n468ac

n468ac

Well Known Member
Need help with our 430W trying to figure it out.

Question:

When flying the ILS with the 430W in VOCLOC mode it sees the ILS guidance and displays it on our GRT HX.

BUT ? when coupled to our TruTrak [FONT='Arial','sans-serif']DigiFlight II VSGV[/FONT], the autopilot fly?s to the final fix and the glide slope ? then the 430W quits sending to the autopilot and it (the autopilot) goes back to manual mode.

Is this normal?? Do you have to hand fly the final with an ILS?


When we fly a GPS approach the TruTrak will follow the 430W all the way to the runway without any problem.
 
n468ac said:
Is this normal?? Do you have to hand fly the final with an ILS?
Click to expand...

I remember reading somewhere that the 430W will stop sending out GPSS steering commands when it passes the FAF on a VOR/LOC/ILS approach. It's a bummer, but I think it said it was something to do with TSO certification, so what can you do.

mcb
 
From what I know Matt is correct. I think this was done for some certification and/or functional reason. You should however be able to run the analog ILS signals through your GRT which will continue to digest and regurgitate the signals as an ARINC....or get a Sorcerer (which watches both ARINC and analog), or fly a GPS approach which is as well know quite a lot more accurate than an ILS when available.

My 2 cents as usual.

Cheers,
Stein
 
My Digitrak II VSGV flies the ILS beautifully. However to do that it has to be controlled thru the GRT EFIS. The ILS approach has to be armed in the GRT and the ILS frequency selected on the 430W. Your GRT has to be equipped with an ARINC module. On the auto pilot you have to select the GPSS mode for lateral steering and the GPSV mode for the vertical part. Also make sure you have NAV selected for AP steering and not Heading. This configuration will also fly GPS WAAS approaches including vertical steering. Mine even flies proceedure turns and holds but only after I used the latest version of GRT's software and hooked up a 3rd AIRINC out put from the 430W.

Martin Sutter
building and flying RV's since 1988
 
thanks everyone.


I was hoping it wasn't a bad 430W or we missed wired something.​
 
Martin Sutter said:
The ILS approach has to be armed in the GRT and the ILS frequency selected on the 430W. Your GRT has to be equipped with an ARINC module. On the auto pilot you have to select the GPSS mode for lateral steering and the GPSV mode for the vertical part. Also make sure you have NAV selected for AP steering and not Heading. This configuration will also fly GPS WAAS approaches including vertical steering. Mine even flies proceedure turns and holds but only after I used the latest version of GRT's software and hooked up a 3rd AIRINC out put from the 430W.

Martin Sutter
building and flying RV's since 1988
Click to expand...
What about a missed approach? Can that be triggered from the GRT or do you need to switch AP source back to the 430?
 
The auto pilot must remain under the control of the GRT to do the missed approach. Hit "suspend " on the 430W and "missed" on the GRT after passing the missed approach point. AP NAV mode should be on GPS on the GRT as the missed course is GPS driven.

Martin Sutter
building and flying RV's since 1988
 
I have a separate switch that selects input from the GRT EFIS or the 430W. If I want the TruTrak AP to fly the full approach with course reversals etc. as directed by the 430W, I must have the switch on the GRT side. With the newest software, I must have selected GNAV mode and not arm the ILS approach until just before I am established on final. This is also the time that the 430W automatically switches from GPS mode to VLOC if the approach has been loaded in the 430W. I also switch to LNAV mode on the GRT EFIS at that time. If I do my part, the TT will send me right down the slope. This also works with a VNAV approach.

I have found that if I want to fly an approach with vectors to final on a VNAV (WASS) approach, I must wait until established before arming the approach on the GRT EFIS. I had a time figuring that out! I had always wanted to get as many buttons pushed en-route before I got into the busy time and had been arming either the ILS or the GPS approach early. I had a few controllers really upset with me while I was trying to figure that one out.

I also found that if I had a LOC frequencyloaded in the 430W nav radio, I would not get a "glide slope" indication on the GRT EFIS on a VNAV approach. It works fine if a VOR frequency is loaded into the 430W.

One last little thing I have found on a ILS/LOC approach is that to select a tract on the GRT I must have the HSI displayed for the right hand knob to work.

The GRT is a great unit but some of the things that I found are required to fly a coupled approach using the GNS 430W, the TruTrak and the GRT EFIS are not documented!
 
I know Cleve has a 430 and I have a 480 so there may or may not be differences in the GPS settings but here are the steps from my IAP checklists that have been tested and work well (using V32). I also leave my LAT A/P in GNAV unless being vectored.

In the 480 and I believe the 430 also does this, when the ILS frequency is set as the primary frequency, it will automatically change the CDI from GPS to LOC/ILS when it gets close or captures the LOC. At this point is when you ARM the ILS. Prior to that it is grayed out.

ILS Approach
? ILS Frequency ? SET
? Cross VOR Radial - SET
? NAV Mode ? GPS
? LAT A/P ? GNAV
? DA & Missed Altitudes ? SET
? Timer - SET
? ILS ? ARM After CDI Changes to ILS
? Timer On - @ FAF

For VTF
? LAT A/P ? HDG
? USE HEADING BUG TO STEER AIRCRAFT (left knob)
? ILS ? ARM After CDI Changes to ILS

MISSED APPROACH
? LAT A/P ? GNAV
? NAV Mode ? GPS
 
Yes Mike, I have version 32 of GRT software and the third ARINC pair connected. Works great!

Martin Sutter
building and flying RV's since 1988
 
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