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shortspecialbus

Unable to control pitch with AP off

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I was descending to PHNL via ATC instructions that were having me do heading changes via heading knob and altitude changes via altitude knob and pulling it. Eventually, I was cleared for the visual approach so I hit the AP Soft Disconnect button on the yoke twice. I was then able to turn the plane, but I had no pitch control at all!The PFD stated that the autopilot was off, but the ATS was in "PITCH" mode. I couldn't get it out of that for the life of me. I was unable to climb nor descend, and I ended up doing a sort of go-around and just setting up an autoland on the ILS, which worked just fine.I am about 100% sure that I simply missed something, but a quick scan of the manuals and the ops page showed that hitting the AP Soft Disconnect button should have worked.What should I have done here? I don't have screenshots, unfortunately, as I was in a bit of a rush and forgot to take them. What are the exact steps to take the plane from autoflight into manual flight with ATS control still active? I looked at the Advanced Tutorial, but all it says is to hit the soft disconnect button, unless I missed something in my quick scan of it. As I said, I had roll control just fine, but no pitch control whatsoever. The yoke is set up properly, and the yoke was moving in the VC when I tried to change pitch, but the plane just held altitude. I also tried changing the altitude on the FCP and pulling, but it still kinda hung out at 3000 feet.Thanks,-stefan

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Anyone?-stefan
If it only happened once then I cant suggest much. You push the disconnect button twice on your yoke and you 'should' have full control. You say you only had partial control, since you got the machine back down with Autoland in your situation I would have then selected the config page and done a full Flight control test.Regards

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If it only happened once then I cant suggest much. You push the disconnect button twice on your yoke and you 'should' have full control. You say you only had partial control, since you got the machine back down with Autoland in your situation I would have then selected the config page and done a full Flight control test.Regards
Update on this: I'm pretty sure I was unable to control pitch because the ATS was in "PITCH" mode rather than thrust mode. I had disconnected the autopilot while doing an IDLE CLAMP descent to 4000. I did another test flight today where I disconnected the autopilot when lined up on the ILS at KDCA (that's a pretty short runway, by the way, ha) and was able to control everything fine. I had pressed "FMS SPEED" and the ATS was in "THRUST" mode, and all worked as expected.How does one get the throttle out of PITCH mode and into THRUST mode? I haven't been able to find the relevant section in the manuals, but I might be looking for the wrong thing.-stefan

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Try AUTO.10.26 in the systems manual.
Hmm, I've read over that and not seen what I'm looking for. I'll see if I can reproduce this and get some screenshots of the PFD, as I can't remember the modes as well as I'd like.One thing I did have on my successful flight yesterday: The entire descent, the autopilot would stop descending approximately 250 feet above my selected altitude in the FCP. This happened with numerous altitudes until I selected 2200 for a cleared approach altitude, and then it went to the exact attitude. The altitude remained highlighted in yellow, and re-pulling the altitude knob did not remedy the situation. (I was selecting altitudes with the knob and pulling when cleared by ATC.) Anyone know why that happened?Thanks again,-stefan

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The yellow altitudes means they are different from constraints in the flight plan, they will turn magenta when there is a match.Screenies are a great way to explain a problem.

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The yellow altitudes means they are different from constraints in the flight plan, they will turn magenta when there is a match.Screenies are a great way to explain a problem.
Right, but my point was that they were between 220-250 off of the selected altitude. Yeah, screenshots are certainly more useful, and I usually include them. The problem was that I was attempting to show a friend the MD-11, so couldn't really do screenshots. I'll try to reproduce.-stefan

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Right, but my point was that they were between 220-250 off of the selected altitude.
Stefan,could it be that you're having two different altimeter settings for CAPT and FO?For your other problem: When disconnecting the autopilot you should ALWAYS be able to manually control pitch, regardless of whether ATS is in PITCH or THRUST mode. This can't be it...Markus

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Stefan,could it be that you're having two different altimeter settings for CAPT and FO?For your other problem: When disconnecting the autopilot you should ALWAYS be able to manually control pitch, regardless of whether ATS is in PITCH or THRUST mode. This can't be it...Markus
Hi Markus,Thanks for the response. It's likely that the altimeter settings were different for CAPT and FO. That would make sense, actually. Does AP2 use the FO settings? I generally don't touch those.I'll try to find time tomorrow to recreate the situation where I couldn't control pitch at all, screenshot it, save the flight, and e-mail you guys the files. The only thing I'm 100% sure of is that the controls were working, as the yoke in the VC was moving with my yoke.Thanks again,-stefan

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