I just loaded a saved LNAV/VNAV flight from earlier this week on descent into WMKL at 6000', and all was fine except I suddenly noticed that there was no thrust displayed on the FMA--it was grey in the upper left side. I clicked AT off and then on again but no joy. I turned off the FD and the AT off and on too, but no joy. I then noticed that even with AT switched on, I apparently had control over N1 with my CH throttle quadrant levers which surprised me greatly. So I hand controlled thrust in to TD.I've never had any serious issues with AT on this bird. The only other thing I have had previously is that in a non-LNAV/VNAV flight, the SPD on the MCP was clicked off on reloading a saved situation and I just clicked it on and bingo! all worked A-OK.What happened tonight and what should I do in such circumstances in the future ?Appreciate any guidance, thanks!Jonathan

Maybe someone can help us both. I get the same thing sometimes on saved, midroute flights with the Lnav/Vnav mode set. I've found that persistance is often the only answer. I just keep clickin' FD. . . AP > > > AT . . . whatever I can get my mouse on till I finally get something in the thrust FMA. Try going to altitude hold, FLCH or some non-Vnav pitch mode, then pressing "SPD." Sometimes that works. Once you get anything in the left FMA, you're home free. Then sometimes just a 'normal' re-press of Vnav gets it. A Bit Buggy.

Hmm, no joy.This morning, I loaded two saved flights from last night, each in LNAV and VNAV and the autothrust system of the 744 is broke in each situation. The AT does not react and does not connect at all for these saved flights now. There is a blank space in the FMA area in the top left where there would be a thrust indicator. The throttles remain reactive to manual inputs which is exceedingly strange since they are not supposed to be responsive once AT is connected and they have always been thus.I just loaded another saved situation and the commanded speed was set to IAS 100 at 4000' (!) which is totally erroneous. It changed to 250 but about 1-2 mins later. Still no autothrust.I cannot figure out what has happened or why. I am clicking my way around the MCP but there is not the slightest sign of "life" in the AT system. It is dead.Any other ideas?Jonathan

Well, (this is classic--Murphy's Law!) right after posting the above reply, I managed to get the AT to reconnect by (1) clicking the ALT HOLD first and then clicking MCP SPD button. This restored the AT annunciator and the throttles reacted immediately. I then clicked VNAV to restore VNAV flight. This procedure seems to work for the saved flights in various phases under with LNAV/VNAV control. I have observed that AT is sometimes cut off right away after doing something like changing views in the Queen (i.e., 2D to VC or SPOT and then back to 2D panel), and also just now, during flight, when I went in to the PMDG keyboard command menu to look at the MCP keyboard commands, and exited back to the cockpit, the AT disconnected again right away! So it was then > ALT HOLD click, and MCP SPD button click and presto! the AT was restored.I also have observed that in several saved flight files, the commanded IAS drops drastically to a ridiculous and non-programmed speed when loading those files. On one flight the PFD speedtape read IAS 100 and in another file, where the Queen was in VNAV ALT at FL130, the IAS read 200 on activation when the FMC had a commanded climb speed of IAS 314.Last, when loading such files, especially those in climb or level flight, the Queen yanks the nose steeply up for a couple of moments before the elevator kicks in to push it back down. This has the potential to cause serious control problems.Perhaps I have missed all the forum posts on this stuff since I came to this party relatively late. Is this my PC or me or is there a known glitch with the AT (and loading saved files) generally?Jonathan

HiI also experienced this when loading a saved situation in mid-flight. Reselecting a thrust mode like SPD or VNAV (despite the fact that the VNAV pitch mode was active) seemed to help the autothrottle to regain control.Hope it helpsEDIT: I see you got the same idea, but were typing faster than me ;-)

.precisionmanuals.com/images/forum/supporter.jpgHi GuysCheck the 747-400 Manual Title "00_Title_and_Menus_747-400" Pages 14 & 15When you want to save a flight first go to the PMDG Menu and save the Panel state.Then save your flight in MFS.When you reload your flight also load the panel state you saved.Hope this helpsA Paterson

What?! You mean it's supposed to be a 2-stage process? I have saved 20+ flights so far, mostly non FMC flightplan flights, in the standard FS9 way, and they do generally get saved well. The only significant glitch is the AT stuff I posted about (and the ILS which is minor). I'll look at the manual anyway.Thanks.Jonathan

The other more simple option would be to just click LNAV. Even though LNAV is active a second click will re-engage the autothrottle.Hope this helps guysDaniel

Wow, really? I must try that tonite!Jonathan

No problem JonathanDaniel

Hmm, if I click VNAV, then AT re-activates normally. Nothing with clicking LNAV.Another minor glitch: the commanded IAS drops reloads at exactly 100 if in VNAV ALT when reloading the saved flight. I then have to enter SPD/VS mode, enter IAS 250 to accelerate and stabilize, resume VNAV climb, and when the Mach speed exceeds M0.40 on the PFD, the commanded IAS flips from 100 to 250.Not what I would expect (or want), but it is definitely "magic" of some sort !Currently in VNAV ALT at 9000' and IAS 250, and all's well aboard the Queen.Jonathan

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Yeah, a good method to stabilize. We all develop our own informal SOPs eventually, don't we? How about this:When I reload a saved flight that is in VNAV ALT, the Queen typically kicks forward and leaps upward strongly to about 5000fpm for a brief moment. Even though AT is not annunciated as ON, the AT kicks in from the pitch-up and then as the Queen starts to nose down to the VNAV ALT level, I dial in a higher MCP ALT, press VNAV and promptly hit the MCP ALT button. N1 rises as THR REF kicks in and off I go into a restored VNAV climb. No stabilizing, to be sure, but this procedure HAS to be worth an FS chuckle, eh?Lucky for us as pax and simmers that there's no such thing as reloading a saved flight in real life!Jonathan

Next time I see that seat belt light come on, they're gonna have no idea what I'm grinning about.

Re: Saving flightsALL you need to do is save your flight from the MSFS File menu! This automatically does the same thing that saving the panel state from the PMDG menu does, plus it associates it with the FS saved flight.Doing this creates 4 files with the same prefix name (which you typed):A .flt and a .wx in My DocumentsFlight Simulator FilesA .sav and a .rte in PMDG747400PanelStateThe only time you'd need to use the PMDG panel state save feature by itself is if you're trying to create something like a Cold and Dark file or some other sort of preflight file that doesn't have the FMC programmed yet.