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Pitch command?

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I am having an issue getting the pitch command to control the aircraft's pitch. Most assuredly I am not doing something correctly. I've read the excellent "AutoFlight2.pdf" but it doesn't really explain what is required for the pitch command to work...other than the "ALT HOLD" has to be off, Glide slope must not be captured and not be in a GO AROUND. None of these were the problem. Can someone tell me what else may be holding me out IE, hydraulic pump line-up, FD switching error or Sperry 77 switching error? Thanks for any ideas. So far everything else is working quite well and I love the work that was put into this aircraft! Vic

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The Sperry 77 does not have a pitch command mode, as in real life. Autopilot pitch (except during an automatic coupled ILS approach) is controlled exclusively by control wheel steering, provided the pitch axis of the A/P is engaged.RegardsBob ScottATP IMEL Gulfstream II-III-IV-V L-300Santiago de Chile

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Sorry, Bob...I may not have been clear. I realize the 77 doesn't do the pitch control, but rather, the "Pitch CMD" control on what I think of as the Flight Director panel to the left of the Sperry. I was wondering if something I had done incorrrectly, on the 77 as an example, but also anywhere else, would be preventing it from working? Here is a small screen shot to explain (hopefully better than my words!) ;-) http://forums.avsim.net/user_files/154494.jpg What else can I check, other than having the "elevator" engaged?

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"Sorry, Bob...I may not have been clear. I realize the 77 doesn't do the pitch control, but rather, the "Pitch CMD" control on what I think of as the Flight Director panel to the left of the Sperry. I was wondering if something I had done incorrrectly, on the 77 as an example, but also anywhere else, would be preventing it from working?"Hi Vic,Let me try to help. The flight director is not coupled to the autopilot in any way. Therefore adjusting the FD Pitch knob does nothing for you.Here's what works for me. After liftoff, I use the yoke Y Axis (Elevator Axis) to establish the pitch that I want. Then I use pitch trim until I can release the yoke and still maintain my desired pitch. When the yoke Y Axis is relaxed and centered (this is very important, I even take my hands off to insure that it is centered), then flip the autoplilot "ELEV" paddle to the "ENGAGED" (up) position. The autopilot will hold that pitch. To change pitch, push or pull the yoke. When you again center the yoke, the autopilot will hold the new pitch setting. When you attain the desire altitude, then activate the autopilot "ALT HOLD" switch.To descend, set the "ALT HOLD" switch to "OFF" and push the yoke forward. When you get the pitch you want (I cheat a little here and use the VSI to determine my rate of descent), release the yoke. Again the autopilot will maintain the pitch for you. On an ILS approach, I continue using th AP pitch hold until I am under the glideslope and aligning myselt with then localizer, then I level off ("ALT HOLD" switch) and set the switch on the left (I don't remember the exact name but it's the heading mode switch) to "AUTO APP." I insure that the localizer is captured while I'm still below the glideslope and as I fly through the glidepath, pitch hold will disengage automatically and the plane will descend on the glidepath.I hope that I have understood your problem and I hope that this has benn helpful to you.R-EDITED: to correct typos.

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You are adjusting the F/D only.The Autopilot system is independent of the FD.You must engage the ELEV channel for the AP provide CWS in the pitch axys.You are trying to control pitch through the FD, but the autopilot and the flight director systems work independent from each other. Also, you only will be able to use the Altitude Hold and Turbulence modes with the ELEV Channel Engaged.

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OK...I got it now. Due to a 707 payware add-on I have (names withheld to protect the guilty), which incorrectly allows that FD "PITCH CTRL" knob to control the actual aircraft's pitch (not just the FD's indication on the HSI) I learned an incorrect and bad habit! At least I'm guessing the 707 is incorrect in that respect. Did the 732 have one of these? http://forums.avsim.net/user_files/154505.jpg Thanks so much, guys!! Vic

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It was replaced for the CWS.you input your pitch through Yoke moviment, and the ap do the rest to keep it. IF you aren't in ALT HOLD. the same is valid for the wing roll. If you aren't using the hdg/vor-loc/man GS, in capture mode as you can see in the FMA.Armed - AmberCapture - Green

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Where is the trim adjusted in the cockpit screen, BTW? I have not been able to find the "spot" on the "throttle quadrant" display? (I'm guessing it should be there?). I can adjust "Trim" with my controller...but I have it set VERY fine, in FSUIPC, for exact trim control and it's a bit slow for the "climb out" corrections you mentioned. The keyboard keys are disabled for "trim" as they seem to interfere with the FSUIPC settings for my controller buttons? Are there trim "click spots"? Again, thank you guys...I could have been on this wild goose chase forever if not for your help. Vic

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Thanks! The whole "CWS" term was throwing me off. NOW I see how it is supposed to work LOL! Vic

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Wow! I take it that this is "as real as it get's" to a 732 "Tinmouse"?? Because, thanks to all your help, I've got my little mouse cruising along at .72 mach, over Montana on my way to the Big Apple! The CWS explanation you guys gave was a total enlightenment for me...and it works just like you said it would. What a great job you all have done! Yeah, I've got lots of "high-bypass, NG" 737's...but I'll always have my mouse!! I love her!*EDIT* Oh...BTW...did I mention how much I love NO VC?? I can look anywhere, with my hat switch and...BANG...no delay, I'm looking out the window without waiting for terrain to load! Thank you so much, gang! Vic

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Thanks Macs. Is there a "click spot", somewhere on the panel, to adjust elevator trim? I thought it would be on the "throttle quadrant" as it has an elevator trim wheel shown...but nothing happens (see screen shot).http://forums.avsim.net/user_files/154516.jpg The reason I ask is that I have my trim buttons, on my controller, set to a VERY fine setting, in FSUIPC, and I'm used to having a "click spot", somewhere on my panels, for quicker, courser, changes. Thanks. Vic

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Elevator Trim is ignored while Autopilot Pitch Hold is Engaged. To adjust Elevator Trim, disengage Autopilot Pitch Hold ("ELEV" paddle switch down), adjust trim, then engage Autopilot Pitch Hold.You can adjust the pitch without disengaging Pitch Hold by using the yoke or joystick Y axis.R-

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So...if I understand, you can only adjust elevator trim with a controller or the keyboard, but not with the mouse anywhere in the cockpit? Thanks. Vic

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Vic, You might need to re-adjust your technique with trim if flying by hand as I don't beleive there are any clickspots for trim in the trim portion of the throttle quadrant. If I could suggest a way to deal with this, I would have it mapped to two buttons or a HAT switch on my (yours :) )joystick, and have it at an intermediate sensitivity; this actually works well for me. I really don't use much trim time-wise, only at departure and until the approach phase I want to take-over on. The AP trim "autotrims" for you , so again, there is no need to mess with this most of the time. I am curious as to how you would manage flying on instruments by hand and having to open the throttle quadrant window during the same period of time to adjust for trim :( It seems to me it would be a lot of unnecesarry work, since it is on the way of most of the panel. Anyway, hope this helps,regards,Macs :)

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