G5 HSI and KAP 140

[Mike Bushard Jr]

Hello POA,

I got a call from the avionics shop doing our install yesterday, they are basically done with our panel upgrade. Pull the KLN 94, KX 155a #2, KR 87 ADF, and KT 76c. Installed GNS 530W (We have other places with GNS 530w's and we wanted to keep things the same), G5 HSI W/ GAD29b, GTX 345.

The shop says the G5 HSI doesn't output the right information/flags for the autopilot to track a VOR. I had not saw or heard of this limitation. I called Garmin support, they don't seem to know anything about it either. I emailed the shop and asked that they check with their Garmin rep to verify. The plane had a KI 209 and a DG before with the switcher/annunciation panel. It's/was a 172R Nav II Panel.

Has this been a known thing and I just missed it? Anybody flying with a similar setup that can speak first hand?

It's probably not a huge deal, but it's bugging me...

Thank you for the help, let me mow if I missed some critical info to help answer this.

 

[Mike Bushard Jr]

Since panel pictures are fun to look at, here are the before pictures.

 

[NavAir]

If your avionics shop works on B/K autopilots, they should have a laptop/connector to interface with your KAP-140. You are able to read many parameters, including specifically:

Heading Datum and Course Datum from the HSI
Nav Deviation and GS Deviation, Nav Valid, DG Valid, and GS Valid from the Nav receiver

The KAP-140 Flightline Maintenance Manual gives the valid ranges for these parameters. They can check what is being output to your autopilot. I suspect there are setup menus for your G5 and GNS 530 that will allow you to set up the data correctly.

Good luck!

Steve

 

[bnt83]

My airplane had a GI106A and GTN prior to the G5/GAD29B installation. The autopilot's "Nav 1" input was wired to the CDI Left/Right wires.

Those wires still exist and are live post G5/GAD29B install, allowing the autopilot to track the VOR when selected, even though the CDI unit is gone and all the information it used to display is on the G5.

I can't imagine a KAP140 would be any different but it's obvious they started from scratch and didn't hook the 530w CDI output to anything and assumed the G5 system would do everything.

 

[Mike Bushard Jr]

Thank you for the input. I’m not sure what they did I guess. We had a KLN 94 and dual KX155A’s before with the Ki-209 and a DG.

They test flew it Friday based on my FlightAware alerts, but I didn’t hear how it went. Hopefully all goes well. I’m not going to give up until I have a clear answer.