autopilot problem solved!

[adamschofield 0]

Have been having a fiddle with the values in the following datafile(BACKUP FIRST).C:Program FilesMicrosoft GamesFlight Simulator 9Pssboeing 777AP_control_coeffsThese values are used for the feedback controllers and altering some of the values for pitch controller have made for a much smoother transition to climb and acquiring altitude with the autopilot.OPENED WITH NOTEPADORIGINAL******************************RollOnAilACC=3.85RollOnAilDECEL=5RollOnAilINPUTSTEP=1800RollOnAilMININPUT=1000RollOnAilMAXINPUT=31000PitchOnElevatorACC=1.5 PitchOnElevatorDECEL=2 PitchOnElevatorINPUTSTEP=100 PitchOnElevatorMININPUT=-12384PitchOnElevatorMAXINPUT=14384VSonPitchACC=850VSonPitchDECEL=1500VSonPitchINPUTSTEP=2.5VSonPitchMININPUT=-15VSonPitchMAXINPUT=30SpeedOnElevatorMaxAcc=1SpeedOnElevatorDecArea=15CHANGED**************************************RollOnAilACC=3.85RollOnAilDECEL=5RollOnAilINPUTSTEP=1800RollOnAilMININPUT=1000RollOnAilMAXINPUT=31000PitchOnElevatorACC=1.6PitchOnElevatorDECEL=2PitchOnElevatorINPUTSTEP=50PitchOnElevatorMININPUT=-12384PitchOnElevatorMAXINPUT=14384VSonPitchACC=500VSonPitchDECEL=900VSonPitchINPUTSTEP=0.7VSonPitchMININPUT=-15VSonPitchMAXINPUT=30SpeedOnElevatorMaxAcc=1SpeedOnElevatorDecArea=15With just these changes there are no more abrupt pitch ups or downs with the autopilot.Please remember to backup the original file.Adam

[MarkRey 16]

Adam,Interesting find and thank you - have not tested it yet but I was contemplating adjusting these values myself (had not the patience :) ) Have you noticed any ill effects, like g/s capture problems?Abrupt alt capture was the one thing that really stood out for me at this point.regards,Markhttp://i14.photobucket.com/albums/a319/markrey/lsd2.jpghttp://i14.photobucket.com/albums/a319/mar.../sup_banner.jpgXPHomeSP2/FS9.1/3.2HT/1GIG/X700pro256

[SierraDelta 1,337]

I have flown with adjusted values since a few days after release - mine are not exactly the same as Adam's and I have also changed the first section, but there is no doubt that a little experimentation will bring immediate benefits.For me, both LOC intercept and G/S capture are smooth and I have seen no ill effects so far.Highly recommended, but I'm sure that the patch will make things even better.

[adamschofield 0]

MarkThanks for the response. I am sure that a lot of improvement too autopilot response could be achieved through fine tuning these factors. I have noticed that a few addon aircraft expose these "fiddle" factors in an external file. (PIC 737)I am sure that there must be a lot of interest out there, and I for one , would be keen on hearing other peoples thoughts and changes they have madeRegardsAdam

[Guest sb55mv]

Good Grief, I'm going to sound like a complete moron now, but, I can't locate this file thats mentioned above,is this the aircraft .cfg or the panel .cfg or something else, and is it in the main PSS 700 folder, or in the actual aircraft folder.thanks, I did not want to post this, but I just coulden't find these texts mentioned above,thanks,

[adamschofield 0]

Hello Steve.The file on my computer is atC:Program FilesMicrosoft GamesFlight Simulator 9Pssboeing 777AP_control_coeffs.datAlter with care, very slight changes can have large effects.Adam

[Guest RichR]

I can't open the AP_control_coeffs.dat file. It's not a text file, so what program will open a data file?RichR

[Guest tommy.knocker]

open it with the notepard...copy the new text, paste, close and save...that's it.ciao

[adamschofield 0]

WOULD SEEM TO GIVE GOOD STABILITY IN PITCH AND ROLL. NO ROLL ON AUTOPILOT COUPLED ILS APPROACHRollOnAilACC=3.85RollOnAilDECEL=5RollOnAilINPUTSTEP=2800RollOnAilMININPUT=1000RollOnAilMAXINPUT=31000PitchOnElevatorACC=1.6PitchOnElevatorDECEL=2PitchOnElevatorINPUTSTEP=50PitchOnElevatorMININPUT=-12384PitchOnElevatorMAXINPUT=14384VSonPitchACC=300VSonPitchDECEL=900VSonPitchINPUTSTEP=0.9VSonPitchMININPUT=-15VSonPitchMAXINPUT=30SpeedOnElevatorMaxAcc=1SpeedOnElevatorDecArea=15

[Guest FlyinJ]

Rich,1) Right-click on the file and select Open.2) When Windows presents the "Windows cannot open this file" screen, choose the "Select the program from a list" radio button and click OK.3) Scroll through the list presented and select WordPad (or Notepad as others have suggestd). Note that you have the option to "Always use the selected program to open this kind of file" if you wish.Hope this helps,Jeff

[Guest FlyinJ]

Hey now! These settings appear to work quite well. At least for me they do. Smoother level off and glideslope intercept and a little less 'tetering' on the localizer. Thanks Adam for posting these. Makes the flights a little more enjoyable while waiting for the patch.Jeff

[Guest brianlr]

Hi AdamThanks for the improvements this file provide - however, I have noticed that on approach I now have about 7 degrees of nose-up attitude on approach to landing, quite unrealistic. It also makes it impossible to see the runway without changing the point of view.Has anyone else noticed this result too?Is there a change that could fix this?Regards,Brian

[adamschofield 0]

Thankyou for replying Brian,Just tried another approach, having run the load editor, 50% fuel, and final approach speeds ranging +10 to -10 vref and full flap. Pitch angle holds at around 2 degrees up, Slower speeds gradually result in a higher angle of attack.RegardsAdam

[Guest FlyinJ]

Brian,I'm using Adam's modifications and my approach looks right on the money. Most airlines will have planned the fuel load so that at upon arriving at their destination the 777 will have approximately 10% or less fuel remaining in the tanks. The bean counters at the airlines like it that way! :) With the light load it is not uncommon for the approach speed to be somewhere in the neighborhood of 140 KIAS. And with 25-30 degrees flaps for the final approach, my T7 rides the glide slope at the proper pitch angle of about 2 degs nose up.Jeff

[Guest RichR]

Thanks to Tommoso and Jeff for the help opening this file! It is good of you to take the time to reply.I have tried the new settings and they seem to help.RichR