Stab Trim Indicator...

[ScottThePilot]

Hi All,

On our upper EICAS, we display the Stab Trim setting and range (doing some testing) which is currently -1 ... 10 units.  We have a FSC TQ Pro Motorized.

The MCP.INI has these lines for trim...
TrimMin= 0
TrimCtr= 5
TrimMax= 17
                              / 737 Trim Gauge Min/Ctr/Max

And in the FSC section near the bottom after calibrating the trim on TQ from within MCP...
FSCTQTrimOffset0= 64
FSCTQTrimOffset10= 138
      /Offsets Trim Indicator for Trim 0 and Trim 10


In the PMB738.TXT (under the CDU -> Types folder), the following lines appear...
TrimProportional=Off
//green band
TrimMin=2.5
TrimMax=7.0

//scale min and max
TrimScaleMin=-1    ;Not real world numbers - set to these values for proper display.
TrimScaleMax=10   ;Not real world numbers - set to these values for proper display.

-------------------------------------------
This would seem to tell me that these numbers (-1 and 10) defined here are the ones showing up on the EICAS and that they need to be changed to the real numbers.  Our actual TQ indicator...
1. Shows 0 to 17 as the range which matches the MCP.INI file
2. Shows the "Green Band" being 2.5 to 8 which pretty much matches the PMB738.TXT file.

As is obvious when moving the trim, the -1 ... 10 scale doesn't match the 0 ... 17 on the TQ no matter what setting.  So I believe I just need to make the scale on the EICAS match the actual TQ scale (0 ... 17).  I modified the PMB738.TXT file and changed the -1 and 10 to 0 and 17 to match...

TrimProportional=Off
//green band
TrimMin=2.5
TrimMax=7.0

//scale min and max
TrimScaleMin=0    ;Not real world numbers - set to these values for proper display.
TrimScaleMax=17 ;Not real world numbers - set to these values for proper display.

But when I fired up the SIM, the EICAS scale was still wrong (-1 ... 10).  Is there a Glass Cockpit INI that needs to change also?  Did I miss something else?

Thanks for any help...
Scott

[ScottThePilot]

Just a quick update...

I exampled the PMB738.TXT that was under the CDU/Types folder.  I looked that the GC folders for Capt, F/O and Upper EICAS and they all have a .TXT file also.  They all have the same -1 to 10 scale as in the one is CDU/Types folder.  I changed the scale to 0 .. 17 in a couple of these and also the main CDU/Types file but the EICAS still shows -1 .. 10 as the scale. 

I just don't know what the file to modify to change that scale to match the TQ indicator.  hoping someone can help with this config item as I am at a loss where else to look.

Scott

[Trevor Hale]

Thats a good question.  I am not sure if it is even possible as that is part of the graphic.
May want to email Enrico about that one.
Support@projectmagenta.com

[ScottThePilot]

Hey Trevor,

Thanks for taking a look here.  I did email Enrico about how this works and which file to modify.  It is just a number so while it is drawn by the graphics, it should be redrawn just fine just like any engine number as throttles are moved.  I hope that I understood your comment correctly.

After reading the manual some more, The PMB738.TXT file in the CDU/Types folder is the one we should be able to edit (and select in the FMC) and would load the right scale.  I believe the file gets copied to the NETDIR so that all machines can pull from the file.  I just haven't been able to find the right file to edit I guess.

Will let you know...

Also Trevor, can you take a look at my other post on the MCP.INI file and how the command bars operate.  Perhaps you can try it and let me know if my theory is true.

Thanks,
Scott