Was wondering if anyone was able to add any ISG FMS or GNSS/GNS-XLS?

Hi Caribflyer,

I have installed the ISG MCU and Smiths FMS unit. It only follows LNAV since there isn't an auto throttle system on the 727.

You could also add a MFD if you want in the 2d panel. For traffic awareness I use the TCAS II freeware gauge that I made an earlier post on.

Here is my panel modifications:

[Window Titles]
WindowXX=ISG1 MCU
WindowXX=ISG1 SMITHS FMS

[WindowXX]
Background_color=0,0,0
size_mm=312,214
position=4
window_pos= 0.1541,0.3133
window_size=0.1888,0.2044
visible=0
ident=4001

gauge00=isg1!MCU,  0,0,312,214

[WindowXX]
Background_color=0,0,0
size_mm=197,271
window_size_ratio=1.000  
visible=0
ident=4004
window_pos = 0.7402, 0.4122
window_size= 0.250, 0.500

gauge00=isg1!SMITHS_FMS,  0,0,140,271

wrote on Oct 10^th, 2013 at 8:46pm:

It only follows LNAV since there isn't an auto throttle system on the 727.

The Autothrottle is available in the 727. It is actually usable, but you need to ARM it first (the default Keyboard Command is CTRL+SHIFT+R). I modified mine (for testing purposes) so that I don't need to ARM the A/T first by editing the aircraft.cfg.

Open the aircraft.cfg in Notepad, find the [autopilot] section, change autothrottle_arming_required=1 to autothrottle_arming_required=0, then you don't need to ARM the A/T.

Pressing CTRL+R (default Keyboard Command for turning the A/T ON) sets the speed to that which the 727 is doing when you pres CTRL+R. The Speed Bug doesn't control the A/T, so unless you can use the ISG A/T to control the 727's speed, I guess it might be pointless using it. Pressing CTRL+R a second time turns the A/T OFF, so you can use the throttle controls to increase/decrease the speed, the press CRL+R again to reset it to the new speed.

This is really cheating, but it sure could come in handy! NOTE: I don't use A/T in the 727 myself, so I'm just letting you know that it IS there and IS available for use. ;)

Thanks Mark  ;). Does it work with the ISG VNAV function? That is the next question.

I will give it a try sometime.

wrote on Oct 12^th, 2013 at 2:20am:

Thanks Mark  ;). Does it work with the ISG VNAV function? That is the next question. I will give it a try sometime.

It's no good asking me, I don't have ISG. :-/

I was just saying that because the autothrottle is available in the [autopilot] section of the aircraft.cfg file, it might work with ISG. This will depend on how ISG handle the A/T. It just might work. ;)

Do you need the LNAV button to activate the FMS route?

There is an LNAV select ON/OFF key on the MCU.

Make sure you have the heading select on before you activate the LNAV. ISG's LNAV system will give commands to the aircrafts heading select automatically.

I installed the ISG into my 727 with no issues, what I wound up doing after the first install was to change it so that the MCU was sitting next to autopilot panel.  Add a hot button on my yoke and when I press it I get the MCU/autopilot at the top right of my screen.  The FMS I wound up replacing it with the Garmin.  

It flies perfect so now I can do RNAV SIDS/STARS.  The only thing that I have to figure out is how to get the CDI to work with it, so that when I want to track the course by hand instead of autopilot the CDI is responsive to the FMS and then when shooting the ILS I can revert it back.  I could probably add a switch that does NAV/GPS, unless I am missing something already there.

I added a NAV/GPS switch (Cessna!Nav_GPS_Annunciator and Cessna!Nav GPS Switch) to the 2D Autopilot Panel.

Alternatively, you could assign a Keyboard Command to Nav 1/GPS (toggle). I assigned CTRL+SHIFT+N.

Tried it last night, took my panel maker program and tried 3 or 4 different GPS/NAV switches.  None had the desired effect I was looking for.  I am trying to get the RMI/CDI to work in conjunction with the ISG FMS.  So that if I switch to GPS the CDI responds in kind.  

But no worries, that is the fun of this!

Did notice one added benefit with the ISG MCU.  There is a button marked FL,  I was at 12500 and it showed it, then below it had a space that I input a new altitude.  I put in 14000 and pressed enter, the planes autopilot was on altitude hold, it climbed and leveled off at 14000.  So not too bad of an unexpected gift!

With the 727 you can cheat with a climb anyway. I do this by pressing CTRL+SHIFT+Z then plus (+) or minus (-) - the keyboard shortcut for A/P Altitude bug (select). Of course I have to count each press of the plus or minus (not good if you press to quickly) to get an idea of the altitude I am setting it to, so I prefer to use that when I haven't clicked on the Altitude Hold button at the correct time so I am only 100 feet off (one press of plus or minus). You at least get to enter the actual altitude that you want it to hold/climb to and hold.
;D