think you need to mess with that, in fact pressing PROF is the way to go. I find arming PROF on the ground works best. Setup the FMS/plane and press PROF. Then line up with the runway and press AUTOFLIGHT to engage the ATS system. Make sure the heading is lined up with the runway by pressing the heading knob or dial in the desired heading. Then advance the throttles slowly until the ATS kicks in. Floor your hardware throttle (should have null above that zone as well to prevent noise) and let the plane maintain takeoff thrust. At 100 feet AGL or above press AUTOFLIGHT to turn on AP (make sure you are trimmed properly). 100 feet is pretty quick and I don't know who would do that, but I have engaged more like 1,000 feet AGL myself. Above 400 feet, if PROF is not already armed and active, then you may press it, same with NAV. PROF mode engages both FMS speed and FCP-dialed altitude, so it's your best mode. I never touch FMS SPD, unless I need to override the FMS speed, then go back.

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I too am a little unclear as to the problem you are having on a hand flown approach, and I personally am using the FS9 version, but without being a total expert on the MD-11 (but always trying!) I can tell you that disabling the A/P will not effect the A/T. If you are going to dip below the minimal speed on approach, low speed protection is going to kick in and throttle up the airplane. I believe this is due to the FADEC (which you could disable all three switches on approach, but that's not too realistic). As I always fly in VC, I sometimes click the A/T disarm button on the side of the thrust levers (I believe you have to click it twice), but I cant say with certainty if this totally disables the A/T if you require low speed protection. Also, if the thrust lever on your controller isnt at full idle just before touchdown, it is possible that the sim is detecting that your thottles should be advanced, so it advances them in the sim. Just some stuff I have figured out on my own by trial and error. In either case, I have mastered (to my own satisfaction) ILS approaches on the MD-11 and dont have any problems with the auto pilot on approach anymore. It's a complex sim (fortunately) and takes time to get it right.

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I always fly the manual approaches with autothrottle because the simulated environment lacks all the clues one receives in a real cockpit and my cheap throttle is just a toy. So, I let the aircraft maintain the speed I set into the SPD dial. Never had a problem with hitting F1 at 30-50 ft and F2 for reverse thrust once mains are planted for reverse thrust.

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