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Mark
08-11-2007, 05:54 AM
Will the TruTrak DigiFlight 11VSGV couple to the ILS glideslope?

Mark

aadamson
08-11-2007, 07:46 AM
Depends (don't you just love that response :) ).

The DF II VSGV really knows nothing about and ILS signal, or any form of vertical nav that could come from a NAV receiever. It order to do what you are wanting to do you'd need the AP-100 or the Sorcerer.

BUT, we need to know another variable. What other device will you be hooking it to? For example. Some of the EFIS systems will generate a synthisized approach and will in turn generate the vertical guidance that the VSGV wants to see.

In effect they do the following
a) when hooked to an SL-30 for example, the take digital steering commands from the SL-30
b) process those commands into the equivalent ARINC vertical commands
c) display them on either an HSI type display or via HITS information on the PFD
d) send those ARINC commands to the VSGV AP which in turn causes it to track the inbound course and follow the vertical guidance of the ILS

That above is how they do not only ILS functions, but how they track LOC and GPS stuff as well.

So to specifically answer your question, NO, the VSGV AP can't take an ILS signal as input and follow it, but if you have an EFIS system that knows how to process the ILS commands, generate the eqivalent AP commands, then you can accomodate the feature you are looking for.

Hope this helps,

tc1234c
08-11-2007, 07:51 AM
I have SL30, GRT EFIS, and TT DF II VSGV. AP is driven by EFIS. It does ILS/GS and synthetic approach from GRT.

WiseGuy
08-11-2007, 01:37 PM
What about using a GNC 430? Would that drive the autopilot?

aadamson
08-11-2007, 03:30 PM
What about using a GNC 430? Would that drive the autopilot?

Would drive it for Horizontal commands via ARINC, but won't drive it for vertical I don't believe (someone with specific information, please chime in). (NOTE, it might be that a "W" 430 would, but I suspect only for GPS approaches and not for ILS type).

The airplane that I'm flying has a 430 and a CDI, but in order for it to do a coupled ILS, it had to have the DFC-250 (the version prior to the sorcerer) in order to do vertical off the Glide Slope. Again, there are no provisions in the hookups to take the "up/down, left/right" low voltage indications that normally drive a CDI and put them into the VS, VSG, or VSGV. Any of those mentioned require some sort of software intervention via the EFIS - Chelton, GRT are two that I know perform as expected... There are others I'm sure as well, just not familiar with.

SteinAir
08-11-2007, 08:33 PM
Alan is right. The Digiflight II VSGV will drive the UP/Down as well as the Left/Right from a GNS430/530 "W" during a WAAS GPS approach only. NO ILS analog signals without moving up to the AP-100 or Sorcerer.

Cheers,
Stein.