I just noticed something odd - in 2004, the trim indicator on the pedestal moves incredibly fast compared to 2002 - it jumps several numbers with just one press of the button on my joystick...Anyone else seeing this?Ryan

Hi,I think you might be able to change that behavior. Take a look at this thread...http://forums.avsim.net/dcboard.php?az=sho...&topic_id=12206Let me know what you think. :)Regards,Jim Richards

Is it with flaps down? Flaps down operation of the stab trim is extremely faster than flaps up operation in real life! I have finally found mine working somewhat like it should in FS9Mark TolkaczSouthwest Virtual

"Flaps down operation of the stab trim is extremely faster than flaps up operation in real life! "737NG Manual Stab Trim should operate at 0.2 units per second with the flaps up and 0.4 units per second with the flaps extended. I don't know if the tweaks recommended in the previous message thread on this subject will provide the correct trim rate in all cases (It may also have something to do with keyboard key repetition rate settings in Windows???).The A/P, by the way, trims the aircraft at a mere 0.09 units per second with the flaps up... and 0.27 units per second with the flaps extended.Hope this helps?Cheers.Ian.

I have the stab trim mapped to a joystick button and I cut the repetition rate in the fs9 1/2 works a lot better

Thanks for the real world info Ian! You know one of the really amazing things I realized about the NG happened when I saw the control column moving in the VC while on autopilot. I think most everyone knows the default FS autopilot uses trim and not actual control surface input to fly so I think it's really cool that PMDG was able to program their autopilot to use real control surface input with only a minimal amount of trim.Ryan

Hi Ryan,I noticed the same problem. So far, I haven't found a solution. Setting the repeat rate to '0' doesn't affect the size of the trim increments (there seem to be 37 notches to cover the entire trim range from 0 to 15 - setting the recommended take-off trim of 5.25 is thus impossible).Changing the trim effectiveness in the .cfg or .air file also doesn't increase the number of notches available, it merely reduces the effect of each increment, which could adversely affect the plane's behaviour in autopilot mode. I think the solution is to change the number of increments available in the gauge itself. Obviously, that's not really user-editable... :).Cheers,Gosta. http://hifi.avsim.net/activesky/images/wxrebeta.jpg

>Thanks for the real world info Ian! You know one of the>really amazing things I realized about the NG happened when I>saw the control column moving in the VC while on autopilot. I>think most everyone knows the default FS autopilot uses trim>and not actual control surface input to fly so I think it's>really cool that PMDG was able to program their autopilot to>use real control surface input with only a minimal amount of>trim.Vertical flying by the AP is performed primarily by trim and only by colum if needed, that is the real way to do it, the ailerons are norml movement, same goes for rudder.Of course, during decent and climb the colum will work, way to be big movements for trim to do that.DennisLicensed on the B737NG and the Airbus 319-321 as a technician (B1 and B2)

"I think most everyone knows the default FS autopilot uses trim and not actual control surface input to fly so I think it's really cool that PMDG was able to program their autopilot to use real control surface input with only a minimal amount of trim."I'm impressed, too, Ryan. It is rare to find a sim which does this.Just wondering how much logic of the real aircraft has gone into the PMDG logic? Trimming logic appears to be very complex. The A/P calculates how far it can move the elevator (elevator authority) and how far it commands the elevator to move (elevator command). If the ratio of the command to the authority is too large, the autopilot trims the stabilizer to decrease this ratio.There are different elevator authorities depending on A/P modes, Total Air Pressure, Static Air Pressure, Stab Position and Flap Position. If, say, the flaps are between 0 and 7 degrees, the A/P is only allowed to move the elevator 3 degrees.... a small percentage of the full range.Cheers.Ian.

I agree with you Ryan!The low number of increments results in to large pitch trim steps which makes fine pitch control inaccurate.Hope the PMDG team will fine tune this.Haromo

FWIW, I am not seeing this. Trim speed in FS9 seems the same as it was pre-SU1 in FS8, using the buttons on my MS Precision joystick.Lee Hetherington (KBED)

Ok must be a joystick specific thing - I'll play around with the repeat rate etc...

Hi Ryan,I tried that, it doesn't change the number of increments (I use the default joystick settings with repeat turned off). I did some experimenting to see, if it's actually affected by the gauge, or if it can be modified by the airfile. For that I used a trim gauge from one of Paul Golding's panels with a numerical trim read-out, and tested it with different airfiles (non-PMDG). With one FDE, it took two clicks to go up one decimal point (i.e. from 4.0 to 4.1), while another that had really large increments showed a jump from 4.0 to 4.7 with just one click. So it seems, that at least in this case the gauge does not have a controller function, but it's merely a readout. It may be that the large increments shown on the PMDG gauge are also due to a limitation in the design of the trim indicator (it may not be able to display smaller increments).Anyway, changing the trim_effectiveness value in the flight_tuning section of the aircraft.cfg appeared to affect the autopilot behaviour, especially on altitude capture. I suspect, it may read from the airfile itself, rather than the .cfg, and thus expects a certain amount of pitch change with every increment, and as pitch doesn't change as expected, it starts playing catch-up. So I just changed the value in the airfile itself. After a few test flights, I haven't found any adverse effects, the autopilot behaves the same as before, and hand-flying climb and approach is now great fun.However, although it's very easy to change it, I'm not sure if I should post the instructions here - I'm sure PMDG won't be too pleased, if they suddenly get a lot of support requests from people who accidentally messed up their airfiles... :). But if you want to e-mail me, I'd be happy to send you the instructions.Cheers,Gosta.http://hifi.avsim.net/activesky/images/wxrebeta.jpg

Hello Ryan,You ever happen to find a good way to work this out?Jimy Richards